Biopsychology: The Fight/Flight Response

What is Cortisol?

A stress hormone that gives us a quick burst of energy to deal with stress, though long term release can cause the immune system to be suppressed.

Stage 3 of the Hypothalamic Pituitary Adrenal Axis (HPA)

ACTH then travels via the bloodstream to the adrenal glands, for the adrenal cortex to activate

Stage 2 of the Fight/Flight Response in a Sudden Stressful Situation

Adrenaline is a hormone which increases heart rate and is released by the Adrenal Medulla. It constricts the blood vessels and increases blood flow for blood pressure to rise. Adrenaline releases glucose which provides the energy needed for the fight/flight response. The flow of blood is diverted away from the surface of the skin to allow more blood flow to muscles. Digestion is inhibited, as energy is needed for the immediate actions of either fighting the stressor or running away. This also increases blood flow to the brain and muscles, and increases respiration and sweating.

Stage 1 of the Hypothalamic Pituitary Adrenal Axis (HPA)

An event occurs and the hypothalamus in the brain registers the event and produces CRH (Corticotrophin Releasing Hormone)

Positive Evaluation Point No. 2 of the Fight/Flight Response

Baxter stated that a person must have well functioning adrenal glands for the fight/flight response to occur. Without functioning adrenal glands, it's impossible to produce the level of adrenaline needed for the response. This consequently proves that the adrenal glands are a important factor in the activation of the fight/flight response.

Stage 2 of the Hypothalamic Pituitary Adrenal Axis (HPA)

CRH then travels to the Anterior Pituitary Gland, and this gland releases ACTH

Negative Evaluation Point No. 3 of the Fight/Flight Response

Gray (1998) stated that the first actual response to a stressful situation is to 'freeze' while you assess the danger around you. This causes the person to become hyper vigilant, and thus may be a better way of dealing with a situation.

Negative Evaluation Point No. 2 of the Fight/Flight Response

If the Fight/Flight response is continually activated, it can cause a permanent rise in blood pressure that can damage blood vessels. This can lead to heart disease in the long term. Cortisol can assist the body in fighting viral infections, but too much of it can be harmful and suppress the immune system

Negative Evaluation Point No. 1 of the Fight/Flight Response

Taylor (2000) argues that females are more likely to 'tend and befriend', which means they protect themselves and their offspring by forming alliances with other women. Women also have the hormone oxytocin, which prevents them from having the flight response, because they're more likely to stay to protect their children.

Stage 4 of the Fight/Flight Response in a Sudden Stressful Situation

The Sympathetic Nervous System is activated, and the fight or flight response begins. Breathing and heart rate increase, sweating occurs, salivation stops, pupils dilate etc.

Stage 5 of the Hypothalamic Pituitary Adrenal Axis (HPA)

The activation of the Sympathetic Nervous System causes heart and breathing rate to increase, digestion and salivation to stop, sweating to occur and pupils to dilate.

Stage 4 of the Hypothalamic Pituitary Adrenal Axis (HPA)

The adrenal cortex produces Cortisol and Adrenaline

Stage 3 of the Fight/Flight Response in a Sudden Stressful Situation

The body is prepared for fight or flight

Fight/Flight Response

The fight or flight response is a survival mechanism which enables humans and animals to response quickly to stressful or life-threatening situations. 'Fight' means you deal with the stressor, whereas 'Flight' means you run away from it. Both reactions require a lot of energy, so the fight or flight response causes the body to respond by increasing heart and breathing rate.

Positive Evaluation Point No. 1 of the Fight/Flight Response

The fight/flight response enables a person to effectively deal with a stressful situation, and both the fight and flight options are good survival mechanisms that can be useful and adaptive.

What is Adrenaline?

The hormone that increases heart rate by activating the Sympathetic Nervous System.

Stage 1 of the Fight/Flight Response in a Sudden Stressful Situation

The stressor occurs and the hypothalamus in the brain responds

What is the Hypothalamic Pituitary Adrenal Axis?

This is a process which occurs when there is ongoing stress that is not sudden.

Negative Evaluation Point No. 4 of the Fight/Flight Response

Von Diwans (2012) has found evidence that even males 'tend and befriend', sometimes. This is because humans are a social species, thus forming alliances can help us thrive.