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Emotion and the nervous system Immunity, and health Biological origins of emotion Garrett: Brain & Behavior 4e Emotion and Health Chapter 8 1 Emotion and the Nervous System Figure 8.1: Sympathetic & Parasympathetic systems both involved. • Emotion: defined • Sympathetic nervous system (Fight or Flight) • Stimulates adrenals to release hormones, particularly cortisol. • Parasympathetic nervous system (Relaxation) Garrett: Brain & Behavior 4e • Reduces activity, conserves and restores energy 2 SOURCE: Text Emotion and the Nervous System Autonomic and Muscular Involvement in Emotion • The Role of Feedback from the Body • James-Lange Theory • Cognitive Theory (Schacter & Singer) • Cognitive appraisal determines the emotion • Physiological arousal determines the intensity • Neither theory has won out, but they have led to insights. Garrett: Brain & Behavior 4e • Situation causes a physiological reaction, which is then interpreted as an emotion 3 Emotion and the Nervous System • In response to ‘stress’, the adrenal glands release stress hormones. • These include epinephrine, norepinephrine, and cortisol • A network of structures around the upper brain stem are also involved: • Areas implicated or activated by emotions include the Anterior Cingulate Cortex, the Hypothalamus, Septal Nuclei, the *Amygdala, the Insular Cortex, and Basal Ganglia • Widely scattered brain activity also occurs as a result of emotional stimulation Source: © Don Francis/Mardan Photography Garrett: Brain & Behavior 4e The Emotional Brain Figure 8.4: The Limbic System 4 Emotion and the Nervous System Garrett: Brain & Behavior 4e The Emotional Brain Figure 8.5: Location of the Amygdala, Insula, and Basal Ganglia 5 SOURCE: Photo courtesy of Dana Copeland. Emotion and the Nervous System • Paul Ekman showed that ‘posed’ expressions could produce the intended emotion, and a distinct pattern of physiological arousal. • Women with Botox paralysis of facial muscles. • Reported less negative moods • Produced less amygdala activity when imitating angry expressions • Gum chewing can impair detecting emotions in pictures Garrett: Brain & Behavior 4e Autonomic and Muscular Involvement in Emotion. Figure 8.3: Disabling Corrugator Muscle Reduces Amygdala Response to Simulated Anger 6 SOURCE: Adapted from “The Link Between Facial Feedback and Neural Activity Within Central Circuitries of Emotion—New Insights from Botulinum Toxin-Induced Denervation of Frown Muscles,” by A. Hennenlotter, C. Dresel, F. Castrop, A. O. Ceballos Baumann, A. M. Woschläger, and B. Haslinger, 2009, Cerebral Cortex, 19, 537–542. Used with permission of Oxford University Press. Emotion and the Nervous System Autonomic and Muscular Involvement in Emotion • Mirror neurons • This may be why observing emotions in others activates our own brain’s emotional areas. • The degree of activation is related to the person’s score on a measure of empathy. • Autistic children, with delayed mimicry, also have low empathy Garrett: Brain & Behavior 4e • Respond while observing a specific act • Also respond performing the same act 7 Emotion and the Nervous System Garrett: Brain & Behavior 4e The Emotional Brain Figure 8.6: Size Differences in the Anterior Cingulate Gyrus 8 SOURCE: From “Anatomical Variability of the Anterior Cingulated Gyrus and Basic Dimensions of Human Personality,” by J. Pujl et al., NeuroImage, 15, 847–855, fig. 1, p. 848. © 2002 with permission from Elsevier, Ltd. Emotion and the Nervous System The Prefrontal Cortex. • Bechara: Skin-conductance response (SCR) decreases correlated to inability to understand consequences of risky behavior • Abnormalities in the prefrontal cortex may be involved in disorders like depression and schizophrenia • When disconnected (lobotomy) people’s capacity to make rational judgments is compromised Garrett: Brain & Behavior 4e • Is involved in the control of risky or thrill seeking behavior • Damage to this area early vs. late in life 9 Emotion and the Nervous System Garrett: Brain & Behavior 4e The Prefrontal Cortex. Figure 8.9: Comparison of Gambling Task Behavior in Controls and Patients with Damage to Prefrontal Cortex 10 SOURCE: Text Emotion and the Nervous System The Amygdala. Figure 8.10: Activity in the Right Amygdala While Viewing Facial Expressions of Fear Garrett: Brain & Behavior 4e Fear versus anxiety • Damage to the amygdala does not reduce bodily induced panic (carbon dioxide exposure) • Anxiety-reducing drugs 11 SOURCE: Reprinted with permission from “Serotonin Transporter Genetic Variation and the Response of the Human Amygdala,” by Hariri et al., Science, 297, pp. 400–403. Copyright 2002. Reprinted by permission of AAAS. Emotion and the Nervous System Garrett: Brain & Behavior 4e The Amygdala. Figure 8.11: SM’s Brain Compared to a Normal Brain 12 SOURCE: Iowa Neurological Patient Registry/University of Iowa Emotion and the Nervous System Hemispheric Specialization in Emotion • Left frontal - positive emotions • Damage- more anxiety and sadness about life • Greater autonomic responses to emotional stimuli (facial expressions, emotional scenes) • Damage • Unperturbed or euphoric even when bad things happen • Patients with right-hemisphere damage have trouble recognizing emotion in facial expressions and tone of voice. • They also have problems producing emotion in speech. Garrett: Brain & Behavior 4e • Right frontal- negative emotion. 13 Stress, Immunity, and Health Stress as an Adaptive Response Figure 8.12: The Hypothalamus-Pituitary-Adrenal (HPA) Axis • Sympathetic n.s. • Hypothalamic control. • Increases heart rate, blood flow, and respiration rate • Hypothalamic-pituitary-adrenal (HPA) axis • Epinephrine & norepinephrine for short term stressors • Cortisol for prolonged stress • Immune system fights off any invaders, initially. Garrett: Brain & Behavior 4e Activates 14 SOURCE: Text Stress, Immunity, and Health • Stress may be an environmental condition, or an internal condition in response to a demanding event. • Stress is adaptive under most circumstances. • Brief stress increases immune system activity Table 8.1 Macrophages *Leucocytes T Cells B Cells Ingest invaders, Multiply and attack Make antibodies, display antigens, invaders. which destroy which attract T cells intruders. Natural Killer Cells Attack cells containing viruses, certain kinds of tumor cells. Microglia Ingest invaders, display antigens to attract T cells in brain, spinal cord Garrett: Brain & Behavior 4e Stress as an Adaptive Response 15 Stress, Immunity, and Health Negative Effects of Stress. Figure 8.14: Relationship Between Stress and Vulnerability to Colds. Figure 8.15: Increase in Cardiac Deaths on the Day of an Earthquake • Chronic stress impairs immunity and health, particularly in the cardiovascular system. Garrett: Brain & Behavior 4e • Increased colds, blood pressure, sudden cardiac death 16 SOURCES: (LEFT) Adapted with permission from “Psychological Stress and Susceptibility To the Common Cold,” by S Cohen, A. D. Tyrrell, and A. P. Smith, New England Journal of Medicine, 325, pp. 606–612. © 1991 Massachusetts Medical Society. All rights reserved. (RIGHT) Reprinted with permission from J. Leor, W. K. Poole, & R. A. Kloner, “Sudden Cardiac Death Triggered by an Earthquake.” New England Journal of Medicine, 334, pp. 413–419. © 1996 Massachusetts Medical Society. All rights reserved. Stress, Immunity, and Health Negative Effects of Stress Figure 8.16: Hippocampal Damage in a Stressed Monkey • Negative changes due to chronic stress • Cortisol-related damage to hippocampus, gray matter • Altered sleep cycles due to stress also cause illness • May trigger autoimmune diseases like Multiple Sclerosis (demylenating) Garrett: Brain & Behavior 4e • *Elevated levels, or Increased receptor sensitivity to glucocorticoids • *Example: Citizens near 9/11 attacks had reduced cortisol levels 17 SOURCE: From “Hippocampal Damage Associated With Prolonged and Fatal Stress in Primates,” by H. Uno, R. Tarara, J. G. Else, M. A. Suleman, and R. M. Sapolsky, 1999, Journal of Neuroscience, 9, 1705–1711. Stress, Immunity, and Health Social, Personality, and Genetic Factors Figure 8.16: Post-vaccine antibody levels in relation to hemispheric activity • NPY- high functioning versions have better stress reactions (Ch 6) • OXTR- less stress seen in individuals who make more oxytocin (Ch 7) Garrett: Brain & Behavior 4e • Social support correlated to improved health outcomes • Introverted, stressful personalities make less antibodies • Genes correlated with 32% of workplace stress 18 SOURCE: From “Affective Style and in vivo Immune Response,” by M. A. Rosenkranz et al., PNAS, 100, pp. 11148–11152. © 2003. Stress, Immunity, and Health • Pain is a health problem (85% of doctor visits are associated with pain relief issues) , but it is also adaptive • Congenital insensitivity to pain • The effect of pain depends on how it is viewed, as seen in • Childbirth • Soldiers • Ritualized torture Garrett: Brain & Behavior 4e Pain as an Adaptive Emotion Figure 8.18: Voluntary Ritualized Torture in Religious Practice 19 Stress, Immunity, and Health • Anterior cingulate cortex- involved in reactions to emotional pain, as well as the anticipation of pain. • Independent of somatosensory cortex • Pain insensitivity disorders and lobotomy patients can feel emotional pain. Garrett: Brain & Behavior 4e Pain as an Adaptive Emotion. See Figure 8.19: Painful heat effects on the somatosensory area (left of center) and anterior cingulate (midline) 20 Biological Origins of Aggression • Aggression: Behavior that is intended to harm. • Two forms in animals: • Predatory: attack and kill prey... emotionless • Is associated with reduced serotonin activity. • Affective: characterized by emotional arousal. • Offensive aggression: unprovoked attack on another animal. • Defensive aggression: response to threat, motivated by fear. Garrett: Brain & Behavior 4e Definition and Types of Aggression 21 Biological Origins of Aggression Hormones and Aggression Figure 8.20: Testosterone Levels of Men Convicted of Various Crimes • Low serotonin, estrogen/progesterone • High testosterone and violence • But aggression does not change with testosterone manipulation Garrett: Brain & Behavior 4e • Hormones and offensive aggression (like violent alcolohics) 22 SOURCE: Based on J. M. Dabbs et al. (1995) Biological Roots of Aggression The Brain’s Role in Aggression Figure 8.21: Brain Circuits for Defensive and Predatory Aggression in the Cat • Cats: defensive and predatory aggression pathways • Humans: • *‘Fit of Rage’ murderers have reduced activity levels in the prefrontal cortex. • Amygdala lesions reduce aggression in 33%-100% of patients Garrett: Brain & Behavior 4e • Tumors in the hypothalamus or septal area • Amygdala: Seizure activity, and higher activity in murderers 23 SOURCE: Based on A. Siegel et al. (1999). Biological Origins of Aggression Reactive & Proactive Aggression Involve Different Patterns of Brain Function • Antisocial personality disorder • Impaired self-functioning (ego-centric behaviors) • Impaired interpersonal functioning (lack of empathy, intimacy) • Pathological personality traits • Antagonism • Disinhibition • Physiological Mechanisms • Murderers: 22% less prefrontal gray matter Garrett: Brain & Behavior 4e • Diagnostic Criteria (DSM-5) • Neurocriminology 24 SOURCE: American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). Arlington, VA: American Psychiatric Publishing. Biological Origins of Aggression Neurotransmitters and Aggression. Figure 8.22: Prefrontal Dopamine and Serotonin in Rats During and Following Fights • Dopamine: High in prefrontal cortex, accumbens and in aggressive psychiatric patients • GABA: Inhibits aggression and impulsivity • Serotonin: Low activity and aggression, impairs prefrontal cortex Garrett: Brain & Behavior 4e • Testosterone: high levels (with low serotonin) • Alcohol: depletes serotonin, triggering craving 25 SOURCE: Adapted from Figure 2b from “Aggressive Behavior, Increased Accumbal Dopamine, and Decreased Cortical Serotonin in Rats,” by Annemoon M. M. van Erp and Klaus A. Miczek, Journal of Neuroscience, 15, pp. 9320-9325. Copyright 2000. Biological Origins of Aggression Heredity and Environment. Figure 8.22: Genetic Influence on Violent Behavior in Victims of Childhood Maltreatment. • Genetics (50%) • Genes influencing dopamine, GABA, serotonin systems • Childhood neglect or maltreatment • Epigenetic effect on people with certain alleles that have poor childhoods • MAOA-L allele • HTR2B serotonin receptor • SLC6A4 gene SOURCE: Based on data from “Role of Genotype in the Cycle of Violence in Maltreated Children,” by A. Caspi et al., 2002, Science, 292, p. 852. Garrett: Brain & Behavior 4e • Environment (50%) 26 Biological Origins of Aggression Neurocriminology, Responsibility, and the Law • Neurocriminology • Donta Page (1999)- released early from prison for robbery despite high risk for violence due to family history and personality traits, then committed murder. • Now: • Sandy Hook shooting and the Avielle Foundation httphttp://www.aviellefoundation.org/our-objectives/brain-health2http://www.aviellefoundation.org/our-objectives/brain-health2/ Garrett: Brain & Behavior 4e • Genes and biology being considered as predictors of behavior • Before: 27