Tuesday April 15 y Brain Behavior Emotion emotion cognition action feeling Emotions Autonomic Arousal emotional situations arouse the autonomic nervous system each situation has own mixture f sympathetic and parasympathetic arousal fight or flight sympathetic outflow parasympathetic outflow rest and digest James Lange Theory JL Theory suggest that autonomic arousal and skeletal actions occurs in first in an emotion emotional feelings result from body s action panic attacks are marked by extreme sympathetic nervous system arousal rapid heartbeat fast breathing etc only if perceived as occurring spontaneously JL Theory leads to two predictions ppl w weak autonomic or skeletal response should feel less emotion increasing one s response should enhance an emotions event appraisal cognitive aspect action behavioral aspect including physiology emotional feeling feeling aspect Testing JL Theory research indicates paralyzed ppl report feeling emotion to the same degree as prior to their injury ppl w pure autonomic failure still report feeling emotion but less intensely pure autonomic failure output from autonomic nervous system to body fails theory suggests factors are involved in perception of emotion Botox and emotions botox blocks transmissions at synapses and nerve muscle junctions ppl w botox show slow time in reading unhappy sentences weaker than usual emotional responses after watching short videos 1 mobius syndrome neurological condition that affects the muscles that control facial expression and eye movement Tuesday April 15 y Human Emotions basic emotions anger fear disgust surprise happiness sadness work to satisfy emotions work to avoid aversions contemplating moral decisions activates the prefrontal cortex cingulate gyrus and amygdala Measuring emotional responses footbridge life boat hideout hospital dilemma increasing amygdala prefrontal cortex cingulate gyrus activity single emotion increases activity in various parts of the brain localization in the brain seems to exist for the emotion of disgust insular cortex strongly activated during exposure to stimuli as disgusting left frontal temporal lobes behavioral activation system approach marked by low to moderate arousal characterize either happiness or anger right frontal and temporal lobes increase attention and arousal inhibits action stimulates emotions such as fear and disgust ppl w greater activity in left hemisphere happier more outgoing friendlier damage to left hemisphere are better at detecting others emotions ppl w greater right hemisphere socially withdrawn less satisfied w life prone to unpleasant emotions damage to right temporal cortex causes problems in ability to identify emotions of others right hemisphere is inactive when ppl do not experience strong emotions ppl dont remember feeling them right hemisphere seems to be more responsive to emotional stimuli than then left what if you damage the prefrontal cortex leads to impulsive decision making without pausing to consider consequences stem from failure to anticipate unpleasantness of an outcome ex phineas gage 2 Tuesday April 15 y damage to ventromedial prefrontal cortex show decreased guilt limbic system includes the forebrain areas surrounding the thalamus cingulate gyrus part of limbic system cortex coordinates sensory input w emotions emotional responses to pain regulates aggressive behavior amygdala connect w hypothalamus stores memories associated w emotional event hippocampus memory amygdala emotion attack behavior is associated w increased activity in the corticomedial area of the amygdala environmental and genetic contributors to violence factors associated w increased violent tendencies include exposure to lead witness or victim of violence in childhood living in a violent neighborhood MZ twins are more violent have more criminal behavior Testosterone aggression hormones also influence aggressive behavior male aggressive behavior is influenced by testosterone men have higher testosterone levels higher violent rates Cocktail of peptides triple imbalance hypothesis violence depends on other chemicals besides testosterone notably cortisol and serotonin cortisol response to stress increases blood sugar suppresses the immune system aggression levels are highest when cortisol levels are low and testosterone are high serotonin violent impulses Valzelli study social isolation decreased serotonin turnover and increased aggressive behavior turnover amount of a neurotransmitter than is released and resynthesized by neurons 5 hydroxyindoleacetic acid 5 HIAA serotonin metabolite found in cerebrospinal fluid blood and urine that allows researchers to inter turnover rate high levels of 5 HIAA much serotonin release and turnover less aggressive low levels low serotonin release more aggressive 3 Tuesday April 15 y monkeys with high levels of 5 HIAA more likely to survive low serotonin turnover linked to ppl w history of violent behavior crime ppl who attempt suicide by violent means recurrent violent behaviors blood test does not enable reliable identification not applicable in normal population tryptophan and serotonin synthesis can alter serotonin genes control production of trytophan hydroxylase trytophan hydroxylase is the enzyme that converts tryptophan into serotonin Fear and anxiety amygdala one of the main areas for integrating both environmental and genetic influences and then regulating current levels of anxiety Amygdala and fear output from amygdala to hypothalamus controls autonomic fear responses axons extended from amygdala to the prefrontal cortex regulate approach avoidance responses damage to the amygdala interferes w learning of fear responses retention of fear responses previously learned interpreting or understanding stimuli w emotional consequences toxoplasma gondii causes small mammals to experience rewiring in the amygdala they become sexually attracted to cats approach the cat and get eaten by the cat also infect humans Long term fear bed nucleus of the stria terminalis regulates long term generalized emotional arousal Kluver bucy syndrome 4 Tuesday April 15 y kluver bucy syndrome temporal lobe fail to display normal fears hyperphagia pica hyperorality hypersexualisty visual agnosia studies on monkeys illustrate the effects of amygdala damage monkeys with the syndrome are calm and placid and display less than normal fear of snakes larger more dominant monkeys alters social behaviors decreased ability to interpret threat gestures non
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