autonomic ne rvous system The autonomic ne rvous system The autonomic ne rvous system Pa rasympathetic Sympathetic

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1 Chapter 5: Bodily Changes and Emotion William James contended that an emotionally exciting fact provokes bodily responses, which in turn lead to the experience of emotion My thesis is that the bodily changes follow directly the perception of the exciting fact, and that our feeling of the same changes as they occur is the emotion That every emotion, from anger to sympathy to the rapturous delight of hearing a favorite musician, involves a distinct bodily reverberation detected by the autonomic nervous system and by neural signals from the workings of our muscles The autonomic nervous system Neural signals from the cortex communicate with the limbic system and the hypothalamus These brain regions send signals through clusters of neurons of the autonomic nervous system to the target organs, glands, muscles, and blood vessels These structures, in turn, send signals back via the autonomic nervous system to the hypothalamus, limbic system, and cortex The autonomic nervous system most general function is to maintain the internal condition of the body, to enable adaptive response to varying environmental events Parasympathetic branch: helps with the restorative processes, reducing heart rate and blood pressure and increasing digestive processes Sympathetic branch: increases heart rate, blood pressure, and cardiac output and shuts down digestive processes, to help the individual to engage in physically demanding actions The autonomic nervous system maintains the inner environment of the body, to enable the individual s adaptive response to varying external environmental events o It controls processes such as digestion, body fluids, blood flow, and temperature The system is also closely associated with various behaviors with direct relevance to emotion, including defensive behavior, sexual behavior, and aggression The system s two branches originate in different parts of the spinal cord and that are controlled by different neurotransmitters The parasympathetic and sympathetic branches The parasympathetic autonomic nervous system incorporates nerves that originate in two different parts of the spinal cord: the vagus nerve, at the top of the spinal cord, and in the sacral region near the bottom of the spinal cord o This system decreases heart rate and blood pressure o Essential to the sexual response o It stimulates the secretion of various fluids throughout the body, including those in the digestive glands, salivation, and tears The sympathetic system involves over a dozen different neural pathways originating at several sites on the spinal cord o Most typically acts in the opposite way from the parasympathetic system o It increases heart rate, blood pressure, and cardiac output o Shuts down digestive processes o May be part of certain emotional responses that involve goose-bumps o Also increases many processes that provide energy for the body

2 o Many have argued that this system helps prepare the body for fight or flight responses Two support for James s claims regarding autonomic specificity and emotion: o 1. There are over a dozen distinct autonomic pathways that activate different regions of the body. So different emotions could potentially be involved with distinct pathways in the autonomic nervous system o 2. One can imagine many different ways in which components of the autonomic system could combine, including heart rate, blood flow to the skin, sweating, production of tears, stomach activity, and breathing Cannon s critique of autonomic specificity Cannon proposed instead that bodily changes are produced by the brain, and that they are similar during different emotions such as anger and fear Proposed that quite different emotions involved exactly the same general activation of the sympathetic nervous system Arousal response includes release of the hormone adrenaline o The effects of this sympathetic-adrenal response are a shift of bodily resources to prepare for action, including fight, flight, and sexual behavior Cannon criticizes James s autonomic specificity thesis by 1) arguing that the responses of the autonomic nervous system (changes of heart rate, breathing, sweat responses, etc) are too diffuse and nonspecific to account for the distinct varieties of emotional experience o The specificity and nuance of different emotions was to be found not in the body, but in the brain 2) That autonomic responses are too slow to account for the rapidity with which we experience emotion, or move from one emotion to another o Cannon contended that the experience of emotion arises more quickly than autonomic activity 3) That the main actions of the autonomic nervous system, actually occur in a variety of other states, such as fevers, cold exposure, or asphyxia o e.g. love and fevers having the same autonomic patterning o James s hypothesized that each emotion is associated with a distinct autonomic pattern Questioned whether our sensitivity to change in the autonomic nervous system is refined enough to result in the many emotional states we experience Argued that for the most part we are insensitive to autonomic sensations o They are simply too inaccessible or dull to give rise to emotional experience The two-factor theory of emotion How people construe emotional situations as the source of different emotional experiences One important component of an emotional experience within this theory is undifferentiated physiological arousal Schachter and Singer assumed that a single type of general arousal is associated with very different emotions o e.g. injecting their participants with adrenaline and how their responses vary in terms of whether the experimenter s accomplice was euphoric or angry The theory added to the interest on appraisal

3 When physiological arousal or an anxiety state does not have an obvious source, people do tend to label and experience their arousal according to what is happening in the current situation Misattribution of arousal: how arousal from one source (e.g. difficulties at work) can be attributed to some other, salient source in the environment (tensions over housework at home) That arousal, sometimes purely physiological, and sometimes from certain emotions such as anxiety, can transfer to other situations and have effects on our emotional experience of the social world Evidence for autonomic specificity in emotion Ekman noticed that moving his facial muscles seemed to change how he felt e.g. when he furrowed the brow his heart rate seemed to increase and his blood pressure to rise Directed facial action task There were only two hypotheses inspired by Cannon about the non-specificity of emotionrelated changes in the autonomic nervous system o 1. All emotions involve elevated sympathetic response o 2. The negative emotions all involve increased sympathetic arousal, whereas positive emotions involve reduced arousal They found that four negative emotions differ on certain measures of autonomic activity, suggesting that a one-arousal-fits-all model of autonomic activity is inadequate The idea that once an emotion is activated, it is associated with some distinct physiological responses; and these distinctions may be universal The blush The autonomic response that differs from others Some nonhuman primates also show reddening in the face, perhaps as an appeasement gesture Darwin observed that the blush is associated with several states, including modesty, embarrassment, shyness, and shame Argued that the blush is the product of self-focused attention Mark Leary et al proposed a more specific cause for blushing: negative, self-focused attention o We don t blush when we receive attention from others, or when we think of what others think of us; rather, we blush when are the objects and the recipients of undesirable social attention (attention that is potentially damaging to our selfconcept) The experience of blushing often is associated with certain fears, most notably social anxiety Researchers have argued that these different patterns of correlations indicate that the autonomic controls of blushing and feeling fearful may involve distinct neural pathways and cortical regions Parasympathetic response and social connection Steven Porges s three stages in the evolution of the autonomic nervous system

4 o Dorsal vagal complex: present in all species Regulates digestive processes, and produces the immobilization response seen in many reptiles and fish when attacked by predators o The sympathetic nervous system: controls fight and flight behavior o Ventral vagal complex: controlled by the central cranial nerve (vagus nerve) Affects several behaviors critical to social interaction and attachment Also influences cardiac output in ways that allow the individual to rapidly adapt to changing social circumstances; and in ways that allow the individual to be calm around others Empirical consensus that vagal influences upon the parasympathetic nervous system may be associated with social engagement and altruistic emotions like love and compassion Emotional experience with reduced bodily input Tomkins argued that the experience of emotion closely tracks emotion-specific bodily responses Emotions when in the absence of bodily sensations was found to involve the decreases in sexual feelings, fear, and anger; most subjects reported an increase in feelings called sentimentality (Hohmann), feeling tearful and choked up on occasions such as partings How people experience emotions may depend on how they interpret them, on the extent to which they believe emotion to be affected by body sensations Action and emotion Feedback from actions might be particularly important in understanding bodily bases of emotion because different emotions are certainly associated with different kinds of action Nico Frijda has argued that action readiness supported by autonomic activity is the core of an emotion Emotions, for Frijda, are about preparing the individual for different courses of actin in response to events in the environment At the core of emotions are tendencies to approach goals, to soothe, to aggress, to submit, and so on Profiles of action readiness are at least as good in characterizing emotions as profiles of appraisal Appraisals were meaningfully related to states of action readiness Meaningful patterns emerge by looking at individual groups of emotions o e.g. positive emotions (pride, relief, enthusiasm) all show pleasant and selfagency as appraisals, and exuberant as the state of action readiness o Anger and rage involved unpleasant and other-agency as appraisals, and antagonistic action readiness Emotions are the processes that allow us to focus on any problem that has arisen, and to change course if necessary, by making ready a new course of action Eliciting emotion by bodily action Zajonc, Murphy, and Inglehart proposed that some facial expressions have emotional effects by constricting flow through blood vessels in the face

5 o In turn these constrictions affect blood flow through parts of the brain, which then produce temperature changes that are experienced as positive or negative o e.g. facial muscle actions that allow air to flow to the brain cool the brain, which is experienced as a positive emotion Other studies have also illustrated how moving emotion-relevant muscles induces an affective experience o e.g. making people raise their arms horizontally for three minutes, which induces pain and irritation, can make them act more aggressively toward others There is suggestive evidence that facial and bodily changes can cause or intensify emotions, though the intensity of these emotions remains low The somatic market hypothesis Somatic market hypothesis: for patients with damaged ventromedial frontal cortex, the deficits in emotions, planning, and a concern for others have a common cause Emotions are necessary because necessary because when we plan our lives, we rely on our emotions to guide our decision making; we do not even consider decisions that would be socially punishing Damasio proposes that it was this socioemotional guidance system that was affected in the brains of the original Phineas Gage and of the modern Phineas Gages he had studied The guidance system to him is the body itself: emotional events are experienced as bodily reactions, somatic markers These markers can be learned so that in thinking of possible decisions, any outcome of a kind that has previously been bad for you you experience as an unpleasant gut feeling Damage to the ventromedial frontal cortex means we will no longer have access to these somatic markers