A state of physiological or psychological strain caused

A state of physiological or psychological strain caused by adverse stimuli (physical, mental, internal or external) that tend to disturb the functioning of an organism. www. psychlotron. org. uk What is Stress?

Sudden and severe stress generally produces: n n n Increase in heart rate Alterations in digestive activity Skin becomes pale Sweating increases Muscular tremors These responses are produced by the Hypothalamic-Pituitary-Adrenal Axis (HPAA) www. psychlotron. org. uk Physiological Stress Response

Hypothalamus Pituitary gland Sympathetic ganglia The stress response occurs when we are exposed to some sort of threat. It involves co-ordinated responses from a number of different systems and structures Adrenal cortex Adrenal Medulla Finish www. psychlotron. org. uk Physiological Stress Response

Hypothalamus Pituitary gland Sympathetic ganglia Adrenal cortex The hypothalamus is in charge of the stress response. When a stress response is triggered, it sends signals to two other structures: the pituitary gland, and the sympathetic ganglia. Adrenal Medulla Finish www. psychlotron. org. uk The Hypothalamus

Hypothalamus Pituitary gland Sympathetic ganglia The pituitary gland controls the glands of the endocrine system. When activated by the hypothalamus it releases ACTH, which activates the adrenal cortex. Adrenal cortex Adrenal Medulla Finish www. psychlotron. org. uk The Pituitary Gland

Hypothalamus Pituitary gland Sympathetic ganglia Adrenal cortex The sympathetic ganglia are connected to the internal organs. When activated they affect the functioning of the lungs, heart and digestive system. They are also connected to the adrenal medulla Adrenal Medulla Finish www. psychlotron. org. uk The Sympathetic Ganglia

Hypothalamus Pituitary gland Sympathetic ganglia The adrenal cortex releases chemicals called corticosteriods. These have a number of functions including releasing stored glucose and controlling swelling after injury. Adrenal cortex Adrenal Medulla Finish www. psychlotron. org. uk The Adrenal Cortex

Hypothalamus Pituitary gland Sympathetic ganglia The adrenal medulla releases adrenaline. This hormone stimulates the sympathetic ganglia, keeping their activity at a high level. Adrenal cortex Adrenal Medulla Finish www. psychlotron. org. uk The Adrenal Medulla

Increase oxygen intake Release stored glucose Divert resources away from digestion Ready to expend energy, either by fighting or by running away www. psychlotron. org. uk Fight or Flight Response

An early evolutionary adaptation that is useful in dealing with physical threats Helps us deal with short-term problems that can be solved by fighting or running Unfortunately, many of the threats we face in our society do not fall into these categories… www. psychlotron. org. uk The Fight or Flight Response