Fight or Flight Response

Fight or flight response is not useful in modern life.

Accuse stressors are not as common as chronic stressors, which cause high blood pressure and lowered immune response.

Acute stressors: adrenaline

Causes increased heart rate. blood pressure and breathing rate. Release of glucose and fats, supplying energy.

HPA Axis: Pituitary Gland

Corticotrophin-releasing hormone causes the pituitary gland to release adrenocorticotrophic hormone which is transported to the adrenal glands.

Befriending

Females forming protective alliances with other women.

Tend and Befriend response

Females more likely to show this response, which evolved in the context of women being the primary caregiver, and not fleeing so not to put offspring at risk.

Tending

Females protecting themselves and their young.

Gray 1988

Fight or flight is not the initial response to a threat, instead they show a freeze response. Freezing focuses attention, allowing them to make the best response.

Lee and Harley 2012

Genetic basis for genetic differences in responses to threat. Men have the SRY gene, women do not, preventing fight or flight response.

HPA Axis: Hypothalamus

Hypothalamus releases corticotrophin-releasing hormone to the sympathetic nervous system.

Response to chronic stressors

If the threat continues, HPA axis is activated.

Von Dawans et al 2012

Men do not just have a fight or flight response. Study found acute stressors can lead to greater cooperation and friendly behaviour in men.

Chronic stressors

Ongoing stress

Acute stressors: parasympathetic nervous system

Reduces stress response once threat has passed by slowing heart rate and reducing blood pressure.

Cortisol

Results in an energy burst, lower pain sensitivity and impaired cognitive processing.

Acute stressors: sympathetic nervous system

SNS is sends a signal to the adrenal medulla, which releases adrenaline into the bloodstream.

Amygdala in a stress response

Sends a distress signal to the hypothalamus, which communicates with the body through the sympathetic nervous system.

Acute stressors

Short term stress

HPA Axis: Adrenal Glands

Stimulates the adrenal cortex to release the hormone cortisol

What is a fight or flight response?

Survival mechanism so we can react to life-threatening situations