For example, dopamine plays a big role in starting movement, and the destruction of dopamine neurons in an area of the brain called the substantia nigra is what produces the symptoms of Parkinsonâs disease. Dopamine also plays an important role as a hormone, inhibiting prolactin to stop the release of breast milk.
Why are sunspots darker than the rest of the Sun? Sunspots appear dark (in visible light) because they are much cooler than the rest of the surface of the Sun. However, even though they appear dark, they are still very hot. Sunspots have temperatures around 6,300 Fahrenheit (~3,500 Celsius) while the surrounding surface of the sun has a temperature of about 10,000 Fahrenheit (5,500 Celsius). If a sunspot was alone in space, it would glow brightly.
Sunspots always appear in pairs and are intense magnetic fields (about 5,000 times greater than the Earth's magnetic field) that break through the surface. Field lines leave through one sunspot and re-enter through the other one. The magnetic field is caused by movements of gases in the sun's interior.Sunspot activity occurs as part of an 11-year cycle called the solar cycle where there are periods of maximum and minimum activity.t is not known what causes this 11-year cycle, but two hypotheses have been proposed: 1  Uneven rotation of the sun distorts and twists magnetic field lines in the interior. 2  The twisted field lines break through the surface forming sunspot pairs. 3  Eventually, the field lines break apart and sunspot activity decreases.