Emotions Chapter 11 Biological Psychology James W. Kalat 12ed PDF

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Chapter 11Emotions and Autonomic Arousal“cognitive evaluations, subjective changes, autonomic and neural arousal, and impulses to action” (Plutchik, 1982)Emotional situations arouse the two branches of the autonomic nervous system—the sympathetic and the parasympathetic.Sympathetic nervous system st...

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Chapter 11 Emotions and Autonomic Arousal “cognitive evaluations, subjective changes, autonomic and neural arousal, and impulses to action” (Plutchik, 1982) Emotional situations arouse the two branches of the autonomic nervous system—the sympathetic and the parasympathetic. Sympathetic nervous system stimulates certain organs, such as the heart, while inhibiting others, such as the stomach and intestines. James-Lange theory - the autonomic arousal and skeletal actions come first. What you experience as an emotion is the label you give to your responses: You feel afraid because you run away, and you feel angry because you attack. Cannon-Bard theory of emotion (1927): objected that feedback from the viscera is neither necessary nor sufficient for emotion, that it does not distinguish one emotion from another, and that it is too slow to account for how fast we identify an event as happy, sad, or frightening.

In people with an uncommon condition called pure autonomic failure, output from the autonomic nervous system to the body fails, either completely or almost completely. Heart beat and other organ activities continue, but the nervous system no longer regulates them. Someone with this condition does not react to stressful experiences with changes in heart rate, blood pressure, or sweating. According to the James-Lange theory, we would expect such people to report no emotions. In fact, they report having the same emo- tions as anyone else People with damage to the right somatosensory cortex have normal autonomic responses to emotional music but report little subjective experience. People with damage to part of the prefrontal cortex have weak autonomic responses but normal subjective responses

If you had sudden intense arousal of the sympathetic nervous system without knowing the reason, you might experience it as an emotion. Such is the case with a panic attack, when people gasp for breath, worry that they are suffocating, and experience great anxiety Möbius syndrome cannot move their facial muscles to make a smile Traditionally, the limbic system—the forebrain areas surrounding the thalamus—has been regarded as critical for emotion No brain area seems critical for emotion in general without contributing to other aspects of behavior. What is the relevance of pure autonomic failure to the study of emotions? People with pure autonomic failure do not react to events with changes in heart rate or other autonomic functions. They report still having emotional experiences but they do not feel them as strongly. How did researchers get people to smile or frown without using those words? They got people to smile by telling them to hold a pen between their teeth. They got people to frown by attaching golf tees to their eyebrows and then telling them to keep the two tees touching each other. According to Lisa Barrett Feldman, why is it difficult to develop a scientific consensus about any theory of emotion? Emotion is a socially constructed category that people find useful, but it does not correspond to any category that exists in nature. Activity of the left hemisphere, especially its frontal and temporal lobes - behavioral activation system (BAS), marked by low to moderate autonomic arousal and a tendency to approach, which could characterize happiness or anger. Increased activity of the frontal and temporal lobes of the right hemisphere is associated with the behavioral inhibition system (BIS), which increases attention and arousal, inhibits action, and stimulates emotions such as fear and disgust On the average, people with greater activity in the frontal cortex of the left hemisphere tend to be happier, more outgoing, and more fun-loving. People with greater right-hemisphere activity tend to be socially withdrawn, less satisfied with life, and prone to unpleasant emotions. What evidence challenges the idea that we identify people’s emotions by their facial expressions? Given a photo of a spontaneous facial expression, people usually see more than one emotion and often don’t see the emotion described by the person whose face was shown. Also, in everyday life we identify someone’s emotion by a combination of cues, including posture, context, gestures, and tone of voice. The Functions of emotion

Emotional expressions help us communicate our needs to others and understand other people’s needs and probable actions. Also, emotions provide a useful guide when we need to make a quick decision. Brain scans show that contemplating the footbridge or lifeboat dilemma activates brain areas known to respond to emotions, including parts of the prefrontal cortex and cingulate gyrus. Damage to parts of the prefrontal cortex blunts people’s emotions in most regards. After damage to a particular part of the prefrontal cortex— the ventromedial prefrontal cortex —people show inconsistent preferences, as if they aren’t sure what they want or like If brain damage impairs someone’s emotions, what happens to the person’s decision making? After brain damage that impairs emotion, people make impulsive decisions, evidently because they do not quickly imagine how bad a poor decision might make them feel. 1. Most attempts to define emotion include several aspects including cognition, feelings, and action. 2. The sympathetic nervous system readies the body for emergency fight-or-flight activities. 3. According to the James-Lange theory, the feeling aspect of an emotion results from feedback from actions of the muscles and organs. 4. People who have impaired autonomic responses continue to report emotional experiences, although the feeling aspect is weaker than before. 5. Feedback from facial movements or other actions is not necessary for emotional experience, but it can strengthen emotional feelings. 6. The various components of an emotion do not always occur together. Also, apparently no emotion corresponds to activity in a single brain area. For these and other reasons, many psychologists regard emotion as an arbitrary category, in which case we cannot expect to find any scientific answer to the question of what emotion is. 7. We recognize other people’s emotions by many cues, including facial expression, body posture, context, and tone of voice. Naturally occurring expressions do not fit neatly into a few distinct categories. 8. Activation of the frontal and temporal areas of the left hemisphere is associated with approach and the behavioral activation system. The corresponding areas of the right hemisphere are associated with withdrawal, decreased activity, and the behavioral inhibition system. 9. Brain damage that impairs emotional feelings and responses also impairs decision making. One interpretation is that people decide badly because they do not quickly imagine their emotional reactions to possible consequences. 10. People with damage to the ventromedial prefrontal cortex show inconsistent preferences, as if they are unsure what they want or like. They also show little concern for other people. They apparently lack a normal sense of guilt. How do the functions of the sympathetic nervous system differ from those of the parasympathetic nervous system? The sympathetic system readies the body for emergency activities, and the parasympathetic activates digestive and other less urgent responses. What is the contribution of the sympathetic nervous system to emotions? Sympathetic nervous system arousal is neither necessary nor sufficient for an emotional experience but it contributes to the feeling aspect of an emotion.

Which of the following causes a panic attack? Intense, unexplained arousal of the sympathetic nervous system. When researchers looked for brain areas associated with particular emotions, what did they find? No brain area is responsible for one and only one emotion. What brain area is associated with the behavioral activation system and a tendency to approach? The left hemisphere When people consider a moral dilemma such as whether to push someone off a bridge to save five other people, which of the following correlates with a stronger tendency to agree to push the person? Weaker autonomic arousal

Emotion is embodied: What you are doing affects how you feel. Effects of Hormones If we compare people of the same age, those with higher testosterone levels tend on average to be more aggressive. Researchers have documented that tendency for both men and women. An explanation for why testosterone generally has small effects is that testosterone facilitates aggression, whereas cortisol (associated with fear and anxiety) inhibits aggression. Therefore, aggression depends on the ratio of testosterone to cortisol, not testosterone alone. Serotonin also tends to inhibit violent impulses, so impulsive aggression is highest when testosterone levels are high, and both cortisol and serotonin are low. What is one reason why testosterone levels correlate only weakly with human aggression levels? Aggression depends on the ratio of testosterone to cortisol, not to testosterone alone. When neurons release serotonin, they reabsorb most of it and synthesize enough to replace the amount that washed away. Thus, the amount present in neurons remains fairly constant, but if we measure the serotonin metabolites in body fluids, we gauge the turnover, the amount that neurons released and replaced. Researchers measure serotonin turnover by the concentration of 5-hydroxyindoleacetic acid (5-HIAA), serotonin’s main metabolite, in the cerebrospinal fluid (CSF). Many studies have found low serotonin turnover in people with a history of violent behavior, including people convicted of arson and other violent crimes. If we want to know how much serotonin the brain has been releasing, what should we measure? We can measure the concentration of 5-HIAA, a serotonin metabolite, in the cerebrospinal fluid or other body fluids. The more 5-HIAA, the more serotonin has been released and presumably resynthesized. Given that monkeys with low serotonin turnover pick many fights and in most cases die young, what keeps natural selection from eliminating the genes for low serotonin turnover?

Although most monkeys with low serotonin turnover die young, many of the survivors achieve a dominant status that enables them to get more of the food and to reproduce more frequently. Monkeys with high serotonin turnover survive, but at the cost of accepting a low status. People with lower than average autonomic arousal tend, on average, to be more aggressive, probably because they react less strongly to fear of the consequences. After a neuron releases serotonin, dopamine, or norepinephrine, most of it returns to the neuron via reuptake. At that point the enzyme MAOA breaks down some of it, preventing possible accumulation of an excessive amount. People vary in their genes for MAOA, as some people have a less-active form of the gene. What relationship did Caspi et al. (2002) report between the enzyme MAOA and antisocial behavior? Overall, people with genes for high or low production of MAOA do not differ significantly in their probability of antisocial behavior. However, among those who suffered serious maltreatment during childhood, people with lower levels of the enzyme showed higher rates of antisocial behavior. Fear and Anxiety A sudden loud noise causes a newborn to arch the back, briefly extend the arms and legs, and cry. This reaction is called the Moro reflex. After infancy, a loud noise elicits the closely related startle reflex: Auditory information goes first to the cochlear nucleus in the medulla and from there directly to an area in the pons that commands tensing the muscles, especially the neck muscles. Your startle reflex is more vigorous if you are already tense. Variations in the startle reflex correlate well enough with anxiety that we can measure the startle reflex to measure anxiety. Investigators have determined that the amygdala is important for enhancing the startle reflex. Many cells in the amygdala, especially in the basolateral and central nuclei, get input from pain fibers as well as vision or hearing, so the circuitry is well suited to establishing conditioned fears By stimulating or damaging parts of laboratory animals’ amygdala, researchers have found that one path through the amygdala is responsible for fear of pain, another for fear of predators, and another for fear of aggressive members of your own species Amygdala and learned fears The central amygdala receives sensory input from the lateral and basolateral amygdala. It sends output to the central gray area of the midbrain, which relays information to a nucleus in the pons responsible for the startle reflex. Damage anywhere along the route from the amygdala to the pons interferes with learned fears that modify the startle reflex. Bed nucleus of the stria terminalis - The stria terminalis is a set of axons that connect this nucleus to the amygdala. Axons from this nucleus to the ventral tegmental area also control increases and decreases in anxiety.

What brain mechanism enables the startle reflex to be so fast? Loud noises activate a path from the cochlea to cells in the pons that trigger a tensing of neck muscles. How could a researcher use the startle reflex to determine whether some stimulus causes fear? Present the stimulus before giving a loud noise. If the stimulus increases the startle reflex beyond its usual level, then the stimulus produced fear. Klüver-Bucy syndrome - the effect of amygdala damage in monkeys, display less than the normal fear, impaired social behaviors. impaired social behaviors. Most infants with an “inhibited” temperament develop into shy, fearful children and then into shy adults who show an enhanced amygdala response to the sight of any unfamiliar face. Part of the variance in anxiety relates to genes controlling the serotonin transporter. People with genes for reduced serotonin reuptake tend to have increased responses to threat and increased attention to threatening stimuli, especially in social situations. As a result, they are more likely than others to have anxiety disorders and difficult social interactions. Those with the greatest amygdala response at the start reported the greatest amount of combat stress. An effective way to cope with anxiety is reappraisal—re- interpreting a situation as less threatening. Reappraisal and other methods of suppressing anxiety depend on top-down influences from the prefrontal cortex to inhibit activity in the amygdala. People with depression or severe anxiety show below-average activity in the prefrontal cortex while viewing something frightening, and techniques that help people reduce their anxiety tend to increase activity in the prefrontal cortex. What evidence indicates that amygdala activity corresponds to the effort needed for interpreting emotional information? The amygdala responds more strongly to a fearful face directed at the viewer, rather than a similar face looking to the side. People usually find it easier to understand a fearful face looking to the side. What can we predict about someone if we know the strength of that person’s amygdala responses to upsetting pictures or loud noises? People with a highly reactive amygdala are likely to report many negative emotional experiences during a day, to show strong responses to stressful experiences, and to favor strong reliance on military and police power. People with the rare genetic disorder Urbach-Wiethe disease accumulate calcium in the amygdala until it wastes away. Thus they have extensive damage to the amygdala without much damage to surrounding structures. Like the monkeys with Klüver-Bucy syndrome, they are impaired at processing emotional information and learning what to fear. Why do people with amygdala damage have trouble recognizing expressions of fear? They focus their vision on the nose and mouth. Expressions of fear depend almost entirely on the eyes Anxiety disorders In generalized anxiety disorder, phobia, and panic disorder, the major symptom is increased anxiety.

Panic disorder is characterized by frequent periods of anxi- ety and occasional attacks of rapid breathing, increased heart rate, sweating, and trembling—that is, extreme arousal of the sympathetic nervous system. genetic predisposition, although no single gene has been identified. The research so far links panic disorder to some abnormalities in the hypothalamus, and not necessarily the amygdala. Panic disorder is associated with decreased activity of the neurotransmitter GABA and increased levels of orexin. Orexin is associated with maintaining wakefulness and activity. Drugs that block orexin receptors block panic responses. Post-traumatic stress disorder (PTSD), marked by frequent distressing recollections (flashbacks) and nightmares about the traumatic event, avoidance of reminders of it, and vigorous reactions to noises and other stimuli. Most PTSD victims have a smaller than average hippocampus. What evidence indicates that a smaller than average hippocampus makes people more vulnerable to PTSD? On the average, PTSD victims have a smaller than average hippocampus. For those who have a monozygotic twin, the twin also has a smaller than average hippocampus, even if he or she does not have PTSD. Relief from Anxiety A variety of studies indicate that the transmitters orexin and CCK (cholecystokinin) increase anxiety by their actions in the amygdala and hippocampus. Many drugs are available to increase activity of the transmitter GABA, which inhibits anxiety. The most common anxiolytic (anti-anxiety) drugs are the benzodiazepines, such as diazepam (trade name Valium), chlordiazepoxide (Librium), and alprazolam (Xanax). Benzodiazepines bind to the GABAA receptor, which includes a site that binds GABA as well as sites that modify the sensitivity of the GABA site. A benzodiazepine molecule attaches, it neither opens nor closes the chloride channel but twists the receptor so that the GABA binds more easily. • → Benzodiazepines thus facilitate the effects of GABA Benzodiazepines exert their anti-anxiety effects in the amygdala, hypothalamus, midbrain, and several other areas. Benzodiazepines produce a variety of additional effects: addiction (in long-term), induce sleepiness, block epileptic convulsions, and impair memory + alcohol also promotes the flow of chloride ions Alcohol alters brain activity in several ways, but the effects on GABA receptors are responsible for the anti-anxiety and intoxicating effects. Alcohol promotes the flow of chloride ions through the GABAA receptor complex by binding strongly at a special site found on only certain GABAA receptors. What would be the effect of benzodiazepines on someone who had no GABA? Benzodiazepines facilitate the effects of GABA, so a person without GABA would have no response to benzodiazepines.

An effective approach, known as systematic desensitization, is to expose you gradually to your feared object, in hopes of extinction (in the classical- conditioning sense). It is easier to extinguish a learned response immediately after origi- nal learning than it is later. After time has passed, the learn- ing becomes stronger. Psychologists say it has consolidated. If you have a traumatic experience, no one is there to extinguish the learning in the next few minutes. However, a consolidated memory is not solid forever. A memory reawak- ened by a reminder becomes labile—that is, changeable or vulnerable. If a similar experience follows the reminder, the memory is reconsolidated—that is, strengthened again. Dur- ing the time when reconsolidation might occur, a well-timed extinction experience can substantially weaken the memory. The drug propanolol interferes with protein synthesis at certain synapses in the amygdala. Why is extinction more effective a few minutes after a brief reminder of the original learning? The reminder brings the representation of the learning into a labile state from which it can be reconsolidated or extinguished. Summary An experience that gradually provokes an attack leaves an individual more ready than usual to attack again. Differences in testosterone levels correlate weakly with variations in aggressive behavior. Aggressive behavior depends on a combination of chemicals, as testosterone increases the probability and cortisol decreases it. Low serotonin turnover is associated with an in...