unit 2 - nature vs nurture: the biology of behavior

Innate behavior

mostly genetic

learned behavior

mostly environment

coping styles

characterized by constant behavioral and neuroendocrine characteristics to stressors, some of which seem to be causally linked to each other

active responses

characterized by territorial control and aggression (type A)

• proactive coping

  • hypertension, atherosclerosis, tachyarrhythmia due to high sympathetic reactivity

  • gastric ulcers (worst when stress unpredictable)

  • more stereotypes

passive response

characterized by conservation withdrawal (type B)

• reactive coping

  • immune suppression (influenced largely via glucocorticoids)

HPA axis activity

basal cortisol concentration

• proactive = low

• reactive = normal

HAP axis reactivity

cortisol response

• proactive = low

• reactive = high

sympathetic reactivity

Epi/Norepi response

• proactive = high

• reactive = low

organizational effects

developmental

• actions are conserved evolutionarily, appears across a wide range of taxa

• e.g. oxytocin (maternal bonds), insulin (glucose metabolism), testosterone, estrogen

activational effects

• fast-acting, temporary changes in behavior

• e.g. epinephrine (adrenaline) for fight-flight response

acetylcholine

• only neurotransmitter used in motor division of somatic nervous system (voluntary control of skeletal muscles)

dopamine

important for desire to engage in action

• primarily responsible for ‘wanting’ and craving

endorphins

modulate mood and especially pleasure

• play a role in the initial rush of pleasure

• regulate pleasure by stimulating dopamine release