Chapter 8 Emotion and the Nervous System Pages 226 240 Distinctive patterns of autonomic activation among different emotions Anger and sadness both elevate heart rate but only anger involves also motor activation Facial expressions as a source of emotional feedback Smiling and the pattern of contractions needed to move those muscles is more toward the innate side of the continuum but is an interaction of both innate and learned characteristics Ex smiling is the same across cultures as well as in babies born deaf blind Holding a pen in your mouth and the Far Side cartoons Control hold pen with lips judged as less funny Experimental hold pen with teeth and don t let lips touch pen judged as funnier approximates a smile which may cause you to feel happier could also be that this just makes you feel silly Both cognitive assessment of external stimuli and physiological feedback play a role in emotion Peripheral Nervous System Chart page 225 Central Nervous System Limbic System complex network of subcortical structures Hypothalamus Septal Nuclei Amygdala Electrical stimulation in animals produces threatening or defensive behaviors cat s hissing bared teeth and claws Electrical stimulation in humans evokes feelings of rage fear or pleasure Electrical stimulation in humans evokes feelings of pleasure particularly sexual Involved in perception of facial expressions of emotion especially fear Damage to amygdala removes fear and aggression in animals Stimulation produces fear and aggression Anti anxiety medications have some of their effects in the amygdala benzodiazepines seem to have more receptors in the amygdala as shown through PET scans Damaged amygdala patients do not respond emotionally to rewards and punishments disrupts learning Major role in Fear emotional reaction to a specific immediate threat Anxiety apprehension about a future and often uncertain event Anterior Cingulate Gyrus Prefrontal Cortex PFC Part of the cingulate gyrus combines emotional attentional and bodily information to bring about conscious emotional experience Stress Lot of connections with limbic system LS Use emotional info from LS for decision making Damage to PFC Blunts emotional responding Impairs ability to anticipate consequences of behavior long term consequences in particular Hemispheric Asymmetry Left and right cerebral hemispheres can differ in Anatomical structure structural asymmetry e g Broca s area larger in left hemisphere than right Function performed functional asymmetry e g left hemisphere more involved in linguistic functions than right hemisphere Right hemisphere more involved in emotional expression Facial expression of emotions Evidence in both humans and monkeys that the right is more involved with emotion than the left Emotional impairment following brain damage e g stroke patient unperturbed by having left side of body paralyzed Difficulty in recognizing emotions in others following brain damage facial expressions and or voice Condition in the environment that makes unusual demands on the organism e g threat failure etc Internal condition body s response to a stressful situation Adaptive Response Stressful situation activation of the sympathetic branch of the PNS helps the organism cope with short term stress Stressful situation activation of the Hypothalamus Pituitary Adrenal cortex axis HPA diagram in textbook page 234 Group of structures that increase activation and energy levels Hypothalamus Anterior Pituitary ACTH AdrenalCorticoTropic Hormone through blood Adrenal Cortex produce epinephrine and norepinephrine which increase heart rate and glucose availability Cortisol converts proteins to glucose increases fat availability and metabolism Short term stress increases immune system activity cells and cell products that protect the body against foreign substances bacteria viruses tumor cells Negative Effects of Stress long term Mostly due to the effects of cortisol over months and years Memory impairment appetite changes decreased sex drive and energy mood disruptions Decreased B cells T cells and natural killer cells