Disciplines and Methods. Emotion. Historical Perspective on Emotion versus Cognition. Why emotion in cognitive science? recent work (LeDoux, Damasio)

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1 Emotion Why emotion in cognitive science? recent work (LeDoux, Damasio) emotion closely tied to thought perception decision making learning unconscious computations underlie conscious decision Disciplines and Methods clinical and counseling psychologists introspection and psychoanalytic- unconscious physiologists response of body to stress psychiatrists emotions out of control neurologists often the first screening experimental psychologists affects on behavior, social interaction, effectiveness neuropsychologists Neurophysiologists studying emotion in animals (Le Doux) Methods fear conditioning anatomical tracing lesion and ablation behavior Historical Perspective on Emotion versus Cognition Why not part of cognitive science? Roots of the ideas (LeDoux) Greek preoccupation with rationality Man as a rational thinker Freud - the unconscious is Philosophy - the modern mind preoccupation with consciousness Decartes - I think therefore I am humans are conscious humans are above animals home of primitive instinct link between humans and animals an enormously important component of the human psyche rationality is there to suppress. 1

2 Cognitive science resurrects the Greek idea of mind rationality and its side-kick - language human mind carefully engineered machine time to reevaluate science of mind failure of logical computation emphasis on neural computation evolution of adaptive systems progress of neuroscience no place for animal mind Le Doux s Perspective on Emotion not just 1 thing each emotion best studied in isolation fear - different brain areas, different functions disgust happiness depression/sadness Emotional behavior highly conserved through evolution 4 F s fight flight feeding and. Emotional responses freezing, heart rate, autonomic etc. When emotions occur in animals with consciousness.. emotions are experienced consciously generated by unconscious processes once aroused -> feelings conscious post-hoc analysis love, annoyance, anger basically cognitive Labeled conscious feelings, like love, hate, etc. red herrings not worthy of scientific study part of the post-hoc analyses 2

3 Emotion can be studied with animal models animal and human brains more comparable here than anywhere else! Emotional feelings qualitatively same a any other conscious state That is an apple - ah ha! I m mad! Emotions happen to us passively though we can try to manipulate them Emotions powerful behavioral motivators love, hurt, anger, insult - war, etc. Where in the brain is emotion? lesion/ablation approach decorticate animals showed normal emotion cats - provoked crouched, etc. autonomic arousal pupil dilation blood pressure increases piloerection still somewhat abnormal unregulated. 3

4 Cannon and Bard (29) Papez Circuit - Limbic Brain Herrick s idea s (early 20th century) brain evolution lateral surface -phylogentically newer medial part - phylogenetically older Stream of Feeling stimulus Stream of Thought stimulus thalamus thalamus hypothalamus cortex body reaction Emotion from integration circuit stimulus thalamus cortex cingulate hippocampus hypothalamus thalamus 4

5 Question If we are to study emotions individually. How many emotions are there? What are they? How do we decide they are separate? How many emotions? Ekman s list fear sadness happiness anger disgust surprise How many emotions? Study emotions individually fear - phobias sadness - depression happiness - mania anger - aggression disgust - OCD LeDoux s working hypothesis If correct that they are different systems good choice If not nothing lost by focusing on one Why Fear? pervasive and diverse in humans predator, etc. intellectually-based existential fear prominent and diverse in psychopathology phobias snakes, cats, heights, open spaces, social situations... Expressed similarly in humans and animals withdraw immobility (freezing) defensive aggression submission 5

6 Repertoire startle orientation freeze, flight, or attack cat and rat first rat startles, next orients,.. If far -> flee If close ->freeze If unsuccessful - vocalize and attack Fear conditioning standard classical conditioning learning to pair a previously objective stimulus e.g., tone, etc. to a painful outcome.. the tone elicits fear without the painful outcome. A tool for studying emotion in animals... fruit fly marine snail fish lizard pigeon rabbit rat Fear Conditioning cat dog macaque human... Rat fear condition rat to sound-shock pair Which parts of the auditory system required? dissect out the neuro-pathways Auditory cortex damage did not extinguish conditioning Where else? thalamus (MGN)??? anatomical tracers from MGN reveals projections to 4 areas... 6

7 Systematically ablate each area in turn result clear amygdala destruction no fear conditioning So what does the amygdala do? Find areas to which the amygdala projects anatomical forward tracing methods Activates body response Conclusions and Implications fear can bypass the neocortex Low road for speed! 7

8 Summary -What is an emotion? a brain process physiological reaction to stimulus psychological reaction to a perception danger, life-altering event system of drives, actions, fulfillment drives - stimulus -> glucose drop, etc action - eat satisfaction - contentment primary emotions Taxonomy hard-wired through limbic system stimulus activates system associatively conditioned innate -? (facial expressions) physiological response hypothalamus - endochrine, neurotransmitters internal response (ANS) Taxonomy secondary emotions conscious deliberate cognitive evaluation possible simultaneous activation of limbic primary route thereafter Decision-making and Emotion A Case Study Phineas Gage accident - damage to frontal cortex Harlow s study Pre-accident responsible, good guy, leadership qualities, polite Post-accident inability to plan, make good decisions, social sense otherwise cognitively and perceptually intact Emotion and Human Decision-making 8

9 3D reconstruction of damage Gage (H. Damasio) prefrontal cortex bilaterally ventral and inner surfaces affected external surfaces preserved - working memory ventromedial known to be involved in decision-making Modern Phineas Gage Elliot brain tumor patient ventromedial prefrontal damage post-surgery language, mathematics, MMPI couldn t make a good decision - like Gage Standard Tests for Elliot IQ > normal Wechsler adult intelligence scale > normal digit spans, etc. language comprehension > normal Benton face matching task - fine all other perceptual tests - normal Standard Frontal Lobe Tests Wisconsin card sort task cards that can be sorted by color or form, etc person must switch criteria Elliot did fine Tests with incomplete knowledge How many giraffes are there in New York City? Elliot normal Change of perspective Began to notice the disaffected state of Elliot failed to see evidence of any emotion later test (Tranel) emotion-packed images Elliot recognized the emotion he had felt previously but was unaffected. Dissecting the decision process Does the impairment in decision making relate to the impairment in feeling? 9

10 Tests for Elliot decision-making read problem descriptions specify alternatives excellent maybe he doesn t understand consequences consequence prediction x -> y read decision descriptions predict what follows excellent maybe he can t initiate the process means-end analysis given a goal - asked to design a way to reach scenarios from personal and social domain excellent moral reasoning test given a difficult moral problem - Kohlberg test must choose lessor of two evils, etc. excellent maybe he can t consider right-wrong All said and done.. Elliot replies: but I still wouldn t know what to do! Emotion and Reasoning Somatic marker hypothesis (Damasio) decisions involve a body-based marker that is the result of a secondary emotion 10

11 decide who to vote for what to major in to pursue a friendship or romance whether or not to fly in bad weather what % of money to put in stocks Possibilities pure reason hypothesis generate a cost-benefit analysis decide the option with the cost-benefit ration situations complex, and quantification difficult These are seen with a conscious evaluative and logical basis. Possibilities Somatic marker hypothesis associative connection to previous experience BEFORE - cost-benefit gives a gut feeling positive negative prescreens possibilities.. 11