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James L Mcgaugh - One of the best experts on this subject based on the ideXlab platform.
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Emotional Arousal regulation of memory consolidation
Current Opinion in Behavioral Sciences, 2018Co-Authors: James L McgaughAbstract:Recent findings provide increased understanding of how Emotional Arousal creates lasting memories. The findings are consistent with those of prior studies suggesting that the enhancement assessed in human subjects results from activation of adrenergic and glucocorticoid stress hormones. Additionally, fMRI imaging findings indicate that the enhancement is influenced by activation of the amygdala and its subsequent influences on other brain systems. Findings of recent animal studies using posttraining noradrenergic or optogenetic activation of the amygdala provide extensive evidence that the basolateral amygdala modulates memory consolidation by influencing neuroplasticity in downstream brain systems involved in processing different forms of memory. Activation of these systems helps to insure that Emotionally significant experiences are well remembered.
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glucocorticoid enhancement of memory requires Arousal induced noradrenergic activation in the basolateral amygdala
Proceedings of the National Academy of Sciences of the United States of America, 2006Co-Authors: Benno Roozendaal, Shoki Okuda, Eddy A Van Der Zee, James L McgaughAbstract:Considerable evidence indicates that glucocorticoid hormones enhance the consolidation of long-term memories for Emotionally arousing experiences but not that for less arousing or neutral information. However, previous studies have not determined the basis of such Arousal-induced selectivity. Here we report the finding that endogenous noradrenergic activation of the basolateral complex of the amygdala (BLA) induced by Emotional Arousal is essential in enabling glucocorticoid memory enhancement. Corticosterone administered immediately after object recognition training enhanced 24-h memory of naive male rats but not that of rats previously habituated to the training context in order to reduce novelty-induced Emotional Arousal. The β-adrenoceptor antagonist propranolol administered either systemically or into the BLA blocked the corticosterone-induced memory enhancement. Further, in habituated rats, corticosterone activated BLA neurons, as assessed by phosphorylated cAMP response element binding (pCREB) immunoreactivity levels, and enhanced memory only when norepinephrine release was stimulated by administration of the α2-adrenoceptor antagonist yohimbine. These findings strongly suggest that synergistic actions of glucocorticoids and Emotional Arousal-induced noradrenergic activation of the BLA constitute a neural mechanism by which glucocorticoids may selectively enhance memory consolidation for Emotionally arousing experiences.
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Emotional Arousal and enhanced amygdala activity new evidence for the old perseveration consolidation hypothesis
Learning & Memory, 2005Co-Authors: James L McgaughAbstract:Just a little over a century has passed since Muller and Pilzecker (1900) proposed the “perseveration-consolidation” hypothesis suggesting that neural activity initiated by newly learned information perseverates for a while and that such perseveration is critical for consolidating memory. Although memory consolidation is currently the focus of considerable research investigating the molecular mechanisms responsible for converting new memories into lasting memories and the brain regions essential for such conversion, “perseveration” has been dropped from the hyphenated hypothesis and has not remained an explicit focus of research and theory concerning memory consolidation (McGaugh 1999, 2000). The essential experimental evidence supporting the memory consolidation hypothesis is that the memoryinfluencing effectiveness (i.e., impairment or enhancement) of treatments administered after training decreases as the training–treatment interval is increased. Such findings do not require an assumption that the treatments act by altering perseverating neural activity, as many kinds of neural alterations might be (and probably are) responsible for time-dependent effects of post-training treatments. Although it is now generally accepted that memories are formed by the action of processes occurring over time after learning, it is also generally assumed that such processes may involve many sequential cellular events as well as sequential functioning of different brain systems (McClelland et al. 1995; Squire and Alvarez 1995; Izquierdo et al. 2004). The findings of the study by Pelletier et al. (2005) in this issue of Learning & Memory, provide compelling evidence suggesting that it may now be appropriate to restore “perseveration-” to the consolidation hypothesis. Using extracellular multiple microelectrode arrays, Pelletier and colleagues recorded the activity of neurons in the basolateral amygdala (BLA) of cats before and after a mild footshock administered for inhibitory avoidance training. The firing rate of the neurons, as well as the synchrony of the firing, increased significantly after the footshock, peaked at over half an hour later and did not return to baseline until over 2 h after the footshock. This general pattern of increased postfootshock activity was observed in approximately half of the BLA neurons that were recorded and was more prominent during slow-wave sleep than during wakefulness. Interestingly, the activity of some neurons peaked shortly after the footshock, whereas the activity of most cells peaked ∼40 min after the footshock. As Pelletier et al. (2005) note, this evidence of long-lasting (i.e., perseverating) increased firing of BLA neurons induced by footshock training fits well with the extensive evidence that the BLA is critically involved in modulating the consolidation of Emotionally arousing experiences (McGaugh 1990, 2004; Pare 2003). It is well established that adrenal stress hormones released by Emotionally arousing experiences modulate memory consolidation. Post-training administration of epinephrine or corticosterone produces dose-dependent and time-dependent enhancement of retention of a wide variety of training tasks, including inhibitory avoidance (McGaugh and Roozendaal 2002). These adrenergic and glucocorticoid treatments are ineffective in influencing memory when administered several hours after training. Importantly, in relation to the findings of Pelletier et al. (2005), adrenergic and glucocorticoid effects on memory consolidation are mediated by actions involving the BLA. Selective lesions of the BLA or adrenoceptor antagonists infused into the BLA block the memory-modulating effects of systemically administered adrenal stress hormones, and infusions of adrenoceptor agonists (e.g., norepinephrine) and glucocorticoid receptor agonists administered selectively into the BLA immediately after training produce dose-dependent enhancement of memory consolidation (McGaugh and Roozendaal 2002). Systemically administered adrenal stress hormones also increase the release of norepinephrine (NE) in the amygdala (Williams et al. 1998; McIntyre et al. 2004). Additionally, in rats given inhibitory avoidance training, NE levels in the amygdala increased immediately after the training and did not decline to baseline level for several hours. NE levels assessed within 90 min after training correlated highly with subsequent retention performance (McIntyre et al. 2002). Such findings support the general hypothesis that the adrenal stress hormones released by training-induced Emotional Arousal enhance memory consolidation by increasing both the amount and duration of noradrenergic activation within the amygdala (McGaugh and Roozendaal 2002). As Pelletier et al. (2005) note, the duration of increased BLA electrophysiological activity seen after inhibitory avoidance training fits well with the evidence from experiments investigating the effects of stress hormones and training-induced Emotional Arousal on NE release and memory (Pare 2003). Thus, it is tempting to suggest that the Emotional Arousal-induced increase in BLA noradrenergic activity and neuronal activity may be causally related. The increase in NE activity may directly affect neuronal firing of GABAergic local-circuit cells as well as projection cells within the BLA. Although it is also possible that the BLA neuronal firing might increase NE release by feedback to presynaptic adrenergic receptors or to brain stem noradrenergic sources (locus coeruleus and/or nucleus of the solitary tract), this seems unlikely, because NE levels increase quickly and peak within 15– 30 min after inhibitory avoidance training, whereas the peak of the increase in BLA firing reported by Pelletier et al. (2005) occurred later than that in most cells recorded. However, as the activity of a minority of neurons peaked within seconds after the footshock training, the possibility that such early neuronal acE-mail jlmcgaug@uci.edu; fax (949) 824-2952. Article and publication are at http://www.learnmem.org/cgi/doi/10.1101/ lm.93405.
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glucocorticoid effects on object recognition memory require training associated Emotional Arousal
Proceedings of the National Academy of Sciences of the United States of America, 2004Co-Authors: Shoki Okuda, Benno Roozendaal, James L McgaughAbstract:Considerable evidence implicates glucocorticoid hormones in the regulation of memory consolidation and memory retrieval. The present experiments investigated whether the influence of these hormones on memory depends on the level of Emotional Arousal induced by the training experience. We investigated this issue in male Sprague–Dawley rats by examining the effects of immediate posttraining systemic injections of the glucocorticoid corticosterone on object recognition memory under two conditions that differed in their training-associated Emotional Arousal. In rats that were not previously habituated to the experimental context, corticosterone (0.3, 1.0, or 3.0 mg/kg, s.c.) administered immediately after a 3-min training trial enhanced 24-hr retention performance in an inverted-U shaped dose–response relationship. In contrast, corticosterone did not affect 24-hr retention of rats that received extensive prior habituation to the experimental context and, thus, had decreased novelty-induced Emotional Arousal during training. Additionally, immediate posttraining administration of corticosterone to nonhabituated rats, in doses that enhanced 24-hr retention, impaired object recognition performance at a 1-hr retention interval whereas corticosterone administered after training to well-habituated rats did not impair 1-hr retention. Thus, the present findings suggest that training-induced Emotional Arousal may be essential for glucocorticoid effects on object recognition memory.
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a novel demonstration of enhanced memory associated with Emotional Arousal
Consciousness and Cognition, 1995Co-Authors: Larry Cahill, James L McgaughAbstract:Abstract The relationship between Emotional Arousal and long-term memory is addressed in two experiments in which subjects viewed either a relatively Emotionally neutral short story (presented as a brief slide show) or a closely matched but more Emotionally arousing story and were tested for retention of the story 2 weeks later. Experiment 1 provides essential replication of the results of Heuer and Reisberg (1990) and illustrates the common interpretive problem posed by the use of different stimuli (slides) in the neutral versus Emotional stories. In Experiment 2, identical slides (and sequence) were used in both the neutral and Arousal stores. Two different stories were created by varying the narration that accompanied each slide. In both experiments, subjects who viewed the Arousal story both experienced a greater Emotional reaction to the story than did the subjects who viewed the neutral story, and subsequently exhibited enhanced memory for the story. Subjects in Experiment 2 who viewed the Arousal story also recalled more slides than did the subjects who viewed the neutral story. This effect was greatest for story phase 2, the phase in which the Emotional slide narration occurred. Because this enhanced retention of the story slides cannot be explained by any differences in the slides themselves, the results provide new evidence to support the contention that Emotional Arousal influences long-term memory in normal human subjects.
Kim Fromme - One of the best experts on this subject based on the ideXlab platform.
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the effects of alcohol emotion regulation and Emotional Arousal on the dating aggression intentions of men and women
Psychology of Addictive Behaviors, 2014Co-Authors: Cynthia A Stappenbeck, Kim FrommeAbstract:Verbal and physical dating aggression is prevalent among college-aged men and women, especially a pattern of mutual aggression in which both partners engage in aggression. Alcohol intoxication and anger Arousal have been implicated in the occurrence of aggression, and the ability to regulate one's emotions may interact with both alcohol intoxication and Emotional Arousal to predict dating aggression. The current study is the first known experimental investigation to examine the effects of alcohol intoxication, alcohol expectancies, emotion regulation, and Emotional Arousal on dating aggression. Participants were randomized to receive alcohol (n = 48), placebo (n = 48), or no alcohol (n = 48). Intoxicated men and women expressed more verbal and physical aggression intentions than those in the no-alcohol condition, and individuals in the placebo condition did not significantly differ from those in the alcohol and no-alcohol conditions. These results suggest that the pharmacological effects of alcohol were important to the occurrence of dating aggression, whereas the effects of expectancy are less clear. Among those less able to engage in cognitive reappraisal, individuals who consumed or believed they consumed alcohol expressed more verbal and physical aggression intentions than those who received no alcohol. Those with higher Arousal who were better able to suppress their emotions expressed fewer verbal and physical aggression intentions than those with lower Arousal. In addition to reducing alcohol consumption, interventions for dating aggression might incorporate emotion regulation skills, with a focus on understanding the circumstances in which cognitive reappraisal and emotion suppression are relatively more effective. (PsycINFO Database Record (c) 2013 APA, all rights reserved). Language: en
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the effects of alcohol emotion regulation and Emotional Arousal on the dating aggression intentions of men and women
Psychology of Addictive Behaviors, 2014Co-Authors: Cynthia A Stappenbeck, Kim FrommeAbstract:Verbal and physical dating aggression is prevalent among college-aged men and women, especially a pattern of mutual aggression in which both partners engage in aggression. Alcohol intoxication and anger Arousal have been implicated in the occurrence of aggression, and the ability to regulate one's emotions may interact with both alcohol intoxication and Emotional Arousal to predict dating aggression. The current study is the first known experimental investigation to examine the effects of alcohol intoxication, alcohol expectancies, emotion regulation, and Emotional Arousal on dating aggression. Participants were randomized to receive alcohol (n = 48), placebo (n = 48), or no alcohol (n = 48). Intoxicated men and women expressed more verbal and physical aggression intentions than those in the no-alcohol condition, and individuals in the placebo condition did not significantly differ from those in the alcohol and no-alcohol conditions. These results suggest that the pharmacological effects of alcohol were important to the occurrence of dating aggression, whereas the effects of expectancy are less clear. Among those less able to engage in cognitive reappraisal, individuals who consumed or believed they consumed alcohol expressed more verbal and physical aggression intentions than those who received no alcohol. Those with higher Arousal who were better able to suppress their emotions expressed fewer verbal and physical aggression intentions than those with lower Arousal. In addition to reducing alcohol consumption, interventions for dating aggression might incorporate emotion regulation skills, with a focus on understanding the circumstances in which cognitive reappraisal and emotion suppression are relatively more effective. (PsycINFO Database Record (c) 2014 APA, all rights reserved).
Cynthia A Stappenbeck - One of the best experts on this subject based on the ideXlab platform.
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the effects of alcohol emotion regulation and Emotional Arousal on the dating aggression intentions of men and women
Psychology of Addictive Behaviors, 2014Co-Authors: Cynthia A Stappenbeck, Kim FrommeAbstract:Verbal and physical dating aggression is prevalent among college-aged men and women, especially a pattern of mutual aggression in which both partners engage in aggression. Alcohol intoxication and anger Arousal have been implicated in the occurrence of aggression, and the ability to regulate one's emotions may interact with both alcohol intoxication and Emotional Arousal to predict dating aggression. The current study is the first known experimental investigation to examine the effects of alcohol intoxication, alcohol expectancies, emotion regulation, and Emotional Arousal on dating aggression. Participants were randomized to receive alcohol (n = 48), placebo (n = 48), or no alcohol (n = 48). Intoxicated men and women expressed more verbal and physical aggression intentions than those in the no-alcohol condition, and individuals in the placebo condition did not significantly differ from those in the alcohol and no-alcohol conditions. These results suggest that the pharmacological effects of alcohol were important to the occurrence of dating aggression, whereas the effects of expectancy are less clear. Among those less able to engage in cognitive reappraisal, individuals who consumed or believed they consumed alcohol expressed more verbal and physical aggression intentions than those who received no alcohol. Those with higher Arousal who were better able to suppress their emotions expressed fewer verbal and physical aggression intentions than those with lower Arousal. In addition to reducing alcohol consumption, interventions for dating aggression might incorporate emotion regulation skills, with a focus on understanding the circumstances in which cognitive reappraisal and emotion suppression are relatively more effective. (PsycINFO Database Record (c) 2013 APA, all rights reserved). Language: en
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the effects of alcohol emotion regulation and Emotional Arousal on the dating aggression intentions of men and women
Psychology of Addictive Behaviors, 2014Co-Authors: Cynthia A Stappenbeck, Kim FrommeAbstract:Verbal and physical dating aggression is prevalent among college-aged men and women, especially a pattern of mutual aggression in which both partners engage in aggression. Alcohol intoxication and anger Arousal have been implicated in the occurrence of aggression, and the ability to regulate one's emotions may interact with both alcohol intoxication and Emotional Arousal to predict dating aggression. The current study is the first known experimental investigation to examine the effects of alcohol intoxication, alcohol expectancies, emotion regulation, and Emotional Arousal on dating aggression. Participants were randomized to receive alcohol (n = 48), placebo (n = 48), or no alcohol (n = 48). Intoxicated men and women expressed more verbal and physical aggression intentions than those in the no-alcohol condition, and individuals in the placebo condition did not significantly differ from those in the alcohol and no-alcohol conditions. These results suggest that the pharmacological effects of alcohol were important to the occurrence of dating aggression, whereas the effects of expectancy are less clear. Among those less able to engage in cognitive reappraisal, individuals who consumed or believed they consumed alcohol expressed more verbal and physical aggression intentions than those who received no alcohol. Those with higher Arousal who were better able to suppress their emotions expressed fewer verbal and physical aggression intentions than those with lower Arousal. In addition to reducing alcohol consumption, interventions for dating aggression might incorporate emotion regulation skills, with a focus on understanding the circumstances in which cognitive reappraisal and emotion suppression are relatively more effective. (PsycINFO Database Record (c) 2014 APA, all rights reserved).
Daniel Tranel - One of the best experts on this subject based on the ideXlab platform.
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the influence of autonomic Arousal and semantic relatedness on memory for Emotional words
International Journal of Psychophysiology, 2006Co-Authors: Tony W Buchanan, Joset A Etzel, Ralph Adolphs, Daniel TranelAbstract:Increased memory for Emotional stimuli is a well-documented phenomenon. Emotional Arousal during the encoding of a stimulus is one mediator of this memory enhancement. Other variables such as semantic relatedness also play a role in the enhanced memory for Emotional stimuli, especially for verbal stimuli. Research has not addressed the contributions of Emotional Arousal, indexed by self-report and autonomic measures, and semantic relatedness on memory performance. Twenty young adults (10 women) were presented neutral-unrelated words, school-related words, moderately arousing Emotional words, and highly arousing taboo words while heart rate and skin conductance were measured. Memory was tested with free recall and recognition tests. Results showed that taboo words, which were both semantically related and high Arousal were remembered best. School-related words, which were high on semantic relatedness but low on Arousal, were remembered better than the moderately arousing Emotional words and semantically unrelated neutral words. Psychophysiological responses showed that within the moderately arousing Emotional and neutral word groups, those words eliciting greater autonomic activity were better remembered than words that did not elicit such activity. These results demonstrate additive effects of semantic relatedness and Emotional Arousal on memory. Relatedness confers an advantage to memory (as in the school-words), but the combination of relatedness and Arousal (as in the taboo words) results in the best memory performance.
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gastric myoelectrical activity as an index of Emotional Arousal
International Journal of Psychophysiology, 2006Co-Authors: Eduardo P M Vianna, Daniel TranelAbstract:Autonomic nervous system parameters such as electrodermal activity, heart rate, and facial EMG have been utilized extensively as measures of Emotional Arousal. One measure that has rarely been employed in this setting is gastric myoelectrical activity, despite the fact that "gut feelings" have an obvious and even profound role in everyday Emotional life. It has been shown that the gastrointestinal system changes wall tonus and contraction rate during stressful tasks. However, the effects of Emotionally salient stimuli on gastrointestinal motility have scarcely been studied. In the current study, Emotional film clips designed to elicit happiness, disgust, fear, sadness, or no emotion (neutral) were presented to 16 normal participants. Electrogastrogram (EGG), skin conductance, and heart rate were measured while the participants viewed the film clips, and participants rated subjective Arousal intensity and pleasantness of the film clips. We found that Emotional film clips reliably induced the intended subjective feeling states. Also, EGG peak amplitudes in fear, disgust, sadness and happiness were higher than in the no emotion condition. There was a strong positive correlation (r=0.64) between EGG peak amplitude and subjective ratings of Arousal. This is the first evidence that gastric myoelectrical activity is strongly correlated with Arousal ratings to Emotionally salient stimuli, and it suggests that EGG may add useful information about how the body contributes to the phenomenology of emotion and feeling.
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a role for the human amygdala in recognizing Emotional Arousal from unpleasant stimuli
Psychological Science, 1999Co-Authors: Ralph Adolphs, James A Russell, Daniel TranelAbstract:Functional neuroimaging and lesion-based neuropsycho- logical experiments have demonstrated the human amygdala's role in recognition of certain emotions signaled by sensory stimuli, notably, fear and anger in facial expressions. We examined recognition of two Emotional dimensions, Arousal and valence, in a rare subject with complete, bilateral damage restricted to the amygdala. Recognition of Emotional Arousal was impaired for facial expressions, words, and sentences that depicted unpleasant emotions, especially in regard to fear and anger. However, recognition of Emotional valence was nor- mal. The findings suggest that the amygdala plays a critical role in knowledge concerning the Arousal of negative emotions, a function that may explain the impaired recognition of fear and anger in patients with bilateral amygdala damage, and one that is consistent with the amygdala's role in processing stimuli related to threat and danger. Studies in humans provide strong evidence for neural systems that are specialized for the recognition of certain emotions. Some of the clearest evidence comes from studies of patients with damage to the amygdala, a brain structure long thought to play an important role in emotion. Bilateral amygdala damage disproportionately impairs the recognition of unpleasant emotions, especially fear, in facial expres- sions (Adolphs, Tranel, Damasio, & Damasio, 1994, 1995; Broks et amygdala may be critical to process a class of emotions that are high- ly arousing and related to threat and danger. We hypothesized that the human brain contains neural systems spe- cialized to recognize Emotional Arousal in negatively valenced stimuli, and that the amygdala is one key component of such systems. We test- ed this hypothesis by asking a rare subject with complete, selective bilateral amygdala damage to rate Emotional stimuli explicitly with respect to the two attributes of Arousal and valence.
Ralph Adolphs - One of the best experts on this subject based on the ideXlab platform.
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the influence of autonomic Arousal and semantic relatedness on memory for Emotional words
International Journal of Psychophysiology, 2006Co-Authors: Tony W Buchanan, Joset A Etzel, Ralph Adolphs, Daniel TranelAbstract:Increased memory for Emotional stimuli is a well-documented phenomenon. Emotional Arousal during the encoding of a stimulus is one mediator of this memory enhancement. Other variables such as semantic relatedness also play a role in the enhanced memory for Emotional stimuli, especially for verbal stimuli. Research has not addressed the contributions of Emotional Arousal, indexed by self-report and autonomic measures, and semantic relatedness on memory performance. Twenty young adults (10 women) were presented neutral-unrelated words, school-related words, moderately arousing Emotional words, and highly arousing taboo words while heart rate and skin conductance were measured. Memory was tested with free recall and recognition tests. Results showed that taboo words, which were both semantically related and high Arousal were remembered best. School-related words, which were high on semantic relatedness but low on Arousal, were remembered better than the moderately arousing Emotional words and semantically unrelated neutral words. Psychophysiological responses showed that within the moderately arousing Emotional and neutral word groups, those words eliciting greater autonomic activity were better remembered than words that did not elicit such activity. These results demonstrate additive effects of semantic relatedness and Emotional Arousal on memory. Relatedness confers an advantage to memory (as in the school-words), but the combination of relatedness and Arousal (as in the taboo words) results in the best memory performance.
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Emotional Arousal in agenesis of the corpus callosum
International Journal of Psychophysiology, 2006Co-Authors: Lynn K Paul, Aaron Lautzenhiser, Warren S Brown, Arch Hart, Dirk Neumann, Michael L Spezio, Ralph AdolphsAbstract:While the processing of verbal and psychophysiological indices of Emotional Arousal have been investigated extensively in relation to the left and right cerebral hemispheres, it remains poorly understood how both hemispheres normally function together to generate Emotional responses to stimuli. Drawing on a unique sample of nine high-functioning subjects with complete agenesis of the corpus callosum (AgCC), we investigated this issue using standardized Emotional visual stimuli. Compared to healthy controls, subjects with AgCC showed a larger variance in their cognitive ratings of valence and Arousal, and an insensitivity to the emotion category of the stimuli, especially for negatively-valenced stimuli, and especially for their Arousal. Despite their impaired cognitive ratings of Arousal, some subjects with AgCC showed large skin-conductance responses, and in general skin-conductance responses discriminated emotion categories and correlated with stimulus Arousal ratings. We suggest that largely intact right hemisphere mechanisms can support psychophysiological Emotional responses, but that the lack of interhemispheric communication between the hemispheres, perhaps together with dysfunction of the anterior cingulate cortex, interferes with normal verbal ratings of Arousal, a mechanism in line with some models of alexithymia.
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a role for the human amygdala in recognizing Emotional Arousal from unpleasant stimuli
Psychological Science, 1999Co-Authors: Ralph Adolphs, James A Russell, Daniel TranelAbstract:Functional neuroimaging and lesion-based neuropsycho- logical experiments have demonstrated the human amygdala's role in recognition of certain emotions signaled by sensory stimuli, notably, fear and anger in facial expressions. We examined recognition of two Emotional dimensions, Arousal and valence, in a rare subject with complete, bilateral damage restricted to the amygdala. Recognition of Emotional Arousal was impaired for facial expressions, words, and sentences that depicted unpleasant emotions, especially in regard to fear and anger. However, recognition of Emotional valence was nor- mal. The findings suggest that the amygdala plays a critical role in knowledge concerning the Arousal of negative emotions, a function that may explain the impaired recognition of fear and anger in patients with bilateral amygdala damage, and one that is consistent with the amygdala's role in processing stimuli related to threat and danger. Studies in humans provide strong evidence for neural systems that are specialized for the recognition of certain emotions. Some of the clearest evidence comes from studies of patients with damage to the amygdala, a brain structure long thought to play an important role in emotion. Bilateral amygdala damage disproportionately impairs the recognition of unpleasant emotions, especially fear, in facial expres- sions (Adolphs, Tranel, Damasio, & Damasio, 1994, 1995; Broks et amygdala may be critical to process a class of emotions that are high- ly arousing and related to threat and danger. We hypothesized that the human brain contains neural systems spe- cialized to recognize Emotional Arousal in negatively valenced stimuli, and that the amygdala is one key component of such systems. We test- ed this hypothesis by asking a rare subject with complete, selective bilateral amygdala damage to rate Emotional stimuli explicitly with respect to the two attributes of Arousal and valence.