Stress can impact an individual both mentally and physically.
When presented with stress, the body responds by releasing hormones that will prepare it for the fight-or-flight response. The body responds to stress in specific physiological ways. When a threat or danger is perceived, the body responds by releasing hormones that will prepare it for the fight-or-flight response. The endocrine hormones have evolved to ensure that the body’s internal environment remains stable; however, stress can disrupt this stability. Stimuli that disrupt homeostasis in this way are known as stressors.
The fight or flight response causes blood from your skin, organs, and extremities is directed to the brain and larger muscles in preparation to fight the impending danger or flee from it. Also, your senses (especially vision and hearing) are heightened, glucose and fatty acids are released into the bloodstream for energy, and your immune and digestive systems all but shut down to provide you with the necessary energy to fight the stressor.
The hypothalamic–pituitary–adrenal axis (HPA axis) is a complex set of direct influences and feedback interactions among three endocrine glands: the hypothalamus, the pituitary gland, and the adrenal glands. The HPA axis is a significant part of the neuroendocrine system that, among other things, controls reactions to stress.
The HPA system reacts within a person’s brain, and it releases the hormone cortisol from the adrenal gland when a person is exposed to a stressor. Cortisol is most likely to be activated when a person is placed in a situation to be socially judged or evaluated, and therefore under extreme levels of stress. Higher and more prolonged levels of cortisol in the bloodstream are found in those suffering from chronic stress. High levels of cortisol also have an impact on the immune system by depressing the activity of white blood cells.
Psychosomatic disorders are a type of psychological disorder. They are physical problems with a psychological cause. For example, a person who is extremely anxious about public speaking might feel extremely nauseated or may find themselves unable to speak at all when faced with the prospect of presenting in front of a group.
Physiological reactions to stress can have a long-term impact on physical health. Stress is one of the leading precursors to long-term health issues. Backaches, stroke, heart disease, and peptic ulcers are just a few physical ailments that can arise when a person is under too much stress.
A person can also exhibit behavioral problems when under stress, such as aggression, substance abuse, absenteeism, poor decision making, lack of creativity, or even sabotage. Someone under stress may neglect their duties, impeding workflows and processes that impact others.
Another theory to address the response to stress was proposed in 1934, Hans Selye with rats and enlarged hormonal glands. Selye defined a series of symptoms in the experiments with the rats as the General Adaptation Syndrome, which consists of three stages: the alarm stage, the resistance stage, and the exhaustion stage. The alarm stage is similar to the fight-to-flight response, and the body mobilizes resources to react to the incoming noxious agent. The resistance forces will be built up when the noxious challenge is detected as continuing. The exhaustion stage will cause death if the body is unable to overcome the threat.
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Key Points
• The interactions of endocrine hormones that have evolved to stabilize the body’s internal environment can be disrupted by stress.
• Stressors are stimuli that disrupt homeostasis.
• The adrenal gland and hypothalamus coordinate the hormonal response to stress.
• Release of the stress hormone cortisol leads to biological changes in the body characteristic of stress.
• Although our bodies can respond to and deal with stress in the short term, long-term exposure to stress hormones can have detrimental effects.
• Individual distress manifests in three basic forms: psychological disorders, medical illnesses, and behavioral problems.
• When individuals suffer from a high degree of stress, overall efficiency can substantially decrease.
• In general, individual distress manifests in three basic forms: psychological disorders, medical illnesses, and behavioral problems.
• Physiological reactions to stress can have a long-term impact on physical health. Stress is one of the leading precursors to long-term health issues.
• A person can also exhibit behavioral problems when under stress, such as aggression, substance abuse, absenteeism, poor decision making, lack of creativity, or even sabotage.
Key Terms
Fight-or-flight response: a physiological reaction that occurs in response to a perceived harmful event, attack, or threat to survival
Homeostasis: the ability of a system or living organism to adjust its internal environment to maintain a stable equilibrium, such as the ability of warm-blooded animals to maintain a constant temperature
Hypothalamus: the region of the forebrain below the thalamus, forming the basal portion of the diencephalon; regulates body temperature and some metabolic processes, and governs the autonomic nervous system
Stressor: a source of stress
Cortisol: a steroid hormone produced in the adrenal glands associated with stress
General Adaptation Syndrome (GAS): a theory that demonstrated that stress that is perceived as a threat (distress) may be debilitating if it is continuous