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The brain circuitry underlying emotion includes several territories of the prefrontal cortex (PFC), the amygdala, hippocampus, anterior cingulate, and related structures. In general, the PFC represents emotion in the absence of immediately present incentives and thus plays a crucial role in the anticipation of the future affective consequences of action, as well as in the persistence of emotion following the offset of an elicitor. The functions of the other structures in this circuit are also considered. Individual differences in this circuitry are reviewed, with an emphasis on asymmetries within the PFC and activation of the amygdala as 2 key components of affective style. These individual differences are related to both behavioral and biological variables associated with affective style and emotion regulation. Plasticity in this circuitry and its implications for transforming emotion and cultivating positive affect and resilience are considered.
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The amygdalae are important, if not critical, brain regions for many affective, attentional and memorial processes, and dysfunction of the amygdalae has been a consistent finding in the study of clinical depression. Theoretical models of the functional neuroanatomy of both normal and psychopathological affective processes which posit cortical hemispheric specialization of functions have been supported by both lesion and functional neuroimaging studies in humans. Results from human neuroimaging studies in support of amygdalar hemispheric specialization are inconsistent. However, recent results from human lesion studies are consistent with hemispheric specialization. An important, yet largely ignored, feature of the amygdalae in the primate brain--derived from both neuroanatomical and electrophysiological data--is that there are virtually no direct interhemispheric connections via the anterior commissure (AC). This feature stands in stark contrast to that of the rodent brain wherein virtually all amygdalar nuclei have direct interhemispheric connections. We propose this feature of the primate brain, in particular the human brain, is a result of influences from frontocortical hemispheric specialization which have developed over the course of primate brain evolution. Results consistent with this notion were obtained by examining the nature of human amygdalar interhemispheric connectivity using both functional magnetic resonance imaging (FMRI) and positron emission tomography (PET). We found modest evidence of amygdalar interhemispheric functional connectivity in the non-depressed brain, whereas there was strong evidence of functional connectivity in the depressed brain. We interpret and discuss the nature of this connectivity in the depressed brain in the context of dysfunctional frontocortical-amygdalar interactions which accompany clinical depression.
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BACKGROUND: Autism is a syndrome of unknown cause, marked by abnormal development of social behavior. Attempts to link pathological features of the amygdala, which plays a key role in emotional processing, to autism have shown little consensus. OBJECTIVE: To evaluate amygdala volume in individuals with autism spectrum disorders and its relationship to laboratory measures of social behavior to examine whether variations in amygdala structure relate to symptom severity. DESIGN: We conducted 2 cross-sectional studies of amygdala volume, measured blind to diagnosis on high-resolution, anatomical magnetic resonance images. Participants were 54 males aged 8 to 25 years, including 23 with autism and 5 with Asperger syndrome or pervasive developmental disorder not otherwise specified, recruited and evaluated at an academic center for developmental disabilities and 26 age- and sex-matched community volunteers. The Autism Diagnostic Interview-Revised was used to confirm diagnoses and to validate relationships with laboratory measures of social function. MAIN OUTCOME MEASURES: Amygdala volume, judgment of facial expressions, and eye tracking. RESULTS: In study 1, individuals with autism who had small amygdalae were slowest to distinguish emotional from neutral expressions (P=.02) and showed least fixation of eye regions (P=.04). These same individuals were most socially impaired in early childhood, as reported on the Autism Diagnostic Interview-Revised (P<.04). Study 2 showed smaller amygdalae in individuals with autism than in control subjects (P=.03) and group differences in the relation between amygdala volume and age. Study 2 also replicated findings of more gaze avoidance and childhood impairment in participants with autism with the smallest amygdalae. Across the combined sample, severity of social deficits interacted with age to predict different patterns of amygdala development in autism (P=.047). CONCLUSIONS: These findings best support a model of amygdala hyperactivity that could explain most volumetric findings in autism. Further psychophysiological and histopathological studies are indicated to confirm these findings.
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This article presents an overview of the author's recent electrophysiological studies of anterior cerebral asymmetries related to emotion and affective style. A theoretical account is provided of the role of the two hemispheres in emotional processing. This account assigns a major role in approach- and withdrawal-related behavior to the left and right frontal and anterior temporal regions of two hemispheres, respectively. Individual differences in approach- and withdrawal-related emotional reactivity and temperament are associated with stable differences in baseline measures of activation asymmetry in these anterior regions. Phasic state changes in emotion result in shifts in anterior activation asymmetry which are superimposed upon these stable baseline differences. Future directions for research in this area are discussed.
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OBJECTIVE: The anterior cingulate cortex has been implicated in depression. Results are best interpreted by considering anatomic and cytoarchitectonic subdivisions. Evidence suggests depression is characterized by hypoactivity in the dorsal anterior cingulate, whereas hyperactivity in the rostral anterior cingulate is associated with good response to treatment. The authors tested the hypothesis that activity in the rostral anterior cingulate during the depressed state has prognostic value for the degree of eventual response to treatment. Whereas prior studies used hemodynamic imaging, this investigation used EEG. METHOD: The authors recorded 28-channel EEG data for 18 unmedicated patients with major depression and 18 matched comparison subjects. Clinical outcome was assessed after nortriptyline treatment. Of the 18 depressed patients, 16 were considered responders 4-6 months after initial assessment. A median split was used to classify response, and the pretreatment EEG data of patients showing better (N=9) and worse (N=9) responses were analyzed with low-resolution electromagnetic tomography, a new method to compute three-dimensional cortical current density for given EEG frequency bands according to a Talairach brain atlas. RESULTS: The patients with better responses showed hyperactivity (higher theta activity) in the rostral anterior cingulate (Brodmann's area 24/32). Follow-up analyses demonstrated the specificity of this finding, which was not confounded by age or pretreatment depression severity. CONCLUSIONS: These results, based on electrophysiological imaging, not only support hemodynamic findings implicating activation of the anterior cingulate as a predictor of response in depression, but they also suggest that differential activity in the rostral anterior cingulate is associated with gradations of response.
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OBJECTIVE: The anticipation of adverse outcomes, or worry, is a cardinal symptom of generalized anxiety disorder. Prior work with healthy subjects has shown that anticipating aversive events recruits a network of brain regions, including the amygdala and anterior cingulate cortex. This study tested whether patients with generalized anxiety disorder have alterations in anticipatory amygdala function and whether anticipatory activity in the anterior cingulate cortex predicts treatment response. METHOD: Functional magnetic resonance imaging (fMRI) was employed with 14 generalized anxiety disorder patients and 12 healthy comparison subjects matched for age, sex, and education. The event-related fMRI paradigm was composed of one warning cue that preceded aversive pictures and a second cue that preceded neutral pictures. Following the fMRI session, patients received 8 weeks of treatment with extended-release venlafaxine. RESULTS: Patients with generalized anxiety disorder showed greater anticipatory activity than healthy comparison subjects in the bilateral dorsal amygdala preceding both aversive and neutral pictures. Building on prior reports of pretreatment anterior cingulate cortex activity predicting treatment response, anticipatory activity in that area was associated with clinical outcome 8 weeks later following treatment with venlafaxine. Higher levels of pretreatment anterior cingulate cortex activity in anticipation of both aversive and neutral pictures were associated with greater reductions in anxiety and worry symptoms. CONCLUSIONS: These findings of heightened and indiscriminate amygdala responses to anticipatory signals in generalized anxiety disorder and of anterior cingulate cortex associations with treatment response provide neurobiological support for the role of anticipatory processes in the pathophysiology of generalized anxiety disorder.
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This article reviews the modern literature on two key aspects of the central circuitry of emotion: the prefrontal cortex (PFC) and the amygdala. There are several different functional divisions of the PFC, including the dorsolateral, ventromedial, and orbital sectors. Each of these regions plays some role in affective processing that shares the feature of representing affect in the absence of immediate rewards and punishments as well as in different aspects of emotional regulation. The amygdala appears to be crucial for the learning of new stimulus-threat contingencies and also appears to be important in the expression of cue-specific fear. Individual differences in both tonic activation and phasic reactivity in this circuit play an important role in governing different aspects of anxiety. Emphasis is placed on affective chronometry, or the time course of emotional responding, as a key attribute of individual differences in propensity for anxiety that is regulated by this circuitry.
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<p>Drawing its main source of inspiration from a naturalized interpretation of Husserlian phenomenology, On Becoming Aware: A Pragmatics of Experiencing attempts to examine closely the nature of experience and how we may become aware of our own mental life. The authors also focus on how this project fits into the larger context of cognitive science, psychology, neurosciences, and philosophy. Additional partners in the effort to better understand experience are the contemplative systems of the world's spiritual or wisdom traditions, including particularly that of Buddhism. The book includes three separate glossaries of technical terms in phenomenology, the cognitive sciences, and Tibetan Buddhism. The book On Becoming Aware seeks a disciplined and practical approach to exploring human experience. While much of the book draws its inspiration from the phenomenological theories of Husserl, other approaches to the direct study of experience are also explored in depth. One of these approaches is embodied by the world's spiritual or wisdom or contemplative traditions such as Sufism, Buddhism, the Philokalia tradition, and others. Collectively, these traditions have come upon a variety of their own insights and methods for understanding experience, or, to use words from the phenomenological tradition, has developed its own ways of phenomenological reduction Amongst the various wisdom traditions, the authors focus mainly on Buddhism. The authors give an introduction to Buddhist theory and history, followed by an in-depth discussion of the Buddhist contemplative practices of mindfulness, śamatha, vipaśyanā, tonglen (gtong len), lojong (blo sbyong), dzokchen (rdzogs chen), and mahāmudrā. The authors then relate this discussion to themes from philosophy and phenomenology explored earlier in the book, paricularly Husserl's concept of épochè. (Zach Rowinski 2005-01-17) Publisher's description: This book searches for the sources and means for a disciplined practical approach to exploring human experience. The spirit of this book is pragmatic and relies on a Husserlian phenomenology primarily understood as a method of exploring our experience. The authors do not aim at a neo-Kantian a priori ‘new theory’ of experience but instead they describe a concrete activity: how we examine what we live through, how we become aware of our own mental life. The range of experiences of which we can become aware is vast: all the normal dimensions of human life (perception, motion, memory, imagination, speech, everyday social interactions), cognitive events that can be precisely defined as tasks in laboratory experiments (e.g., a protocol for visual attention), but also manifestations of mental life more fraught with meaning (dreaming, intense emotions, social tensions, altered states of consciousness). The central assertion in this work is that this immanent ability is habitually ignored or at best practiced unsystematically, that is to say, blindly. Exploring human experience amounts to developing and cultivating this basic ability through specific training. Only a hands-on, non-dogmatic approach can lead to progress, and that is what animates this book.</p>

Many of us go through our daily lives on autopilot, not fully aware of our conscious experiences. In a discussion moderated by Steve Paulson, executive producer and host of To the Best of Our Knowledge, neuroscientists Richard Davidson and Amishi Jha and clinical mindfulness expert Jon Kabat-Zinn explore the role of consciousness in mental and physical health, how we can train our minds to be more flexible and adaptable, and cutting-edge neuroscience findings about the transformation of consciousness through mindfulness and contemplative practice. The following is an edited transcript of the discussion that occurred February 6, 2013, 7:00-8:15 PM, at the New York Academy of Sciences in New York City.

Many of us go through our daily lives on autopilot, not fully aware of our conscious experiences. In a discussion moderated by Steve Paulson, executive producer and host of To the Best of Our Knowledge, neuroscientists Richard Davidson and Amishi Jha and clinical mindfulness expert Jon Kabat-Zinn explore the role of consciousness in mental and physical health, how we can train our minds to be more flexible and adaptable, and cutting-edge neuroscience findings about the transformation of consciousness through mindfulness and contemplative practice. The following is an edited transcript of the discussion that occurred February 6, 2013, 7:00-8:15 PM, at the New York Academy of Sciences in New York City.
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<p>Mindfulness is an attribute of consciousness long believed to promote well-being. This research provides a theoretical and empirical examination of the role of mindfulness in psychological well-being. The development and psychometric properties of the dispositional Mindful Attention Awareness Scale (MAAS) are described. Correlational, quasi-experimental, and laboratory studies then show that the MAAS measures a unique quality of consciousness that is related to a variety of well-being constructs, that differentiates mindfulness practitioners from others, and that is associated with enhanced self-awareness. An experience-sampling study shows that both dispositional and state mindfulness predict self-regulated behavior and positive emotional states. Finally, a clinical intervention study with cancer patients demonstrates that increases in mindfulness over time relate to declines in mood disturbance and stress.</p>

BACKGROUND: Studies using electroencephalogram (EEG) measures of activation asymmetry have reported differences in anterior asymmetry between depressed and nondepressed subjects. Several studies have suggested reciprocal relations between measures of anterior and posterior activation asymmetries. We hypothesized that depressed subjects would fail to show the normal activation of posterior right hemisphere regions in response to an appropriate cognitive challenge. METHODS: EEG activity was recorded from 11 depressed and 19 nondepressed subjects during the performance of psychometrically matched verbal (word finding) and spatial (dot localization) tasks. Band power was extracted from all epochs of artifact-free data and averaged within each condition. Task performance was also assessed. RESULTS: Depressed subjects showed a specific deficit in the performance of the spatial task, whereas no group differences were evident on verbal performance. In posterior scalp regions, nondepressed controls had a pattern of relative left-sided activation during the verbal task and relative right-sided activation during the spatial task. In contrast, depressed subjects failed to show activation in posterior right hemisphere regions during spatial task performance. CONCLUSIONS: These findings suggest that deficits in right posterior functioning underlie the observed impairments in spatial functioning among depressed subjects.
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BACKGROUND: The frontal lobe has been crucially involved in the neurobiology of major depression, but inconsistencies among studies exist, in part due to a failure of considering modulatory variables such as symptom severity, comorbidity with anxiety, and distinct subtypes, as codeterminants for patterns of brain activation in depression. METHODS: Resting electroencephalogram was recorded in 38 unmedicated subjects with major depressive disorder and 18 normal comparison subjects, and analyzed with a tomographic source localization method that computes the cortical three-dimensional distribution of current density for standard electroencephalogram frequency bands. Symptom severity and anxiety were measured via self-report and melancholic features via clinical interview. RESULTS: Depressed subjects showed more excitatory (beta3, 21.5-30.0 Hz) activity in the right superior and inferior frontal lobe (Brodmann's area 9/10/11) than comparison subjects. In melancholic subjects, this effect was particularly pronounced for severe depression, and right frontal activity correlated positively with anxiety. Depressed subjects showed posterior cingulate and precuneus hypoactivity. CONCLUSIONS: While confirming prior results implicating right frontal and posterior cingulate regions, this study highlights the importance of depression severity, anxiety, and melancholic features in patterns of brain activity accompanying depression.
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Fragile X syndrome (FXS) is the most commonly known genetic disorder associated with autism spectrum disorder (ASD). Overlapping features in these populations include gaze aversion, communication deficits, and social withdrawal. Although the association between FXS and ASD has been well documented at the behavioral level, the underlying neural mechanisms associated with the social/emotional deficits in these groups remain unclear. We collected functional brain images and eye-gaze fixations from 9 individuals with FXS and 14 individuals with idiopathic ASD, as well as 15 typically developing (TD) individuals, while they performed a facial-emotion discrimination task. The FXS group showed a similar yet less aberrant pattern of gaze fixations compared with the ASD group. The FXS group also showed fusiform gyrus (FG) hypoactivation compared with the TD control group. Activation in FG was strongly and positively associated with average eye fixation and negatively associated with ASD characteristics in the FXS group. The FXS group displayed significantly greater activation than both the TD control and ASD groups in the left hippocampus (HIPP), left superior temporal gyrus (STG), right insula (INS), and left postcentral gyrus (PCG). These group differences in brain activation are important as they suggest unique underlying face-processing neural circuitry in FXS versus idiopathic ASD, largely supporting the hypothesis that ASD characteristics in FXS and idiopathic ASD reflect partially divergent impairments at the neural level, at least in FXS individuals without a co-morbid diagnosis of ASD.
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Stimulated by a recent meeting between Western psychologists and the Dalai Lama on the topic of destructive emotions, we report on two issues: the achievement of enduring happiness, what Tibetan Buddhists call sukha, and the nature of afflictive and nonafflictive emotional states and traits. A Buddhist perspective on these issues is presented, along with discussion of the challenges the Buddhist view raises for empirical research and theory.
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Some children show emotion that is not consistent with normative appraisal of the context and can therefore be defined as context inappropriate (CI). The authors used individual growth curve modeling and hierarchical multiple regression analyses to examine whether CI anger predicts differences in hypothalamic-pituitary-adrenal axis activity, as manifest in salivary cortisol measures. About 23% of the 360 children (ages 6-10 years, primarily 7-8) showed at least 1 expression of CI anger in situations designed to elicit positive affect. Expression of anger across 2 positive assessments was less common (around 4%). CI anger predicted the hypothesized lower levels of cortisol beyond that attributed to context appropriate anger. Boys' CI anger predicted lower morning cortisol and flatter slopes. Results suggest that this novel approach to studying children's emotion across varying contexts can provide insight into affective style.
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The heart rate, breathing rate, and skin resistance were recorded for 20 community home girls (Home group) and for 20 age-matched girls from a regular school (School group). The former group had a significantly higher rate of breathing and a more irregular breath pattern known to correlate with high fear and anxiety, than the School group. Skin resistance was significantly lower in the School group, which may suggest greater arousal, 28 girls of the Home group formed 14 pairs, matched for age and duration of stay in the home. Subjects of a pair were randomly assigned to either yoga or games groups. For the former emphasis was on relaxation and awareness, whereas for the latter increasing physical activity was emphasized. At the end of an hour daily for six months both groups showed a significant decrease in the resting heart rate relative to initial values (Wilcoxon paired-sample rest), and the yoga group showed a significant decrease in breath rate, which appeared more regular but no significant increase in the skin resistance. These results suggest that a yoga program which includes relaxation, awareness, and graded physical activity is a useful addition to the routine of community home children.
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Electroencephalographic (EEG) recordings from 19 scalp recording sites were used to differentiate among two posited unique forms of mediation, concentration and mindfulness, and a normal relaxation control condition. Analyzes of all traditional frequency bandwidth data (i.e., delta 1–3 Hz; theta, 4–7 Hz; alpha, 8–12 Hz; beta 1, 13–25 Hz; beta 2, 26–32 Hz) showed strong mean amplitude frequency differences between the two meditation conditions and relaxation over numerous cortical sites. Furthermore, significant differences were obtained between concentration and mindfulness states at all bandwidths. Taken together, our results suggest that concentration and mindfulness “meditations” may be unique forms of consciousness and are not merely degrees of a state of relaxation.

Many spiritual traditions employ certain mental techniques (meditation) which consist in inhibiting mental activity whilst nonetheless remaining fully conscious, which is supposed to lead to a realisation of one’s own true nature prior to habitual self-substantialisation. In this paper I propose that this practice can be understood as a special means of becoming aware of consciousness itself as such. To explain this claim I conduct some phenomenologically oriented considerations about the nature of consciousness qua presence and the problem of self-presence of this presence.

Poor sleep is common in substance use disorders (SUDs) and is a risk factor for relapse. Within the context of a multicomponent, mindfulness-based sleep intervention that included mindfulness meditation (MM) for adolescent outpatients with SUDs (n = 55), this analysis assessed the contributions of MM practice intensity to gains in sleep quality and self-efficacy related to SUDs. Eighteen adolescents completed a 6-session study intervention and questionnaires on psychological distress, sleep quality, mindfulness practice, and substance use at baseline, 8, 20, and 60 weeks postentry. Program participation was associated with improvements in sleep and emotional distress, and reduced substance use. MM practice frequency correlated with increased sleep duration and improvement in self-efficacy about substance use. Increased sleep duration was associated with improvements in psychological distress, relapse resistance, and substance use-related problems. These findings suggest that sleep is an important therapeutic target in substance abusing adolescents and that MM may be a useful component to promote improved sleep.

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