Muscle electrical activity, or "electromyogenic" (EMG) artifact, poses a serious threat to the validity of electroencephalography (EEG) investigations in the frequency domain. EMG is sensitive to a variety of psychological processes and can mask genuine effects or masquerade as legitimate neurogenic effects across the scalp in frequencies at least as low as the alpha band (8-13 Hz). Although several techniques for correcting myogenic activity have been described, most are subjected to only limited validation attempts. Attempts to gauge the impact of EMG correction on intracerebral source models (source "localization" analyses) are rarer still. Accordingly, we assessed the sensitivity and specificity of one prominent correction tool, independent component analysis (ICA), on the scalp and in the source-space using high-resolution EEG. Data were collected from 17 participants while neurogenic and myogenic activity was independently varied. Several protocols for classifying and discarding components classified as myogenic and non-myogenic artifact (e.g., ocular) were systematically assessed, leading to the exclusion of one-third to as much as three-quarters of the variance in the EEG. Some, but not all, of these protocols showed adequate performance on the scalp. Indeed, performance was superior to previously validated regression-based techniques. Nevertheless, ICA-based EMG correction exhibited low validity in the intracerebral source-space, likely owing to incomplete separation of neurogenic from myogenic sources. Taken with prior work, this indicates that EMG artifact can substantially distort estimates of intracerebral spectral activity. Neither regression- nor ICA-based EMG correction techniques provide complete safeguards against such distortions. In light of these results, several practical suggestions and recommendations are made for intelligently using ICA to minimize EMG and other common artifacts.
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Meditation is approached as a technique for the activation of religious experience. Various theories used in psychology to explain the cognitive changes brought about by meditation are briefly reviewed. Of these, the role-theory of Sundén fits best the structure and function of various meditation methods in religious history. A small scale laboratory experiment is reported, designed for the purpose of testing the predictive validity of role-theory. The results make it possible to specify the theory's contribution and limitation.
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Recent neuroimaging and neuropsychological work has begun to shed light on how the brain responds to the viewing of facial expressions of emotion. However, one important category of facial expression that has not been studied on this level is the facial expression of pain. We investigated the neural response to pain expressions by performing functional magnetic resonance imaging (fMRI) as subjects viewed short video sequences showing faces expressing either moderate pain or, for comparison, no pain. In alternate blocks, the same subjects received both painful and non-painful thermal stimulation. Facial expressions of pain were found to engage cortical areas also engaged by the first-hand experience of pain, including anterior cingulate cortex and insula. The reported findings corroborate other work in which the neural response to witnessed pain has been examined from other perspectives. In addition, they lend support to the idea that common neural substrates are involved in representing one's own and others' affective states.
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Reputation systems promote cooperation and deter antisocial behavior in groups. Little is known, however, about how and why people share reputational information. Here, we seek to establish the existence and dynamics of prosocial gossip, the sharing of negative evaluative information about a target in a way that protects others from antisocial or exploitative behavior. We present a model of prosocial gossip and the results of 4 studies testing the model's claims. Results of Studies 1 through 3 demonstrate that (a) individuals who observe an antisocial act experience negative affect and are compelled to share information about the antisocial actor with a potentially vulnerable person, (b) sharing such information reduces negative affect created by observing the antisocial behavior, and (c) individuals possessing more prosocial orientations are the most motivated to engage in such gossip, even at a personal cost, and exhibit the greatest reduction in negative affect as a result. Study 4 demonstrates that prosocial gossip can effectively deter selfishness and promote cooperation. Taken together these results highlight the roles of prosocial motivations and negative affective reactions to injustice in maintaining reputational information sharing in groups. We conclude by discussing implications for reputational theories of the maintenance of cooperation in human groups.
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We present a novel weighted Fourier series (WFS) representation for cortical surfaces. The WFS representation is a data smoothing technique that provides the explicit smooth functional estimation of unknown cortical boundary as a linear combination of basis functions. The basic properties of the representation are investigated in connection with a self-adjoint partial differential equation and the traditional spherical harmonic (SPHARM) representation. To reduce steep computational requirements, a new iterative residual fitting (IRF) algorithm is developed. Its computational and numerical implementation issues are discussed in detail. The computer codes are also available at http://www.stat.wisc.edu/-mchung/softwares/weighted.SPHARM/weighted-SPHARM.html. As an illustration, the WFS is applied i n quantifying the amount ofgray matter in a group of high functioning autistic subjects. Within the WFS framework, cortical thickness and gray matter density are computed and compared.
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<p>This article opens by noting that positive emotions do not fit existing models of emotions. Consequently, a new model is advanced to describe the form and function of a subset of positive emotions, including joy, interest, contentment, and love. This new model posits that these positive emotions serve to broaden an individual's momentary thought-action repertoire, which in turn has the effect of building that individual's physical, intellectual, and social resources. Empirical evidence to support this broaden-and-build model of positive emotions is reviewed, and implications for emotion regulation and health promotion are discussed.</p>
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One of the most important goals and outcomes of social life is to attain status in the groups to which we belong. Such face-to-face status is defined by the amount of respect, influence, and prominence each member enjoys in the eyes of the others. Three studies investigated personological determinants of status in social groups (fraternity, sorority, and dormitory), relating the Big Five personality traits and physical attractiveness to peer ratings of status. High Extraversion substantially predicted elevated status for both sexes. High Neuroticism, incompatible with male gender norms, predicted lower status in men. None of the other Big Five traits predicted status. These effects were independent of attractiveness, which predicted higher status only in men. Contrary to previous claims, women's status ordering was just as stable as men's but emerged later. Discussion focuses on personological pathways to attaining status and on potential mediators.
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At the turn of the twentieth century, the mind-cure movement emphasized the healing power of positive emotions and beliefs. William James defended mind-cure during the Massachusetts legislature's debates on licensing physicians in 1894 and 1898. In The Varieties of Religious Experience (1902) he used the movement's therapeutic claims to illustrate the typically American, practical turn of the "religion of healthy-mindedness." Varieties sympathetically surveys mind-cure literature, but also criticizes healthy-minded religion for its limited range and refusal to confront tragedy and radical evil. Many of today's mind/body therapies continue the mind-cure tradition and retain the limitations that James noted.
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Stephen Cope asked 25 yoga and meditation teachers to share their "tales from the path"--their thoughts on how the long-term practice of yoga and meditation has changed their lives. The result is a unique collection of stories offering insight and inspiration for everyone seeking a more satisfying life.
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<p>Some common conceptions of Buddhist meditative practice emphasize the elimination of emotion and desire in the interest of attaining tranquility and spiritual perfection. But to place too strong an emphasis on this is to miss an important social element emphasized by major figures in the Mahāyāna and Chan/Zen Buddhist traditions who are critical of these quietistic elements and who stress instead an understanding of an enlightenment that emphasizes enriched sociality and flexible readiness to engage, and not avoid, life’s fluctuations in fortune and essential impermanence. It is argued here that these criticisms of quietism are bolstered by recent advances in the philosophy and psychology of the emotions that highlight the role of emotions in framing the context of decision making—that is, in sorting out the relevant from the irrelevant, identifying salience, and directing decisions when uncertainty prevents definitive judgment. This research makes clearer why self-liberation is fundamentally a matter of liberation from judgmental habit and inflexibility, and lends support to a view of enlightenment that emphasizes compassionate engagement with others. It also provides for a more plausible picture of the cognitive transformation involved in liberation and sheds light on the rationale for certain traditional Chan and Zen teaching tactics, such as those involving koan introspection.</p>
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