Fight or Flight response

• A sequence of activity within the body is triggered when the body prepares itself for defending (fight) or running away (flight)
• Process of the response

  1. Threat
  2. Amygdala mobilises - associating sensory signals with emotions associated with the fight or flight response
  3. Sends a distress signal to the hypothalamus that then communicates with the rest of the body via nervous system
• Stressors

  • Acute (sudden)
  • Chronic (ongoing)
• An acute stressor is from adrenaline

  • Heart rate increases to transfer blood to muscles, heart and vital organs
  • blood pressure and rate increases
  • Increases release of fats and blood sugar providing energy to body parts associated with fight or flight response
• Chronic stressor - HPA axis

  • Hypothalamus releases a chemical messenger in response to continued threat (corticotrophin releasing hormone / CRH)
  • CRH causes pituitary gland to release Adrenocorticotrophic hormone (ACTH) to the adrenal gland
  • The adrenal glands cortex gets stimulated by the ACTH to release several stress relieving hormones (cortisol)
  • If levels of cortisol rise above threshold, the hypothalamus and pituitary gland initiate a reduction in CRH and ACTH levels
• If our stress response is repeatedly activated, it can have impact on blood pressure - leading to physical damage in the blood vessels, and eventually heart disease
• High levels of cortisol , long term, can suppress the immune system, shutting down processes that fight infection
• Weakness - gender differences

  • Taylor et al (2000) suggested that females respond by tending through nurturing and protecting, as fleeing would put their offspring at risk (due to being primary caregivers to children)
  • Lee and Harley (2012) found evidence of a genetic basis for gender differences - the SRY gene found on the male chromosome primes the male to promote aggression
• Strength/weakness - alternative explanations

  • Gray (1988) proposed that the initial response to avoid confrontation. Most animals freeze to stop and consider their next move, focusing attention