Emotion, Feelings and Motivation Emotions Stress Stress Stress Emotions Brain Periphery Brain Emotions Brain Periphery Emotions Brain Emotions • Whether conscious feeling follows bodily changes (James-Lange) or bodily changes follow feeling ? Emotion & Feeling • “Emotion” sometimes is used to refer only to the bodily state (ie, the emotional state) and “feeling” is used to refer to conscious sensation • When frightened we not only feel afraid but also experience increased heart rate and respiration, dryness of the mouth, tense muscles, and sweaty palms James-Lange Theory (1880s) • James wrote: “We feel sorry because we cry, angry because we strike, afraid because we tremble.” A double-blind test Epinephrine Saline Watch a thrilling film Which group will rate a higher thrill in the film? Patients in whom the spinal cord has been accidentally severed appear to experience a reduction in the intensity of their emotions. Cannon's study of peripheral responses to intense emotion • fight-or-flight response (1920) • the physiological responses to emotionally significant stimuli are too undifferentiated to convey to the cortex specific, detailed information about the nature of an emotional event. Bard’s Experiments (1920s) Sham rage: animals with the whole cerebral cortex removed retain fully integrated emotional responses By progressive transections the coordinated response disappeared when the hypothalamus was included in the ablation Cnnon-Bard Theory • The Hypothalamus mediating both the cognitive and peripheral aspects of emotion SchachterSinger Schachter’s Cognitive Experiment (1960s) Epinephrine Saline Group 1 Group 2 Epinephrine Group 3 Saline Group 4 Epinephrine’s effects Epinephrine’s effects Informed Not Informed How nervous are you? How nervous are you? James-Lange Cannon-Bard Schachter Peripheral stimuli Peripheral stimuli Peripheral stimuli Hypothalamus Cognitive translation Emotional state: Emotional state: autonomic, endocrine, skeletomotor responses autonomic, endocrine, skeletomotor responses Conscious feelings & emtional state When the sound alone is given, it evokes physiological changes in blood pressure and freezing similar to those evoked by the sound and shock together (right) Fear and Amygdala • Electrical stimulation of the amygdala in humans produces feelings of fear and apprehension. • Bilateral lesions of the basolateral complex of the amygdala in experimental animals abolish this learned response to fear. • Patients with damage to the amygdala do not learn to fear the neutral sound even though most were consciously aware that the neutral sound and the offensive noise were paired together. James-Lange Cannon-Bard Schachter Neuroanatomy Peripheral stimuli Peripheral stimuli Peripheral stimuli Central or Peripheral sti Hypothalamus Cognitive translation amygdala Conscious feelings & emtional state Conscious feelings & emtional state Emotional state: Emotional state: autonomic, endocrine, skeletomotor responses autonomic, endocrine, skeletomotor responses The Hypothalamus Coordinates the Peripheral Expression of Emotional States • In anesthetized animals, Ranson (1932) evoked individual conceivable autonomic reaction by stimulating different regions of the hypothalamus • In 1940s, Walter Hess extended Ranson's approach to awake, unanesthetized cats and found that different parts of the hypothalamus produce characteristic constellations of reactions Stimuli from the cortex • In 1935 John Fulton and Carlyle Jacobsen first reported that removing the frontal cortex (lobotomy) had a calming effect in chimpanzees. Within a few months of Fulton and Jacobsen's report, Egas Moniz, a Portuguese neuropsychiatrist, performed the first prefrontal lobotomy in humans, isolating the orbital frontal cortex. The patients became tamed. Egas Moniz performed the first prefrontal lobotomy in humans in 1935.(1949 Nobel Prize) SchachterSinger Cahill & McGaugh’s Propranolol Experiments Saline Propranolol Watch an emotionally arousing short story No difference in the initial emotional reaction to the story A week or a month later Reduced emotional reaction to the story in the propranolol group Mood & Monoamines 1. 2. 3. Long-term use of reserpine may cause depression (1959) Some people got euphoric when treated with iproniazid (1952) Imipramine is an effective antidepressant (1958) A. Reserpine almost irreversibly blocks the uptake (and storage) of norepinephrine and dopamine into synaptic vesicles by inhibiting the Vesicular Monoamine Transporters Iproniazid inhibits synaptic monoamine oxidase Imipramine inhibit reuptake of norepinephrine and serotonin B. C. Motivation Hierachical Drive States of Motivations Love Pleasure Drive states are characterized by tension and discomfort due to a physiological need followed by relief when the need is satisfied. Physiological Needs • Temperature regulation involves integration of autonomic, endocrine, and skeletomotor responses • Feeding behavior Is regulated by a variety of mechanisms • Drinking is regulated by tissue osmolality and vascular volume Recombinant human leptin 0.01-0.04 mg/kg/day, 18 months Noningestive behavior of all three patients was consistently observed to change from very docile and infantile to assertive and adult-like, within 2 weeks of the onset of leptin treatment, before weight loss occurred. PNAS 2004 Motivational States Can Be Regulated by Factors Other Than Tissue Needs Experimental Self-Stimulation of the Brain Reward Pathway The Mesolimbic Dopaminergic Pathways Important for Reinforcement In the presence of the drugs animals self-stimulate with a lower-frequency current that was previously ineffective.