1.1: Introduction
If you were to sit with ten directors and ask them that question you would receive ten different answers. That is because each director develops a system based on their experiences crafting and producing plays. Since every individual is different and each artist that a director is forced to work with has different ways of working and communicating, then it is obvious that each director would develop a system/perspective/ideology that would respond to those experiences and allow them to be successful. While those experiences would vary in approach and perspective there are several common factors that will be found in all approaches.
A Director is a leader. The director is the glue holding together the production and is the central hub of communication between all of the elements that make up a production. A director does not always need a plan (although it helps) nor do they need to be the most knowledgeable person in the space. However, they must be an effective communicator and have skills in developing trusting relationships with those they work with. A Director needs to be able to have an idea of what they want, but be open to letting the artists you are working with help shape that idea. As a director you are going to work with difficult people, artists are often difficult, but all people want to be treated with respect and dignity and feel like their ideas have value. If you wish to be a director you will need to be good at dealing with different personality types, you will need to be good at listening, and you will have to get good at both negotiating and compromise.
A Director is patient yet demanding. I realize that statement seems like a controdiction but it is not. A Director demands each participant brings their best work, creates a game plan for success, and is constantly working to improve. Yet, as a director you will quickly find that all of the plans you have made are not possible, or that an actor is late, a designer is behind, or those supplies you desperately needed will not come in time for the show. It is at these moments where you must be patient. You must learn to deal with failure in a positive way. Obstacles force us to be creative and live in the moment and creativity is maximized when living in the moment. Remember when you are in stressful situations that you can turn any loss into a win with the right perspective. Furthermore, you do not need to solve every problem by yourself. You have a collection of brilliant minds by your side that also want your project to be successful. Your creative team can help solve these problems.
A director must believe in the project. I cannot stress this enough. Ernest Hemmingway said, “Writing is easy, you just sit at the typewriter and bleed.” Directing a show is no different. As a director you are taking a part of yourself, your dreams, your perspective, and in a way your soul and planting it into the show. The show has to be important to you, otherwise why would you spend so much time, effort, blood, sweat, and tears into it? You will be investing six weeks or more into this project. You will also be asking others to invest six or more weeks of their lives in this project and support your vision. You have to believe that the messages held in the show will inspire both your audience and those in the show as well. When you believe in what you are doing, you gain support, determination, and provide the building blocks of success. Most of the things we have in our lives are only held together and are only possible as a result of belief.
Finally a director should know (though they sometimes do not) dramatic structure and basic staging principals. This is one of the major purposes of creating the book. Technique can be taught and you have to get practice in actually directing and staging if you are ever going to be good.


14.1.3: Urbanization and the Development of Cities
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The Earliest Cities
Early cities arose in a number of regions, and are thought to have developed for reasons of agricultural productivity and economic scale.
Learning Objectives
Summarize the various beginnings of cities, from centers of agriculture to areas of protection, and the factors they need to be successful
Key Points
- The very first cities were founded in Mesopotamia after the Neolithic Revolution, around 7500 BCE.
- Agriculture is believed to be a pre-requisite for cities, which help preserve surplus production and create economies of scale.
- Cities reduced transport costs for goods, people, and ideas by bringing them all together in one spot.
Key Terms
- Old World : The known world before the discovery of the Americas.
- Neolithic Revolution : The Neolithic Revolution or Neolithic Demographic Transition, sometimes called the Agricultural Revolution, was the world’s first historically verifiable revolution in agriculture.
- urbanism : the study of cities, their geographic, economic, political, social, and cultural environment
Early cities developed in a number of regions, from Mesopotamia to Asia to the Americas. The very first cities were founded in Mesopotamia after the Neolithic Revolution, around 7500 BCE. Mesopotamian cities included Eridu, Uruk, and Ur. Early cities also arose in the Indus Valley and ancient China. Among the early Old World cities, one of the largest was Mohenjo-daro, located in the Indus Valley (present-day Pakistan); it existed from about 2600 BCE, and had a population of 50,000 or more. In the ancient Americas, the earliest cities were built in the Andes and Mesoamerica, and flourished between the 30 th century BCE and the 18 th century BCE.
Ancient cities were notable for their geographical diversity, as well as their diversity in form and function. Theories that attempt to explain ancient urbanism by a single factor, such as economic benefit, fail to capture the range of variation documented by archaeologists. Excavations at early urban sites show that some cities were sparsely populated political capitals, others were trade centers, and still other cities had a primarily religious focus. Some cities had large dense populations, whereas others carried out urban activities in the realms of politics or religion without having large associated populations. Some ancient cities grew to be powerful capital cities and centers of commerce and industry, situated at the centers of growing ancient empires. Examples include Alexandria and Antioch of the Hellenistic civilization, Carthage, and ancient Rome and its eastern successor, Constantinople (later Istanbul).
The Formation of Cities
Why did cities form in the first place? There is insufficient evidence to assert what conditions gave rise to the first cities, but some theorists have speculated on what they consider pre-conditions and basic mechanisms that could explain the rise of cities. Agriculture is believed to be a pre-requisite for cities, which help preserve surplus production and create economies of scale. The conventional view holds that cities first formed after the Neolithic Revolution, with the spread of agriculture. The advent of farming encouraged hunter-gatherers to abandon nomadic lifestyles and settle near others who lived by agricultural production. Agriculture yielded more food, which made denser human populations possible, thereby supporting city development. Farming led to dense, settled populations, and food surpluses that required storage and could facilitate trade. These conditions seem to be important prerequisites for city life. Many theorists hypothesize that agriculture preceded the development of cities and led to their growth.
A good environment and strong social organization are two necessities for the formation of a successful city. A good environment includes clean water and a favorable climate for growing crops and agriculture. A strong sense of social organization helps a newly formed city work together in times of need, and it allows people to develop various functions to assist in the future development of the city (for example, farmer or merchant). Without these two common features, as well as advanced agricultural technology, a newly formed city is not likely to succeed.
Cities may have held other advantages, too. For example, cities reduced transport costs for goods, people, and ideas by bringing them all together in one spot. By reducing these transaction costs, cities contributed to worker productivity. Finally, cities likely performed the essential function of providing protection for people and the valuable things they were beginning to accumulate. Some theorists hypothesize that people may have come together to form cities as a form of protection against marauding barbarian armies.
Preindustrial Cities
Preindustrial cities had important political and economic functions and evolved to become well-defined political units.
Learning Objectives
Examine the growth of preindustrial cities as political units, as well as how trade routes allowed certain cities to expand and grow
Key Points
- Preindustrial cities were political units, like today’s states. They offered freedom from rural obligations to lord and community.
- In the early modern era, larger capital cities benefited from new trade routes and grew even larger.
- While the city-states, or poleis, of the Mediterranean and Baltic Sea languished from the 16th century, Europe’s larger capitals benefited from the growth of commerce following the emergence of an Atlantic trade.
Key Terms
- lord : A titled nobleman or aristocrat
- rural obligations : For people during the medieval era, cities offered a newfound freedom from rural obligations. City residence brought freedom from customary rural obligations to lord and community.
- Preindustrial cities : While ancient cities may have arisen organically as trading centers, preindustrial cities evolved to become well defined political units.
Cities as Political Centers
While ancient cities may have arisen organically as trading centers, preindustrial cities evolved to become well defined political units, like today’s states. During the European Middle Ages, a town was as much a political entity as a collection of houses. However, particular political forms varied. In continental Europe, some cities had their own legislatures. In the Holy Roman Empire, some cities had no other lord than the emperor. In Italy, medieval communes had a state-like power. In exceptional cases like Venice, Genoa, or Lübeck, cities themselves became powerful states, sometimes taking surrounding areas under their control or establishing extensive maritime empires. Similar phenomena existed elsewhere, as in the case of Sakai, which enjoyed a considerable autonomy in late medieval Japan.
For people during the medieval era, cities offered a newfound freedom from rural obligations. City residence brought freedom from customary rural obligations to lord and community (hence the German saying, “ Stadtluft macht frei ,” which means “City air makes you free”). Often, cities were governed by their own laws, separate from the rule of lords of the surrounding area.
Trade Routes
Not all cities grew to become major urban centers. Those that did often benefited from trade routes—in the early modern era, larger capital cities benefited from new trade routes and grew even larger. While the city-states, or poleis, of the Mediterranean and Baltic Sea languished from the 16 th century, Europe’s larger capitals benefited from the growth of commerce following the emergence of an Atlantic trade. By the early 19 th century, London had become the largest city in the world with a population of over a million, while Paris rivaled the well-developed regional capital cities of Baghdad, Beijing, Istanbul, and Kyoto. But most towns remained far smaller places—in 1500 only about two dozen places in the world contained more than 100,000 inhabitants. As late as 1700 there were fewer than 40, a figure which would rise thereafter to 300 in 1900. A small city of the early modern period might have contained as few as 10,000 inhabitants.
Industrial Cities
During the industrial era, cities grew rapidly and became centers of population growth and production.
Learning Objectives
Discuss the problems urbanization created for newly formed cities
Key Points
- Rapid growth brought urban problems, and industrial-era cities were rife with dangers to health and safety.
- Poor sanitation and communicable diseases were among the greatest causes of death among urban working class populations.
- In the 19th century, better sanitation led to improved health conditions.
Key Terms
- industrial cities : Rapid growth brought urban problems, and industrial-era cities were rife with dangers to health and safety. Quickly expanding industrial cities could be quite deadly, full of contaminated water and air, and communicable diseases.
- industrial era : During the industrial era, cities grew rapidly and became centers of population and production.
During the industrial era, cities grew rapidly and became centers of population and production. The growth of modern industry from the late 18 th century onward led to massive urbanization and the rise of new, great cities, first in Europe, and then in other regions, as new opportunities brought huge numbers of migrants from rural communities into urban areas. In 1800, only 3% of the world’s population lived in cities. Since the industrial era, that figure, as of the beginning of the 21 st century, has risen to nearly 50%. The United States provides a good example of how this process unfolded; from 1860 to 1910, the invention of railroads reduced transportation costs and large manufacturing centers began to emerge in the United States, allowing migration from rural to urban areas.
Rapid growth brought urban problems, and industrial-era cities were rife with dangers to health and safety. Rapidly expanding industrial cities could be quite deadly, and were often full of contaminated water and air, and communicable diseases. Living conditions during the Industrial Revolution varied from the splendor of the homes of the wealthy to the squalor of the workers. Poor people lived in very small houses in cramped streets. These homes often shared toilet facilities, had open sewers, and were prone to epidemics exacerbated by persistent dampness. Disease often spread through contaminated water supplies.
In the 19 th century, health conditions improved with better sanitation, but urban people, especially small children, continued to die from diseases spreading through the cramped living conditions. Tuberculosis (spread in congested dwellings), lung diseases from mines, cholera from polluted water, and typhoid were all common. The greatest killer in the cities was tuberculosis (TB). Archival health records show that as many as 40% of working class deaths in cities were caused by tuberculosis.
The Structure of Cities
Urban structure is the arrangement of land use, explained using different models.
Learning Objectives
Analyze, using human ecology theory, the similarities and differences between the various urban structure models, such as grid model, sectoral model and concentric ring model, among others
Key Points
- In the grid model of cities, land is divided by streets that run at right angles to each other, forming a grid. This model promotes development.
- The concentric ring model describes the city as an ecosystem in which residents sort themselves into a series of rings based on class and occupation. This model’s general applicability has been challenged.
- Urban structure can also describe the location of the central business district, industrial parks, or urban open spaces.
- The sectoral model says the city develops in wedge-shaped sectors instead of rings: certain areas of a city are more attractive for various activities, which flourish and expand outward in a wedge.
- The multiple nuclei model assumes that car ownership granted people more mobility and led the the development of specialized regional centers within cities.
- The irregular pattern model was developed to better explain urban structure in the Third World. It attempts to model the lack of planning or construction found in many rapidly built Third World cities.
Key Terms
- central business district : The central area of a city in which a concentration of certain retail and business activities takes place, especially in older cities with rail transportation.
- urban open space : In land use planning, urban open space is open space areas for parks, green spaces, and other open areas.
- Human Ecology : Human ecology described the city as analogous to an ecosystem, with natural processes of adaptation and assimilation.
Urban Structure Models
Grid
In grid models, land is divided by streets intersect at right angles, forming a grid. Grid plans are more common in North American cities than in Europe, where older cities tend to be build on streets that radiate out from a central square or structure of cultural significance. Grid plans facilitate development because developers can subdivide and auction off large parcels of land. The geometry yields regular lots that maximize use and minimize boundary disputes. However, grids can be dangerous because long, straight roads allow faster automobile traffic. In the 1960s, urban planners moved away from grids and began planning suburban developments with dead ends and cul-de-sacs.
Concentric Ring Model
The concentric ring model was postulated in 1924 by sociologist Ernest Burgess, based on his observations of Chicago. It draws on human ecology theories, which compared the city to an ecosystem, with processes of adaptation and assimilation. Urban residents naturally sort themselves into appropriate rings, or ecological niches, depending on class and cultural assimilation. The innermost ring represents the central business district (CBD), called Zone A.. It is surrounded by a zone of transition (B), which contains industry and poorer-quality housing. The third ring (C) contains housing for the working-class—the zone of independent workers’ homes. The fourth ring (D) has newer and larger houses occupied by the middle-class. The outermost ring (E), or commuter’s zone, is residential suburbs.
This model’s general applicability has been challenged. It describes an American geography in which the inner city is poor while suburbs are wealthy—elsewhere, the converse is the norm. In new, western U.S. cities such as Los Angeles, advances in transportation and communication have blurred these “zones. ” Further, the model fails to account for topographical and physical features of the landscape. Even in Chicago, the concentric rings were semi-circles, interrupted by Lake Michigan.
Sectoral
In 1939, the economist Homer Hoyt adapted the concentric ring model by proposing that cities develop in wedge-shaped sectors instead of rings. Certain areas of a city are more attractive for various activities, whether by chance or geographic/environmental reasons. As these activities flourish and expand outward, they form wedges, becoming city sectors. Like the concentric ring model, Hoyt’s sectoral model has been criticized for ignoring physical features and new transportation patterns that restrict or direct growth.
Multiple Nuclei
The multiple nuclei model was developed in 1945 to explain city formation after the spread of the automobile. People have greater movement due to increased car ownership, allowing for the specialization of regional centers. A city contains more than one center around which activities revolve. Some activities are attracted to particular nodes while others try to avoid them. For example, a university node may attract well-educated residents, pizzerias, and bookstores, whereas an airport may attract hotels and warehouses. Incompatible activities will avoid clustering in the same area.
Irregular Pattern
The irregular pattern model was developed to explain urban structure in the Third World. It attempts to model the lack of planning found in many rapidly built Third World cities. This model includes blocks with no fixed order; urban structure is not related to an urban center or CBD.
Alternate Uses of “Urban Structure”
Urban structure can also refer to urban spatial structure; the arrangement of public and private space in cities and the degree of connectivity and accessibility. In this context, urban structure is concerned with the arrangement of the CBD, industrial and residential areas, and open space.
A city’s central business district (CBD), or downtown, is the commercial and often geographic heart of a city. In North America, this is referred to as “downtown” or “city center. ” The downtown area is often home to the financial district, but usually also contains entertainment and retail. CBDs usually have very small resident populations, but populations are increasing as younger professional and business workers move into city center apartments.
An industrial park is an area zoned and planned for the purpose of industrial development. They are intended to attract business by concentrating dedicated infrastructure to reduce the per-business expenses. They also set aside industrial uses from urban areas to reduce the environmental and social impact of industrial uses and to provide a distinct zone of environmental controls specific to industrial needs.
Urban open spaces provide citizens with recreational, ecological, aesthetic value. They can range from highly maintained environments to natural landscapes. Commonly open to public access, they may be privately owned. Urban open spaces offer a reprieve from the urban environment and can add ecological value, making citizens more aware of their natural surroundings and providing nature to promote biodiversity. Open spaces offer aesthetic value for citizens who enjoy nature, cultural value by providing space for concerts or art shows, and functional value—for example, by helping to control runoff and prevent flooding.
The Process of Urbanization
Urbanization is the process of a population shift from rural areas to cities, often motivated by economic factors.
Learning Objectives
Analyze the proces of urbanization and its effects on economics and the environment in society
Key Points
- Urbanization may be driven by local and global economic and social changes, and is generally a product of modernization and industrialization.
- Urbanization has economic and environmental effects. Economically, urbanization drives up prices, especially real estate, which can force original residents to move to less-desirable neighborhoods.
- Environmentally, cities cause “heat islands”, where less vegetation and open soil raise city temperatures by 2 to 10 degrees Fahrenheit.
- Recently in developed countries, sociologists have observed suburbanization and counterurbanization, or movement away from cities, which may be driven by transportation infrastructure, or social factors like racism.
Key Terms
- suburbanization : A term used to describe the growth of areas on the fringes of major cities; one of the many causes of the increase in urban sprawl.
- rural flight : A term used to describe the migratory patterns of peoples from rural areas into urban areas.
- urbanization : The physical growth of urban areas as a result of rural migration and even suburban concentration into cities.
- counterurbanization : A demographic and social process whereby people move from urban areas to rural areas.
- gentrification : A shift in an urban community toward wealthier residents and/or businesses and increasing property values; often resulting in poorer residents being displaced by wealthier newcomers.
Urbanization and rural flight
Urbanization is the process of a population shift from rural areas to cities. During the last century, global populations have urbanized rapidly:
- 13% of people lived in urban environments in the year 1900
- 29% of people lived in urban environments in the year 1950
One projection suggests that, by 2030, the proportion of people living in cities may reach 60%.
Urbanization tends to correlate positively with industrialization. With the promise of greater employment opportunities that come from industrialization, people from rural areas will go to cities in pursuit of greater economic rewards.
Another term for urbanization is “rural flight. ” In modern times, this flight often occurs in a region following the industrialization of agriculture—when fewer people are needed to bring the same amount of agricultural output to market—and related agricultural services and industries are consolidated. These factors negatively affect the economy of small- and middle-sized farms and strongly reduce the size of the rural labor market. Rural flight is exacerbated when the population decline leads to the loss of rural services (such as business enterprises and schools), which leads to greater loss of population as people leave to seek those features.
As more and more people leave villages and farms to live in cities, urban growth results. The rapid growth of cities like Chicago in the late nineteenth century and Mumbai a century later can be attributed largely to rural-urban migration. This kind of growth is especially commonplace in developing countries.
Urbanization occurs naturally from individual and corporate efforts to reduce time and expense in commuting, while improving opportunities for jobs, education, housing, entertainment, and transportation. Living in cities permits individuals and families to take advantage of the opportunities of proximity, diversity, and marketplace competition. Due to their high populations, urban areas can also have more diverse social communities than rural areas, allowing others to find people like them.
A link to the YouTube element can be found in Contributors & Attributions section.
Megacities Reflect Growing Urbanization Trend – YouTube : In the developing world, huge cities with sprawling slums have developed as agriculture and rural occupations have been supplanted by mechanized industries.
Economic and Environmental Effects of Urbanization
Urbanization has significant economic and environmental effects on cities and surrounding areas. As city populations grow, they increase the demand for goods and services of all kinds, pushing up prices of these goods and services, as well as the price of land. As land prices rise, the local working class may be priced out of the real estate market and pushed into less desirable neighborhoods – a process known as gentrification.
Growing cities also alter the environment. For example, urbanization can create urban “heat islands,” which are formed when industrial and urban areas replace and reduce the amount of land covered by vegetation or open soil. In rural areas, the ground helps regulate temperatures by using a large part of the incoming solar energy to evaporate water in vegetation and soil. This evaporation, in turn, has a cooling effect. However in cities, where less vegetation and exposed soil exists, the majority of the sun’s energy is absorbed by urban structures and asphalt. During the day, cities experience higher surface temperatures because urban surfaces produce less evaporative cooling. Additional city heat is given off by vehicles and factories, as well as industrial and domestic heating and cooling units. Together, these effects can raise city temperatures by 2 to 10 degrees Fahrenheit (or 1 to 6 degrees Celsius).
Suburbanization and Counterurbanization
Recently in developed countries, sociologists have observed suburbanization and counterurbanization, or movement away from cities. These patterns may be driven by transportation infrastructure, or social factors like racism. In developed countries, people are able to move out of cities while still maintaining many of the advantages of city life (for instance, improved communications and means of transportation). In fact, counterurbanization appears most common among the middle and upper classes who can afford to buy their own homes.
Race also plays a role in American suburbanization. During World War I, the massive migration of African Americans from the South resulted in an even greater residential shift toward suburban areas. The cities became seen as dangerous, crime-infested areas, while the suburbs were seen as safe places to live and raise a family, leading to a social trend known in some parts of the world as “white flight. ” Some social scientists suggest that the historical processes of suburbanization and decentralization are instances of white privilege that have contributed to contemporary patterns of environmental racism.
In the United States, suburbanization began in earnest after World War II, when soldiers returned from war and received generous government support to finance new homes. Suburbs, which are residential areas on the outskirts of a city, were less crowded and had a lower cost of living than cities. Suburbs grew dramatically in the 1950s when the U.S. interstate highway system was built, and automobiles became affordable for middle class families. Around 1990, another trend emerged known as counterurbanization, or “exurbanization”. The wealthiest individuals began living in nice housing far in rural areas (as opposed to forms).
Suburbanization may be a new urban form.Rather than densely populated centers, cities may become more spread out, composed of many interconnected smaller towns. Interestingly, the modern U.S. experience has gone from a largely rural country, to a highly urban country, to a country with significant suburban populations.
U.S. Urban Patterns
The U.S. Census Bureau classifies areas as urban or rural based on population size and density.
Learning Objectives
Discuss the different ways governments and society define the term “urban”
Key Points
- Different agencies and individuals define urban in different ways, but the U.S. Census Bureau ‘s definitions are considered standard.
- The U.S. Census Bureau defines “urban areas” as areas with a population density of at least 1,000 people per square mile and at least 2,500 total people.
- As of December, 2010, about 82% of the population of the United States lived within the boundaries of urbanized area.
Key Terms
- population density : The average number of people who live on each square mile (or kilometer) of land.
Different international, national, and local agencies may define “urban” in various ways. For example, city governments often use political boundaries to delineate what counts as a city. Other definitions may consider total population size or population density. Different definitions may also set various thresholds, so that in some cases, a town of just 2,500 may count as an urban city, whereas in other contexts, a city may be defined as having at least 50,000 people. Other agencies may define “urban” based on land use: places count as urban if they are built up with residential neighborhoods, industrial sites, railroad yards, cemeteries, airports, golf courses, and similar areas. Using this sort of definition, in 1997, the U.S. Department of Agriculture tallied over 98,000,000 acres of “urban” land.
In spite of these competing definitions, in the United States “urban” is officially defined following guidelines set by the U.S. Census Bureau. The Census Bureau defines “urban areas” as areas with a population density of at least 1,000 people per square mile and at least 2,500 total people. Urban areas are delineated without regard to political boundaries. Because this definition does not consider political boundaries, it is often used as a more accurate gauge of the size of a city than the number of people who live within the city limits. Often, these two numbers are not the same. For example, the city of Greenville, South Carolina has a city population under 60,000 and an urbanized area population of over 300,000, while Greensboro, North Carolina has a city population over 200,000 and an urbanized area population of around 270,000. That means that Greenville is actually “larger” for some intents and purposes, but not for others, such as taxation, local elections, etc.
As of December, 2010, about 82% of the population of the United States lived within the boundaries of urbanized area. Combined, these areas occupy about 2% of the land area of the United States. The majority of urbanized area residents are suburbanites; core central city residents make up about 30% of the urbanized area population (about 60 million out of 210 million). In the United States, the largest urban area is New York City, with over 8 million people within the city limits and over 19 million in the urban area. The next five largest urban areas in the United States are Los Angeles, Chicago, Washington, D.C., Philadelphia, and Boston.
The Rural Rebound
During the 1970s and again in the 1990s, the rural population rebounded in what appeared to be a reversal of urbanization.
Learning Objectives
Explain the rural rebound and how it contributes to the suburbanization of society
Key Points
- Much of the “rural” rebound was driven by suburbanization, which is the movement of people from cities to surrounding suburbs, ex-urbs, or edge cities.
- Suburbanization may be driven by white flight.
- Counterurbanization refers, broadly, to movement away from the city, which may include urban-to-rural migration and suburbanization.
- Counterurbanization has created shrinking cities and attempts to better control urban growth.
Key Terms
- white flight : The large-scale migration of whites of various European ancestries, from racially mixed urban regions to more racially homogeneous suburban areas.
- ex-urbs : The expression exurb (for “extra-urban”) was coined by Auguste Comte Spectorsky in his 1955 book The Exurbanites to describe the ring of prosperous communities beyond the suburbs that are commuter towns for an urban area.
- counterurbanization : Counterurbanisation is a demographic and social process whereby people move from urban areas to rural areas.
The rural rebound refers to the movement away from cities to rural and suburban areas. Urbanization tends to occur along with modernization, yet in the most developed countries many cities are now beginning to lose population. In the United States in the 1970s, demographers observed that the rural population was actually growing faster than urban populations, a phenomenon they labeled the “rural rebound. ” This trend reversed in the 1980s, due in part to a recession that hit farmers particularly hard. But again in the 1990s, rural populations appeared to be gaining at the expense of cities. Indeed, in the last 50 years, about 370 cities worldwide with more than 100,000 residents have undergone population losses of more than 10%, and more than 25% of the depopulating cities are in the United States.
Rather than moving to rural areas, most participants in the so-called the rural rebound migrated into new, rapidly growing suburbs. The rural rebound, then, may be more evidence of the importance of suburbanization as a new urban form in the most developed countries.
Suburbanization
Suburbanization is a general term that refers to the movement of people from cities to surrounding areas. However, the suburbanization that took place after 1970 was different from the suburbanization that had occurred earlier, after World War II. In this more recent wave of suburbanization, people moved beyond the nearby suburbs to farther-away towns. Sociologists have invented several new categories to describe these new types of suburban towns; two of the most notable are ex-urbs and edge cities.
The expression exurb (for “extra-urban”) refers to a ring of prosperous communities beyond a city’s suburbs. Often, these communities are commuter towns or bedroom communities. Commuter towns are primarily residential; most of the residents commute to jobs in the city. They are sometimes called bedroom communities because residents spend their days away in the cities and only come home to sleep. In general, commuter towns have little commercial or industrial activity of their own, though they may contain some retail centers to serve the daily needs of residents. Although most exurbs are commuter towns, most commuter towns are not exurban.
Exurbs vary in wealth and education level. In the United States, exurban areas typically have much higher college education levels than closer-in suburbs, though this is not necessarily the case in other countries. They typically have average incomes much higher than nearby rural counties, reflecting the urban wages of their residents. Although some exurbs are quite wealthy even compared to nearer suburbs or the city itself, others have higher poverty levels than suburbs nearer the city. This may happen especially where commuter towns form because workers in a region cannot afford to live where they work and must seek residency in another town with a lower cost of living. For example, during the “dot com” bubble of the late twentieth century, housing prices in California cities skyrocketed, spawning exurban growth in adjacent counties.
White Flight
Sociologists have posited many explanations for counterurbanization, but one of the most debated is whether suburbanization is driven by white flight. The term white flight was coined in the mid-twentieth century to describe suburbanization and the large-scale migration of whites of various European ancestries, from racially mixed urban regions to more racially homogeneous suburban regions. During the first half of the twentieth century, discriminatory housing policies often prevented blacks from moving to suburbs; banks and federal policy made it difficult for blacks to get the mortgages they needed to buy houses, and communities used restrictive housing covenants to exclude minorities.
White flight during this period contributed to urban decay, a process whereby a city, or part of a city, falls into disrepair and decrepitude. Symptoms of urban decay include depopulation, abandoned buildings, high unemployment, crime, and a desolate, inhospitable landscape. White flight contributed to the draining of cities’ tax bases when middle-class people left, exacerbating urban decay caused in part by the loss of industrial and manufacturing jobs as they moved into rural areas or overseas where labor was cheaper.
More recently, the concept has been extended to newer forms of suburbanization, including migration from urban to rural areas and to exurbs. In a similar vein, some demographers have described the rural rebound, and the newest waves of suburbanization, as a form of ethnic balkanization, in which different ethnic groups (not only whites) sort themselves into racially homogeneous communities. These phenomena, however, are not so clearly driven by the restrictive policies, laws, and practices that drove the white flight of the first half of the century.
Models of Urban Growth
Models of urban growth try to balance the advantages and disadvantages of cities’ large sizes.
Learning Objectives
Summarize the various theories of urban growth and the implications each theory has for today’s society
Key Points
- The growth machine theory of urban growth says urban growth is driven by a coalition of interest groups who all benefit from continuous growth and expansion. Thus, the growth of cities is a social phenomenon.
- Urban sprawl results when cities grow uncontrolled, expanding into rural land and making walking, public transit, or bicycling impractical.
- Critics of urban life often focus on urban decay, which may be self-perpetuating, according to the broken windows theory.
- Urban renewal attempts to counter urban decay and restore growth.
- The New Urbanism and smart growth movements both challenge the value of urban growth and expansion, and they try to improve urban life by keeping it on a human scale.
Key Terms
- smart growth : Smart growth programs draw urban growth boundaries to keep urban development dense and compact.
- urban renewal : Urban renewal refers to programs of land redevelopment in areas of moderate- to high-density urban land use.
- New Urbanism : New Urbanism is an urban design movement that promotes walkable neighborhoods that contain a range of housing and job types.
Cities are dynamic places—they grow, shrink, and change. Sociologists have developed different theories for thinking about how urban populations change.
Growth Machine Theory
The growth machine theory of urban growth says urban growth is driven by a coalition of interest groups who all benefit from continuous growth and expansion. First articulated by Molotch in 1976, growth machine theory took the dominant convention of studying urban land use and turned it on its head.
The field of urban sociology had been dominated by the idea that cities were basically containers for human action, in which actors competed among themselves for the most strategic parcels of land, and the real estate market reflected the state of that competition. Growth machine theory reversed the course of urban theory by pointing out that land parcels were not empty fields awaiting human action, but were associated with specific interests—commercial, sentimental, and psychological. In other words, city residents were not simply competing for parcels of land; they were also trying to fulfill their particular interests and achieve specific goals. In particular, cities are shaped by the real estate interests of people whose properties gain value when cities grow. These actors make up what Molotch termed “the local growth machine. ”
Urban Sprawl
Whether explained by older theories of natural processes or by growth machine theory, the fact of urban growth is undeniable: throughout the twentieth century, cities have grown rapidly. In some cases, that growth has been poorly controlled, resulting in a phenomenon known as urban sprawl. Urban sprawl entails the growth of a city into low-density and auto-dependent rural land, high segregation of land use (e.g., retail sections placed far from residential areas, often in large shopping malls or retail complexes), and design features that encourage car dependency.
Urban sprawl’s segregated land use means that the places where people live, work, shop, and relax are far from one another, which usually makes walking, public transit, or bicycling impractical. As a result, residents must use an automobile. Urban sprawl tends to include low population density: single family homes on large lots instead of apartment buildings, single story or low-rise buildings instead of high-rises, extensive lawns and surface parking lots, and so on.
Critics of urban sprawl argue that it creates an inhospitable urban environment and that it encroaches on rural land, potentially driving up land prices and displacing farmers or other rural residents. Urban sprawl is also associated with negative environmental and public health effects, many of which are related to automobile dependence: increases in personal transportation costs, air pollution and reliance on fossil fuel, increases in traffic accidents, delays in emergency medical services response times, and decreases in land and water quantity and quality.
Urban Decay
Some have suggested that urban sprawl is driven by consumer preference; people prefer to live in lower density, quieter, more private communities that they perceive as safer and more relaxed than urban neighborhoods. Such preferences echo a common strain of criticism of urban life, which tends to focus on urban decay. According to these critics, urban decay is caused by the excessive density and crowding of cities, and it drives out residents, creating the conditions for urban sprawl.
BROKEN WINDOWS
An alternative theory suggests that density does not cause crime, and crime does not cause people to leave the city; when people leave, city neighborhoods are abandoned and neglected, resulting in crime and decay. This theory, known as the “broken windows theory,” argues that small indicators of neglect, such as broken windows and unkempt lawns, promote a feeling that an area is in a state of decay. Anticipating decay, people likewise fail to maintain their own properties.
RESPONSES TO DECAY
Cities have responded to urban decay and urban sprawl by launching urban renewal programs. Two specific types of urban renewal programs—New Urbanism and smart growth—attempt to make cities more pleasant and livable.
Smart growth programs draw urban growth boundaries to keep urban development dense and compact. In addition to increasing the density of cities, urban growth boundaries can protect the surrounding farmland and wild areas. Smart growth programs often incorporate transit-oriented development goals to encourage effective public transit systems and make bicyclers and pedestrians more comfortable.
New Urbanism is an urban design movement that promotes walkable neighborhoods with a range of housing options and job types. As an approach to urban planning, it encompasses principles such as traditional neighborhood design and transit-oriented development. A neighborhood designed along New Urbanist principles would have a discernible center (such as a square or a green) with a transit stop nearby. Most homes would be within a five-minute walk of the center and would provide a variety of housing options, including houses, row houses, and apartments to encourage the mixing of younger and older people, singles and families, and poor and wealthy.
Contributors and Attributions
CC licensed content, Specific attribution


7.1: Definitions - Books, Remixes, and TextMaps
There are three general classes of texts found in the LibreTexts: "Textbooks, "Remixes" and "Textmaps".
- Textbooks are texts that are original content that have integrated content into our library and are identified by "Book:" in their titles.
- Remixes are texts are created from existing OER content although often has topical or extensive editing by the remixing team to customize the text for the needs of an instructor or team of instructors. Constructing Remixes on the LibreTexts platform is facilitated by the OER Remixer tool. The title of the Remix often starts with the campus acronym (e.g., the Chemistry 110A remix at the University of California is "UCD: Chem 110A Introductory Quantum Mechanics")
- Textmaps are specialized remixes that are constructed to follow the organization of existing commercial textbooks. Textmaps facilitate adoption by faculty that are unable to switch from a commercial textbook to an OER alternative; these texts are identified by "Map:" in their titles.
Ethics and Legality of Textmaps
There was a court case in 1980 where the complaint was dismissed because, although the structure was the same, the "expression" i.e. writing was distinct. The more recent case from late 2018 says structure is part of the overall picture, and should be considered. It may be copyrightable if it were super creative, but not if it was "indispensable or standard" for the subject matter (494 F. Supp. 218). More from the case: "Similarities in chapter arrangement or structure matter less than the expressive content contain therein. Cf. Morrison v. Solomons, 494 F.Supp. 218, 225 (S.D.N.Y. 1980) (“The significant question is not whether titles of subchapters and chapters are the same but rather whether the explanation or treatment of the subject matter within them is substantially similar.”)."


2.4: Body Regions
Body Regions
Body regions are used to specifically identify a body area, such as the abdominopelvic region and the spinal region.
Abdominopelvic Region
The abdominopelvic region can be divided into nine anatomic regions to assess and precisely communicate abdominal and pelvic locations. These regions include three across the top, three across the middle, and three across the bottom. See Figure 2.4 [1] for an illustration of the abdominal region.
The center portion of the nine squares is the umbilical region. Directly above the umbilical region is the epigastric region. Directly below the umbilical region is the hypogastric region. On either side of the epigastric region are the right and left hypochondriac regions. On either side of the hypogastric region are the right and left iliac regions. For example, a nurse may document that an individual has “pain in the epigastric region after eating spicy meals.”
As illustrated in Figure 2.4, the abdominopelvic area can also be divided into four abdominal quadrants:
- Right upper quadrant (RUQ): Contains the gallbladder, the right lobe of the liver, and parts of the small and large intestines.
- Left upper quadrant (LUQ): Contains the stomach, pancreas, spleen, left lobe of the liver, and parts of the small and large intestines.
- Right lower quadrant (RLQ): Contains the appendix, right ureter, right ovary and Fallopian tube, and parts of the small and large intestines.
- Left lower quadrant (LLQ): Contains the left ureter, left ovary and Fallopian tube, and parts of the small and large intestines.
For example, a nurse may document that a patient with severe constipation “has a firm mass in the left lower quadrant.” Keep in mind that “right” and “left” refer to the patient’s right and left side, not the examiner’s view of the individual.
View the following YouTube video [2] on abdominopelvic quadrants and organs contained in each quadrant:
Vertebral Cavity Regions
The vertebral (i.e., spinal) cavity is divided into five regions. From the top, near the head, to the bottom, near the tailbone, these regions are as follows [3] :
- Cervical region: The neck region with seven cervical vertebrae from C1 to C7.
- Thoracic region: The chest region, including the thoracic vertebrae from T1 to T12. Each vertebra in this region is joined to a rib.
- Lumbar region: The region between the ribs and the hip bones, including lumbar vertebrae L1 to L5.
- Sacral region: Five sacral vertebrae, S1 to S5, that are fused to form the sacrum.
- Coccygeal region: The coccyx (i.e., tailbone) that is composed of several fused bones.
For example, a physician may document that a patient has “chronic pain in the L4 region.”
Vertebrae are further discussed in the “Anatomy of the Skeletal System” section.
- “ Abdominal_Quadrant_Regions.jpg ” by OpenStax is licensed under CC BY 3.0. Access for free at https://openstax.org/books/anatomy-and-physiology-2e/pages/1-introduction ↵
- RegisteredNurseRN. (2019, May 23). Four abdominal quadrants and nice abdominal regions - Anatomy and physiology [Video]. YouTube. All rights reserved. Reused with permission. https://www.youtube.com/watch?v=ELRzBa-eAA ↵
- This work is a derivative of StatPearls by Peabody, Black, & Das and is licensed under CC BY 4.0 ↵


14.4: Formation of the Solar System
By the end of this section, you will be able to:
- Describe the motion, chemical, and age constraints that must be met by any theory of solar system formation
- Summarize the physical and chemical changes during the solar nebula stage of solar system formation
- Explain the formation process of the terrestrial and giant planets
- Describe the main events of the further evolution of the solar system
As we have seen, the comets , asteroids , and meteorites are surviving remnants from the processes that formed the solar system. The planets, moons, and the Sun, of course, also are the products of the formation process, although the material in them has undergone a wide range of changes. We are now ready to put together the information from all these objects to discuss what is known about the origin of the solar system.
Observational Constraints
There are certain basic properties of the planetary system that any theory of its formation must explain. These may be summarized under three categories: motion constraints, chemical constraints, and age constraints. We call them constraints because they place restrictions on our theories; unless a theory can explain the observed facts, it will not survive in the competitive marketplace of ideas that characterizes the endeavor of science. Let’s take a look at these constraints one by one.
There are many regularities to the motions in the solar system. We saw that the planets all revolve around the Sun in the same direction and approximately in the plane of the Sun’s own rotation. In addition, most of the planets rotate in the same direction as they revolve, and most of the moons also move in counterclockwise orbits (when seen from the north). With the exception of the comets and other trans-neptunian objects, the motions of the system members define a disk or Frisbee shape. Nevertheless, a full theory must also be prepared to deal with the exceptions to these trends, such as the retrograde rotation (not revolution) of Venus.
In the realm of chemistry, we saw that Jupiter and Saturn have approximately the same composition—dominated by hydrogen and helium. These are the two largest planets, with sufficient gravity to hold on to any gas present when and where they formed; thus, we might expect them to be representative of the original material out of which the solar system formed. Each of the other members of the planetary system is, to some degree, lacking in the light elements. A careful examination of the composition of solid solar-system objects shows a striking progression from the metal-rich inner planets, through those made predominantly of rocky materials, out to objects with ice-dominated compositions in the outer solar system. The comets in the Oort cloud and the trans-neptunian objects in the Kuiper belt are also icy objects, whereas the asteroids represent a transitional rocky composition with abundant dark, carbon-rich material.
As we saw in Other Worlds: An Introduction to the Solar System, this general chemical pattern can be interpreted as a temperature sequence: hot near the Sun and cooler as we move outward. The inner parts of the system are generally missing those materials that could not condense (form a solid) at the high temperatures found near the Sun. However, there are (again) important exceptions to the general pattern. For example, it is difficult to explain the presence of water on Earth and Mars if these planets formed in a region where the temperature was too hot for ice to condense, unless the ice or water was brought in later from cooler regions. The extreme example is the observation that there are polar deposits of ice on both Mercury and the Moon; these are almost certainly formed and maintained by occasional comet impacts.
As far as age is concerned, we discussed that radioactive dating demonstrates that some rocks on the surface of Earth have been present for at least 3.8 billion years, and that certain lunar samples are 4.4 billion years old. The primitive meteorites all have radioactive ages near 4.5 billion years. The age of these unaltered building blocks is considered the age of the planetary system. The similarity of the measured ages tells us that planets formed and their crusts cooled within a few tens of millions of years (at most) of the beginning of the solar system. Further, detailed examination of primitive meteorites indicates that they are made primarily from material that condensed or coagulated out of a hot gas; few identifiable fragments appear to have survived from before this hot-vapor stage 4.5 billion years ago.
The Solar Nebula
All the foregoing constraints are consistent with the general idea, introduced in Other Worlds: An Introduction to the Solar System, that the solar system formed 4.5 billion years ago out of a rotating cloud of vapor and dust—which we call the solar nebula —with an initial composition similar to that of the Sun today. As the solar nebula collapsed under its own gravity, material fell toward the center, where things became more and more concentrated and hot. Increasing temperatures in the shrinking nebula vaporized most of the solid material that was originally present.
At the same time, the collapsing nebula began to rotate faster through the conservation of angular momentum (see the Orbits and Gravity and Earth, Moon, and Sky chapters). Like a figure skater pulling her arms in to spin faster, the shrinking cloud spun more quickly as time went on. Now, think about how a round object spins. Close to the poles, the spin rate is slow, and it gets faster as you get closer to the equator. In the same way, near the poles of the nebula, where orbits were slow, the nebular material fell directly into the center. Faster moving material, on the other hand, collapsed into a flat disk revolving around the central object (Figure 14.11). The existence of this disk-shaped rotating nebula explains the primary motions in the solar system that we discussed in the previous section. And since they formed from a rotating disk, the planets all orbit the same way.
Picture the solar nebula at the end of the collapse phase, when it was at its hottest. With no more gravitational energy (from material falling in) to heat it, most of the nebula began to cool. The material in the center, however, where it was hottest and most crowded, formed a star that maintained high temperatures in its immediate neighborhood by producing its own energy. Turbulent motions and magnetic fields within the disk can drain away angular momentum, robbing the disk material of some of its spin. This allowed some material to continue to fall into the growing star, while the rest of the disk gradually stabilized.
The temperature within the disk decreased with increasing distance from the Sun, much as the planets’ temperatures vary with position today. As the disk cooled, the gases interacted chemically to produce compounds; eventually these compounds condensed into liquid droplets or solid grains. This is similar to the process by which raindrops on Earth condense from moist air as it rises over a mountain.
Let’s look in more detail at how material condensed at different places in the maturing disk (Figure 14.12). The first materials to form solid grains were the metals and various rock-forming silicates. As the temperature dropped, these were joined throughout much of the solar nebula by sulfur compounds and by carbon- and water-rich silicates, such as those now found abundantly among the asteroids. However, in the inner parts of the disk, the temperature never dropped low enough for such materials as ice or carbonaceous organic compounds to condense, so they were lacking on the innermost planets.
Far from the Sun, cooler temperatures allowed the oxygen to combine with hydrogen and condense in the form of water (H 2 O) ice. Beyond the orbit of Saturn, carbon and nitrogen combined with hydrogen to make ices such as methane (CH 4 ) and ammonia (NH 3 ). This sequence of events explains the basic chemical composition differences among various regions of the solar system.
We can use the concept of angular momentum to trace the evolution of the collapsing solar nebula. The angular momentum of an object is proportional to the square of its size (diameter) divided by its period of rotation
Solution
We are given that the final diameter of the solar nebula is about 80 AU. Noting the initial state before the collapse and the final state at Pluto’s orbit, then
With P initial equal to 1,000,000 years, P final , the new rotation period, is 64 years. This is a lot shorter than the actual time Pluto takes to go around the Sun, but it gives you a sense of the kind of speeding up the conservation of angular momentum can produce. As we noted earlier, other mechanisms helped the material in the disk lose angular momentum before the planets fully formed.
What would the rotation period of the nebula in our example be when it had shrunk to the size of Jupiter’s orbit?
- Answer
-
The period of the rotating nebula is inversely proportional to . As we have just seen, Initially, we have P initial = 10 6 yr and D initial = 10 4 AU. Then, if D final is in AU, P final (in years) is given by If Jupiter’s orbit has a radius of 5.2 AU, then the diameter is 10.4 AU. The period is then 1.08 years.
Formation of the Terrestrial Planets
The grains that condensed in the solar nebula rather quickly joined into larger and larger chunks, until most of the solid material was in the form of planetesimals, chunks a few kilometers to a few tens of kilometers in diameter. Some planetesimals still survive today as comets and asteroids. Others have left their imprint on the cratered surfaces of many of the worlds we studied in earlier chapters. A substantial step up in size is required, however, to go from planetesimal to planet.
Some planetesimals were large enough to attract their neighbors gravitationally and thus to grow by the process called accretion . While the intermediate steps are not well understood, ultimately several dozen centers of accretion seem to have grown in the inner solar system. Each of these attracted surrounding planetesimals until it had acquired a mass similar to that of Mercury or Mars. At this stage, we may think of these objects as protoplanets —“not quite ready for prime time” planets.
Each of these protoplanet s continued to grow by the accretion of planetesimals. Every incoming planetesimal was accelerated by the gravity of the protoplanet, striking with enough energy to melt both the projectile and a part of the impact area. Soon the entire protoplanet was heated to above the melting temperature of rocks. The result was planetary differentiation , with heavier metals sinking toward the core and lighter silicates rising toward the surface. As they were heated, the inner protoplanets lost some of their more volatile constituents (the lighter gases), leaving more of the heavier elements and compounds behind.
Formation of the Giant Planets
In the outer solar system, where the available raw materials included ices as well as rocks, the protoplanets grew to be much larger, with masses ten times greater than Earth. These protoplanets of the outer solar system were so large that they were able to attract and hold the surrounding gas. As the hydrogen and helium rapidly collapsed onto their cores, the giant planets were heated by the energy of contraction. But although these giant planets got hotter than their terrestrial siblings, they were far too small to raise their central temperatures and pressures to the point where nuclear reactions could begin (and it is such reactions that give us our definition of a star). After glowing dull red for a few thousand years, the giant planets gradually cooled to their present state (Figure 14.13).
The collapse of gas from the nebula onto the cores of the giant planets explains how these objects acquired nearly the same hydrogen-rich composition as the Sun. The process was most efficient for Jupiter and Saturn; hence, their compositions are most nearly “cosmic.” Much less gas was captured by Uranus and Neptune, which is why these two planets have compositions dominated by the icy and rocky building blocks that made up their large cores rather than by hydrogen and helium. The initial formation period ended when much of the available raw material was used up and the solar wind (the flow of atomic particles) from the young Sun blew away the remaining supply of lighter gases.
Further Evolution of the System
All the processes we have just described, from the collapse of the solar nebula to the formation of protoplanets, took place within a few million years. However, the story of the formation of the solar system was not complete at this stage; there were many planetesimals and other debris that did not initially accumulate to form the planets. What was their fate?
The comets visible to us today are merely the tip of the cosmic iceberg (if you’ll pardon the pun). Most comets are believed to be in the Oort cloud, far from the region of the planets. Additional comets and icy dwarf planets are in the Kuiper belt, which stretches beyond the orbit of Neptune. These icy pieces probably formed near the present orbits of Uranus and Neptune but were ejected from their initial orbits by the gravitational influence of the giant planets.
In the inner parts of the system, remnant planetesimals and perhaps several dozen protoplanets continued to whiz about. Over the vast span of time we are discussing, collisions among these objects were inevitable. Giant impacts at this stage may have stripped Mercury of part of its mantle and crust, reversed the rotation of Venus, and broke off part of Earth to create the Moon (all events we discussed in other chapters).
Smaller-scale impacts also added mass to the inner protoplanets. Because the gravity of the giant planets could “stir up” the orbits of the planetesimals, the material impacting on the inner protoplanets could have come from almost anywhere within the solar system. In contrast to the previous stage of accretion, therefore, this new material did not represent just a narrow range of compositions.
As a result, much of the debris striking the inner planets was ice-rich material that had condensed in the outer part of the solar nebula. As this comet-like bombardment progressed, Earth accumulated the water and various organic compounds that would later be critical to the formation of life. Mars and Venus probably also acquired abundant water and organic materials from the same source, as Mercury and the Moon are still doing to form their icy polar caps.
Gradually, as the planets swept up or ejected the remaining debris, most of the planetesimals disappeared. In two regions, however, stable orbits are possible where leftover planetesimals could avoid impacting the planets or being ejected from the system. These regions are the asteroid belt between Mars and Jupiter and the Kuiper belt beyond Neptune. The planetesimals (and their fragments) that survive in these special locations are what we now call asteroids, comets, and trans-neptunian objects.
Astronomers used to think that the solar system that emerged from this early evolution was similar to what we see today. Detailed recent studies of the orbits of the planets and asteroids, however, suggest that there were more violent events soon afterward, perhaps involving substantial changes in the orbits of Jupiter and Saturn. These two giant planets control, through their gravity, the distribution of asteroids. Working backward from our present solar system, it appears that orbital changes took place during the first few hundred million years. One consequence may have been scattering of asteroids into the inner solar system, causing the period of “heavy bombardment” recorded in the oldest lunar craters.


2.3: Charlotte Brontë, excerpt from Jane Eyre (1847)
Charlotte Brontë, excerpt from Jane Eyre (1847)
Jeanette A. Laredo
Chapter 1
There was no possibility of taking a walk that day. We had been wandering, indeed, in the leafless shrubbery an hour in the morning; but since dinner (Mrs. Reed, when there was no company, dined early) the cold winter wind had brought with it clouds so sombre, and a rain so penetrating, that further out-door exercise was now out of the question.
I was glad of it: I never liked long walks, especially on chilly afternoons: dreadful to me was the coming home in the raw twilight, with nipped fingers and toes, and a heart saddened by the chidings of Bessie, the nurse, and humbled by the consciousness of my physical inferiority to Eliza, John, and Georgiana Reed.
The said Eliza, John, and Georgiana were now clustered round their mama in the drawing-room: she lay reclined on a sofa by the fireside, and with her darlings about her (for the time neither quarrelling nor crying) looked perfectly happy. Me, she had dispensed from joining the group; saying, “She regretted to be under the necessity of keeping me at a distance; but that until she heard from Bessie, and could discover by her own observation, that I was endeavouring in good earnest to acquire a more sociable and childlike disposition, a more attractive and sprightly manner—something lighter, franker, more natural, as it were—she really must exclude me from privileges intended only for contented, happy, little children.”
“What does Bessie say I have done?” I asked.
“Jane, I don’t like cavillers or questioners; besides, there is something truly forbidding in a child taking up her elders in that manner. Be seated somewhere; and until you can speak pleasantly, remain silent.”
A breakfast-room adjoined the drawing-room, I slipped in there. It contained a bookcase: I soon possessed myself of a volume, taking care that it should be one stored with pictures. I mounted into the window-seat: gathering up my feet, I sat cross-legged, like a Turk; and, having drawn the red moreen curtain nearly close, I was shrined in double retirement.
Folds of scarlet drapery shut in my view to the right hand; to the left were the clear panes of glass, protecting, but not separating me from the drear November day. At intervals, while turning over the leaves of my book, I studied the aspect of that winter afternoon. Afar, it offered a pale blank of mist and cloud; near a scene of wet lawn and storm-beat shrub, with ceaseless rain sweeping away wildly before a long and lamentable blast.
I returned to my book—Bewick’s History of British Birds: the letterpress thereof I cared little for, generally speaking; and yet there were certain introductory pages that, child as I was, I could not pass quite as a blank. They were those which treat of the haunts of sea-fowl; of “the solitary rocks and promontories” by them only inhabited; of the coast of Norway, studded with isles from its southern extremity, the Lindeness, or Naze, to the North Cape—
“Where the Northern Ocean, in vast whirls,
Boils round the naked, melancholy isles
Of farthest Thule; and the Atlantic surge
Pours in among the stormy Hebrides.”
Nor could I pass unnoticed the suggestion of the bleak shores of Lapland, Siberia, Spitzbergen, Nova Zembla, Iceland, Greenland, with “the vast sweep of the Arctic Zone, and those forlorn regions of dreary space,—that reservoir of frost and snow, where firm fields of ice, the accumulation of centuries of winters, glazed in Alpine heights above heights, surround the pole, and concentre the multiplied rigours of extreme cold.” Of these death-white realms I formed an idea of my own: shadowy, like all the half-comprehended notions that float dim through children’s brains, but strangely impressive. The words in these introductory pages connected themselves with the succeeding vignettes, and gave significance to the rock standing up alone in a sea of billow and spray; to the broken boat stranded on a desolate coast; to the cold and ghastly moon glancing through bars of cloud at a wreck just sinking.
I cannot tell what sentiment haunted the quite solitary churchyard, with its inscribed headstone; its gate, its two trees, its low horizon, girdled by a broken wall, and its newly-risen crescent, attesting the hour of eventide.
The two ships becalmed on a torpid sea, I believed to be marine phantoms.
The fiend pinning down the thief’s pack behind him, I passed over quickly: it was an object of terror.
So was the black horned thing seated aloof on a rock, surveying a distant crowd surrounding a gallows.
Each picture told a story; mysterious often to my undeveloped understanding and imperfect feelings, yet ever profoundly interesting: as interesting as the tales Bessie sometimes narrated on winter evenings, when she chanced to be in good humour; and when, having brought her ironing-table to the nursery hearth, she allowed us to sit about it, and while she got up Mrs. Reed’s lace frills, and crimped her nightcap borders, fed our eager attention with passages of love and adventure taken from old fairy tales and other ballads; or (as at a later period I discovered) from the pages of Pamela, and Henry, Earl of Moreland.
With Bewick on my knee, I was then happy: happy at least in my way. I feared nothing but interruption, and that came too soon. The breakfast-room door opened.
“Boh! Madam Mope!” cried the voice of John Reed; then he paused: he found the room apparently empty.
“Where the dickens is she!” he continued. “Lizzy! Georgy! (calling to his sisters) Joan is not here: tell mama she is run out into the rain—bad animal!”
“It is well I drew the curtain,” thought I; and I wished fervently he might not discover my hiding-place: nor would John Reed have found it out himself; he was not quick either of vision or conception; but Eliza just put her head in at the door, and said at once—
“She is in the window-seat, to be sure, Jack.”
And I came out immediately, for I trembled at the idea of being dragged forth by the said Jack.
“What do you want?” I asked, with awkward diffidence.
“Say, ‘What do you want, Master Reed?’” was the answer. “I want you to come here;” and seating himself in an arm-chair, he intimated by a gesture that I was to approach and stand before him.
John Reed was a schoolboy of fourteen years old; four years older than I, for I was but ten: large and stout for his age, with a dingy and unwholesome skin; thick lineaments in a spacious visage, heavy limbs and large extremities. He gorged himself habitually at table, which made him bilious, and gave him a dim and bleared eye and flabby cheeks. He ought now to have been at school; but his mama had taken him home for a month or two, “on account of his delicate health.” Mr. Miles, the master, affirmed that he would do very well if he had fewer cakes and sweetmeats sent him from home; but the mother’s heart turned from an opinion so harsh, and inclined rather to the more refined idea that John’s sallowness was owing to over-application and, perhaps, to pining after home.
John had not much affection for his mother and sisters, and an antipathy to me. He bullied and punished me; not two or three times in the week, nor once or twice in the day, but continually: every nerve I had feared him, and every morsel of flesh in my bones shrank when he came near. There were moments when I was bewildered by the terror he inspired, because I had no appeal whatever against either his menaces or his inflictions; the servants did not like to offend their young master by taking my part against him, and Mrs. Reed was blind and deaf on the subject: she never saw him strike or heard him abuse me, though he did both now and then in her very presence, more frequently, however, behind her back.
Habitually obedient to John, I came up to his chair: he spent some three minutes in thrusting out his tongue at me as far as he could without damaging the roots: I knew he would soon strike, and while dreading the blow, I mused on the disgusting and ugly appearance of him who would presently deal it. I wonder if he read that notion in my face; for, all at once, without speaking, he struck suddenly and strongly. I tottered, and on regaining my equilibrium retired back a step or two from his chair.
“That is for your impudence in answering mama awhile since,” said he, “and for your sneaking way of getting behind curtains, and for the look you had in your eyes two minutes since, you rat!”
Accustomed to John Reed’s abuse, I never had an idea of replying to it; my care was how to endure the blow which would certainly follow the insult.
“What were you doing behind the curtain?” he asked.
“I was reading.”
“Show the book.”
I returned to the window and fetched it thence.
 Now, I’ll teach you to rummage my bookshelves: for they are mine; all the house belongs to me, or will do in a few years. Go and stand by the door, out of the way of the mirror and the windows.”
I did so, not at first aware what was his intention; but when I saw him lift and poise the book and stand in act to hurl it, I instinctively started aside with a cry of alarm: not soon enough, however; the volume was flung, it hit me, and I fell, striking my head against the door and cutting it. The cut bled, the pain was sharp: my terror had passed its climax; other feelings succeeded.
“Wicked and cruel boy!” I said. “You are like a murderer—you are like a slave-driver—you are like the Roman emperors!”
I had read Goldsmith’s History of Rome, and had formed my opinion of Nero, Caligula, etc. Also I had drawn parallels in silence, which I never thought thus to have declared aloud.
“What! what!” he cried. “Did she say that to me? Did you hear her, Eliza and Georgiana? Won’t I tell mama? but first—”
He ran headlong at me: I felt him grasp my hair and my shoulder: he had closed with a desperate thing. I really saw in him a tyrant, a murderer. I felt a drop or two of blood from my head trickle down my neck, and was sensible of somewhat pungent suffering: these sensations for the time predominated over fear, and I received him in frantic sort.  Rat!” and bellowed out aloud. Aid was near him: Eliza and Georgiana had run for Mrs. Reed, who was gone upstairs: she now came upon the scene, followed by Bessie and her maid Abbot. We were parted: I heard the words—
“Dear! dear!
Then Mrs. Reed subjoined—
“Take her away to the red-room, and lock her in there.” Four hands were immediately laid upon me, and I was borne upstairs.
Chapter 2
I resisted all the way: a new thing for me, and a circumstance which greatly strengthened the bad opinion Bessie and Miss Abbot were disposed to entertain of me. The fact is, I was a trifle beside myself; or rather out of myself, as the French would say: I was conscious that a moment’s mutiny had already rendered me liable to strange penalties, and, like any other rebel slave, I felt resolved, in my desperation, to go all lengths.
“Hold her arms, Miss Abbot: she’s like a mad cat.”
“For shame! for shame!” cried the lady’s-maid. “What shocking conduct, Miss Eyre, to strike a young gentleman, your benefactress’s son! Your young master.”
“Master! How is he my master?  There, sit down, and think over your wickedness.”
They had got me by this time into the apartment indicated by Mrs. Reed, and had thrust me upon a stool: my impulse was to rise from it like a spring; their two pair of hands arrested me instantly.
“If you don’t sit still, you must be tied down,” said Bessie. “Miss Abbot, lend me your garters; she would break mine directly.”
Miss Abbot turned to divest a stout leg of the necessary ligature. This preparation for bonds, and the additional ignominy it inferred, took a little of the excitement out of me.
“Don’t take them off,” I cried; “I will not stir.”
In guarantee whereof, I attached myself to my seat by my hands.
“Mind you don’t,” said Bessie; and when she had ascertained that I was really subsiding, she loosened her hold of me; then she and Miss Abbot stood with folded arms, looking darkly and doubtfully on my face, as incredulous of my sanity.
“She never did so before,” at last said Bessie, turning to the Abigail.
“But it was always in her,” was the reply. “I’ve told Missis often my opinion about the child, and Missis agreed with me. She’s an underhand little thing: I never saw a girl of her age with so much cover.”
Bessie answered not; but ere long, addressing me, she said—“You ought to be aware, Miss, that you are under obligations to Mrs. Reed: she keeps you: if she were to turn you off, you would have to go to the poorhouse.”
I had nothing to say to these words: they were not new to me: my very first recollections of existence included hints of the same kind. This reproach of my dependence had become a vague sing-song in my ear: very painful and crushing, but only half intelligible.  They will have a great deal of money, and you will have none: it is your place to be humble, and to try to make yourself agreeable to them.”
“What we tell you is for your good,” added Bessie, in no harsh voice, “you should try to be useful and pleasant, then, perhaps, you would have a home here; but if you become passionate and rude, Missis will send you away, I am sure.”
“Besides,” said Miss Abbot, “God will punish her: He might strike her dead in the midst of her tantrums, and then where would she go? Come, Bessie, we will leave her: I wouldn’t have her heart for anything. Say your prayers, Miss Eyre, when you are by yourself; for if you don’t repent, something bad might be permitted to come down the chimney and fetch you away.”
They went, shutting the door, and locking it behind them.
The red-room was a square chamber, very seldom slept in, I might say never, indeed, unless when a chance influx of visitors at Gateshead Hall rendered it necessary to turn to account all the accommodation it contained: yet it was one of the largest and stateliest chambers in the mansion. A bed supported on massive pillars of mahogany, hung with curtains of deep red damask, stood out like a tabernacle in the centre; the two large windows, with their blinds always drawn down, were half shrouded in festoons and falls of similar drapery; the carpet was red; the table at the foot of the bed was covered with a crimson cloth; the walls were a soft fawn colour with a blush of pink in it; the wardrobe, the toilet-table, the chairs were of darkly polished old mahogany. Out of these deep surrounding shades rose high, and glared white, the piled-up mattresses and pillows of the bed, spread with a snowy Marseilles counterpane. Scarcely less prominent was an ample cushioned easy-chair near the head of the bed, also white, with a footstool before it; and looking, as I thought, like a pale throne.
This room was chill, because it seldom had a fire; it was silent, because remote from the nursery and kitchen; solemn, because it was known to be so seldom entered. The house-maid alone came here on Saturdays, to wipe from the mirrors and the furniture a week’s quiet dust: and Mrs. Reed herself, at far intervals, visited it to review the contents of a certain secret drawer in the wardrobe, where were stored divers parchments, her jewel-casket, and a miniature of her deceased husband; and in those last words lies the secret of the red-room—the spell which kept it so lonely in spite of its grandeur.
Mr. Reed had been dead nine years: it was in this chamber he breathed his last; here he lay in state; hence his coffin was borne by the undertaker’s men; and, since that day, a sense of dreary consecration had guarded it from frequent intrusion.
My seat, to which Bessie and the bitter Miss Abbot had left me riveted, was a low ottoman near the marble chimney-piece; the bed rose before me; to my right hand there was the high, dark wardrobe, with subdued, broken reflections varying the gloss of its panels; to my left were the muffled windows; a great looking-glass between them repeated the vacant majesty of the bed and room. I was not quite sure whether they had locked the door; and when I dared move, I got up and went to see. Alas! yes: no jail was ever more secure. Returning, I had to cross before the looking-glass; my fascinated glance involuntarily explored the depth it revealed. All looked colder and darker in that visionary hollow than in reality: and the strange little figure there gazing at me, with a white face and arms specking the gloom, and glittering eyes of fear moving where all else was still, had the effect of a real spirit: I thought it like one of the tiny phantoms, half fairy, half imp, Bessie’s evening stories represented as coming out of lone, ferny dells in moors, and appearing before the eyes of belated travellers. I returned to my stool.

All John Reed’s violent tyrannies, all his sisters’ proud indifference, all his mother’s aversion, all the servants’ partiality, turned up in my disturbed mind like a dark deposit in a turbid well. Why was I always suffering, always browbeaten, always accused, for ever condemned? Why could I never please? Why was it useless to try to win any one’s favour? Eliza, who was headstrong and selfish, was respected. Georgiana, who had a spoiled temper, a very acrid spite, a captious and insolent carriage, was universally indulged. Her beauty, her pink cheeks and golden curls, seemed to give delight to all who looked at her, and to purchase indemnity for every fault. John no one thwarted, much less punished; though he twisted the necks of the pigeons, killed the little pea-chicks, set the dogs at the sheep, stripped the hothouse vines of their fruit, and broke the buds off the choicest plants in the conservatory: he called his mother “old girl,” too; sometimes reviled her for her dark skin, similar to his own; bluntly disregarded her wishes; not unfrequently tore and spoiled her silk attire; and he was still “her own darling.” I dared commit no fault: I strove to fulfil every duty; and I was termed naughty and tiresome, sullen and sneaking, from morning to noon, and from noon to night.
My head still ached and bled with the blow and fall I had received: no one had reproved John for wantonly striking me; and because I had turned against him to avert farther irrational violence, I was loaded with general opprobrium.
“Unjust!—unjust!” said my reason, forced by the agonising stimulus into precocious though transitory power: and Resolve, equally wrought up, instigated some strange expedient to achieve escape from insupportable oppression—as running away, or, if that could not be effected, never eating or drinking more, and letting myself die.
What a consternation of soul was mine that dreary afternoon! How all my brain was in tumult, and all my heart in insurrection! Yet in what darkness, what dense ignorance, was the mental battle fought! I could not answer the ceaseless inward question— why I thus suffered; now, at the distance of—I will not say how many years, I see it clearly.
I was a discord in Gateshead Hall: I was like nobody there; I had nothing in harmony with Mrs. Reed or her children, or her chosen vassalage. If they did not love me, in fact, as little did I love them. They were not bound to regard with affection a thing that could not sympathise with one amongst them; a heterogeneous thing, opposed to them in temperament, in capacity, in propensities; a useless thing, incapable of serving their interest, or adding to their pleasure; a noxious thing, cherishing the germs of indignation at their treatment, of contempt of their judgment. I know that had I been a sanguine, brilliant, careless, exacting, handsome, romping child—though equally dependent and friendless—Mrs. Reed would have endured my presence more complacently; her children would have entertained for me more of the cordiality of fellow-feeling; the servants would have been less prone to make me the scapegoat of the nursery.
Daylight began to forsake the red-room; it was past four o’clock, and the beclouded afternoon was tending to drear twilight. I heard the rain still beating continuously on the staircase window, and the wind howling in the grove behind the hall; I grew by degrees cold as a stone, and then my courage sank. My habitual mood of humiliation, self-doubt, forlorn depression, fell damp on the embers of my decaying ire. All said I was wicked, and perhaps I might be so; what thought had I been but just conceiving of starving myself to death? That certainly was a crime: and was I fit to die? Or was the vault under the chancel of Gateshead Church an inviting bourne? In such vault I had been told did Mr. Reed lie buried; and led by this thought to recall his idea, I dwelt on it with gathering dread. I could not remember him; but I knew that he was my own uncle—my mother’s brother—that he had taken me when a parentless infant to his house; and that in his last moments he had required a promise of Mrs. Reed that she would rear and maintain me as one of her own children. Mrs. Reed probably considered she had kept this promise; and so she had, I dare say, as well as her nature would permit her; but how could she really like an interloper not of her race, and unconnected with her, after her husband’s death, by any tie? It must have been most irksome to find herself bound by a hard-wrung pledge to stand in the stead of a parent to a strange child she could not love, and to see an uncongenial alien permanently intruded on her own family group.
A singular notion dawned upon me. I doubted not—never doubted—that if Mr. Reed had been alive he would have treated me kindly; and now, as I sat looking at the white bed and overshadowed walls—occasionally also turning a fascinated eye towards the dimly gleaning mirror—I began to recall what I had heard of dead men, troubled in their graves by the violation of their last wishes, revisiting the earth to punish the perjured and avenge the oppressed; and I thought Mr. Reed’s spirit, harassed by the wrongs of his sister’s child, might quit its abode—whether in the church vault or in the unknown world of the departed—and rise before me in this chamber. I wiped my tears and hushed my sobs, fearful lest any sign of violent grief might waken a preternatural voice to comfort me, or elicit from the gloom some haloed face, bending over me with strange pity. This idea, consolatory in theory, I felt would be terrible if realised: with all my might I endeavoured to stifle it—I endeavoured to be firm. Shaking my hair from my eyes, I lifted my head and tried to look boldly round the dark room; at this moment a light gleamed on the wall. Was it, I asked myself, a ray from the moon penetrating some aperture in the blind? No; moonlight was still, and this stirred; while I gazed, it glided up to the ceiling and quivered over my head. I can now conjecture readily that this streak of light was, in all likelihood, a gleam from a lantern carried by some one across the lawn: but then, prepared as my mind was for horror, shaken as my nerves were by agitation, I thought the swift darting beam was a herald of some coming vision from another world. My heart beat thick, my head grew hot; a sound filled my ears, which I deemed the rushing of wings; something seemed near me; I was oppressed, suffocated: endurance broke down; I rushed to the door and shook the lock in desperate effort. Steps came running along the outer passage; the key turned, Bessie and Abbot entered.
“Miss Eyre, are you ill?” said Bessie.
“What a dreadful noise! it went quite through me!” exclaimed Abbot.
“Take me out! Let me go into the nursery!” was my cry.
“What for? Are you hurt? Have you seen something?” again demanded Bessie.
“Oh! I saw a light, and I thought a ghost would come.” I had now got hold of Bessie’s hand, and she did not snatch it from me.
“She has screamed out on purpose,” declared Abbot, in some disgust. “And what a scream! If she had been in great pain one would have excused it, but she only wanted to bring us all here: I know her naughty tricks.”
“What is all this?” demanded another voice peremptorily; and Mrs. Reed came along the corridor, her cap flying wide, her gown rustling stormily. “Abbot and Bessie, I believe I gave orders that Jane Eyre should be left in the red-room till I came to her myself.”
“Miss Jane screamed so loud, ma’am,” pleaded Bessie.
“Let her go,” was the only answer. “Loose Bessie’s hand, child: you cannot succeed in getting out by these means, be assured. I abhor artifice, particularly in children; it is my duty to show you that tricks will not answer: you will now stay here an hour longer, and it is only on condition of perfect submission and stillness that I shall liberate you then.”
“O aunt! have pity! Forgive me! I cannot endure it—let me be punished some other way! I shall be killed if—”
“Silence! This violence is all most repulsive:” and so, no doubt, she felt it. I was a precocious actress in her eyes; she sincerely looked on me as a compound of virulent passions, mean spirit, and dangerous duplicity.
Bessie and Abbot having retreated, Mrs. Reed, impatient of my now frantic anguish and wild sobs, abruptly thrust me back and locked me in, without farther parley. I heard her sweeping away; and soon after she was gone, I suppose I had a species of fit: unconsciousness closed the scene.


16.7: Medical Specialists, Diagnostic Testing, and Procedures Related to the Nervous System
Medical Specialists
Neurology (noo-ROL-ŏ-jē) is the study of the nervous system. Psychiatry (sī-KĪ-ă-trē) is the study of disorders of the mind. Psychology (sī-KOL-ŏ-jē) is the study of the mind.
Neurologist
A neurologist (nū-RŎL-ō-jĭst) is a physician who specializes in the diagnosis and treatment of disorders and conditions related to the brain, spinal cord, nerves, and muscles. Neurosurgeons (nū-RŎ-sŭrj- ŭnz) perform surgeries on the nervous system.
Read additional information about neurologists on the American Academy of Neurology’s web page.
Psychiatrist
A psychiatrist (sī-KĪ-ă-trĭst) is a medical doctor who specializes in mental health and substance disorders. Because they are physicians, psychiatrists can order or perform a full range of medical laboratory and psychological tests. Mental health diagnoses are based on criteria established in Diagnostic and Statistical Manual of Mental Disorders (DSM-5 ), which contains descriptions, symptoms, and other criteria for diagnosing mental disorders. Psychiatrists prescribe a variety of treatments, including talk therapy, medications, psychosocial interventions, and other treatments such as electroconvulsive therapy (ē-lek-trō-kŏn-VŬL-sĭv THĔR-ă-pē) (ECT) , depending on the needs of each patient. ECT is the application of electrical currents to the brain, typically used to treat severe depression that has not responded to other treatments.
Read more information about psychiatrists on the American Psychiatric Association’s web page.
Psychologist
Psychologists (sī-KŎL-ō-jĭstz) are professionals with graduate degrees, and many have doctoral degrees (i.e., PhD, PsyD, or EdD). They specialize in helping people learn to cope with stressful situations, overcome substance use disorders, and manage chronic mental health disorders, and they also perform psychological tests.
Read more information about psychologists on the American Psychological Association’s web page .
Social Workers
Social workers (SŌ-shăl WŬR-kĕrz) help people prevent and cope with problems in their everyday lives. Social workers typically need a bachelor’s or master’s degree in social work (BSW or MSW) from an accredited program.
Read more about social workers on the Bureau of Labor Statistics’ web page.
Counselors
Substance use and mental health counselors advise people on issues such as those relating to alcoholism, substance use disorders, or depression. Education and training requirements vary for entering these occupations by state. For example, in Wisconsin there are associate degree programs available in substance use disorder counseling. Mental health counseling typically requires a master’s degree.
Read more about counselors on the Bureau of Labor Statistics’ web page.
Diagnostic Tests Related to the Nervous System
Cerebral Angiography
Cerebral angiography (SĚR-ă-brĭl, an-jē-OG-ră-fē) uses X-rays and special dye to see how blood flows through the brain. Specially trained health care providers perform this procedure in an operating room. During the procedure, a provider inserts a catheter into an artery in the wrist or groin area, injects contrast material through the catheter, and then takes X-rays of the blood vessels. Cerebral angiograms provide more detailed images of blood vessels than other imaging tests, like CT or MRI scans. [1]
Electroencephalogram (EEG)
An electroencephalogram (ĕ-lek-trō-ĕn-SEF-ă-lŏ-gram) (EEG) is a test to measure the electrical activity of the brain. The test is performed by an electroencephalogram (EEG) technologist in a laboratory, health care provider’s office, or hospital. Flat metal disks called electrodes are placed on many spots on the scalp. The electrodes are connected by wires to a recording machine that changes the electrical signals into patterns that can be seen on a monitor or drawn on paper. [2] See Figure 16.14 [3] for an image of an EEG.
Electromyography (EMG)
An electromyogram (ē-lĕk-trō-mī-Ŏ-grăm) (EMG) is a diagnostic procedure that assesses the function of nerve cells that control muscles. Electrodes, either attached to the skin or inserted into the muscle, record electrical impulses. An EMG can identify functional problems with the peripheral nerves, muscles, or with the signals between the nerves and the muscles. A nerve conduction study, another part of an EMG, uses surface electrodes applied to the skin to measure the speed and strength of signals traveling between two or more points. EMG results are used to diagnose muscle and nerve disorders. [4]
Lumbar Puncture (Spinal Tap)
A lumbar puncture (LŬM-băr PŬNK-chŭr), which is also called a spinal tap, is a test used to diagnose nervous system infections and other conditions. During a lumbar puncture, a needle is inserted into the space between two vertebrae in the lumbar region to remove a sample of cerebrospinal fluid (CSF). CSF is the fluid that surrounds the brain and spinal cord to protect them from injury. [5] See Figure 16.15 [6] for an illustration of a lu mbar puncture.
Procedures Related to the Nervous System
Carotid Endarterectomy
A carotid endarterectomy (kă-rŏt-ĭd ĕnd-ăr-tĕr-ĔK-tŏ-mē) is the surgical removal of plaque blocking the carotid arteries in the neck. The carotid arteries are the main blood vessels that carry oxygen and blood to the brain. This procedure is performed to prevent or treat a stroke. [7]
- Cleveland Clinic. (2023, August 8). Cerebral angiogram. my.clevelandclinic.org/health/diagnostics/13476-cerebral-angiogram ↵
- A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2023. EEG; [reviewed 2023, Jan 1; cited 2023, Dec 7). https://medlineplus.gov/ency/article/003931.htm ↵
- “ Three_quarter_view_of_EEG_subject.jpg ” by Chris Hope and shared by Tim Sheerman-Chase is licensed under CC BY 2.0 ↵
- Mayo Clinic. (2019, May 21). Electromyography (EMG) . https://www.mayoclinic.org/tests-procedures/emg/about/pac-20393913 ↵
- Mayo Clinic. (2022, April 30). Lumbar puncture (spinal tap). www.mayoclinic.org/tests-procedures/lumbar-puncture/about/pac-20394631 ↵
- “ Diagram_showing_how_you_have_a_lumbar_puncture_CRUK_157.svg ” by Cancer Research UK is licensed under CC BY-SA 4.0 ↵
- Johns Hopkins Medicine. (n.d.). Carotid endarterectomy . www.hopkinsmedicine.org/health/treatment-tests-and-therapies/carotid-endarterectomy ↵