section_path: Physiological signs
section_name: Physiological signs
paragraph_text: Physiological signs
  
  Many physiological changes in the body are associated with fear, summarized as the fight-or-flight response. An innate response for coping with danger, it works by accelerating the breathing rate (hyperventilation), heart rate, vasoconstriction of the peripheral blood vessels leading to blood pooling, dilating the pupils, increasing muscle tension including the muscles attached to each hair follicle to contract and causing "goosebumps", or more clinically, piloerection (making a cold person warmer or a frightened animal look more impressive), sweating, increased blood glucose (hyperglycemia), increased serum calcium, increase in white blood cells called neutrophilic leukocytes, alertness leading to sleep disturbance and "butterflies in the stomach" (dyspepsia). This primitive mechanism may help an organism survive by either running away or fighting the danger. With the series of physiological changes, the consciousness realizes an emotion of fear.
  
  There are observable physical reactions in individuals who experience fear. An individual might experience a feeling of dizziness, lightheaded, like they are being choked, sweating, shortness of breath, vomiting or nausea, numbness or shaking and any other like symptoms. These bodily reactions informs the individual that they are afraid and should proceed to remove or get away from the stimulus that is causing that fear.