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The experience of pain occurs when the level of a stimulus is sufficient to elicit a marked affective response, putatively to warn the organism of potential danger and motivate appropriate behavioral responses. Understanding the biological mechanisms of the transition from innocuous to painful levels of sensation is essential to understanding pain perception as well as clinical conditions characterized by abnormal relationships between stimulation and pain response. Thus, the primary objective of this study was to characterize the neural response associated with this transition and the correspondence between that response and subjective reports of pain. Towards this goal, this study examined BOLD response profiles across a range of temperatures spanning the pain threshold. 14 healthy adults underwent functional magnetic resonance imaging (fMRI) while a range of thermal stimuli (44-49°C) were applied. BOLD responses showed a sigmoidal profile along the range of temperatures in a network of brain regions including insula and mid-cingulate, as well as a number of regions associated with motor responses including ventral lateral nuclei of the thalamus, globus pallidus and premotor cortex. A sigmoid function fit to the BOLD responses in these regions explained up to 85% of the variance in individual pain ratings, and yielded an estimate of the temperature of steepest transition from non-painful to painful heat that was nearly identical to that generated by subjective ratings. These results demonstrate a precise characterization of the relationship between objective levels of stimulation, resulting neural activation, and subjective experience of pain and provide direct evidence for a neural mechanism supporting the nonlinear transition from innocuous to painful levels along the sensory continuum.
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Although the systematic study of meditation is still in its infancy, research has provided evidence for meditation-induced improvements in psychological and physiological well-being. Moreover, meditation practice has been shown not only to benefit higher-order cognitive functions but also to alter brain activity. Nevertheless, little is known about possible links to brain structure. Using high-resolution MRI data of 44 subjects, we set out to examine the underlying anatomical correlates of long-term meditation with different regional specificity (i.e., global, regional, and local). For this purpose, we applied voxel-based morphometry in association with a recently validated automated parcellation approach. We detected significantly larger gray matter volumes in meditators in the right orbito-frontal cortex (as well as in the right thalamus and left inferior temporal gyrus when co-varying for age and/or lowering applied statistical thresholds). In addition, meditators showed significantly larger volumes of the right hippocampus. Both orbito-frontal and hippocampal regions have been implicated in emotional regulation and response control. Thus, larger volumes in these regions might account for meditators' singular abilities and habits to cultivate positive emotions, retain emotional stability, and engage in mindful behavior. We further suggest that these regional alterations in brain structures constitute part of the underlying neurological correlate of long-term meditation independent of a specific style and practice. Future longitudinal analyses are necessary to establish the presence and direction of a causal link between meditation practice and brain anatomy.

Teasing requires the ability to understand intention, nonliteral communication, pretense, and social context. Children with autism experience difficulty with such skills, and consequently, are expected to have difficulty with teasing. To better understand teasing concepts and behaviors, children with autism, their parents, and age and Verbal-IQ-matched comparison children and parents described concepts and experiences of teasing and engaged in a parent–child teasing interaction. The teasing of children with autism was less playful and provocative and focused less on social norms than that of comparison children. Similarly, parents of children with autism teased in less playful ways. Scores on a theory of mind task accounted for several of the observed differences. Discussion focused on the importance of understanding social context and playful behavior during teasing.
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In this article, I argue that educators can utilize mindfulness practices to enhance the efficacy of anti-oppressive pedagogy. The philosophies of Wittgenstein and Nagarjuna provide a holistic human ontology and show that learning affects students at all levels: mind, body, emotion, and spirit. My analysis of the phenomenology of thinking reveals the modes of relationship to ideation. I have proposed mindfulness practice as a proven technique to address the non-cognitive forms of attachment to ideation that may remain in force despite the most thorough-going intellectual change. /// Dans cet article, l'auteure fait valoir que les enseignants peuvent utiliser des pratiques attentionnées pour augmenter l'efficacité de la pédagogie libertaire. Les philosophies de Wittgenstein et de Nagarjuna permettent une ontologie humaine holistique et démontrent que l'apprentissage affecte les étudiants sur tous les plans: l'intelligence, le corps, les émotions et l'esprit. Les analyses de la phénoménologie de la pensée révèlent les types de relation à l'idéation. La pratique attentionnée est proposée comme une technique qui a fait ses preuves pour traiter les formes d'attachement hors du champ cognitif à l'idéation qui demeure active malgré le plus profond changement intellectuel.

OBJECTIVES: Affective neuroscience research that investigates core symptoms of pediatric bipolar disorder (PBD) may be effective in differentiating PBD phenotypes. The current study used affect-modulated startle to examine potential differences in reactivity to emotional stimuli (reward and punishment) in narrow and broad phenotype PBD and controls. METHODS: Thirty children meeting DSM-IV bipolar disorder criteria (i.e. narrow phenotype PBD with defined manic episodes with elevated/expansive mood), 19 children meeting criteria for severe mood dysregulation (i.e. broad phenotype with chronic irritability, hyper-reactivity, and hyperarousal), and 19 controls completed a lottery startle paradigm involving reward (money) and punishment (loud noise). Startle probes were presented during anticipation of the emotional stimulus, immediately following the presentation of the stimulus, or during return to baseline following the stimulus. RESULTS: By self-report, patients and controls found the putative punishment to be preferable to the neutral condition. In the reward condition, patient samples reported greater arousal than did controls, but no between-group differences were found on the magnitude of startle response during the reward, punishment, or neutral conditions. CONCLUSIONS: The failure to find differences in affect-modulated startle between control children and those with narrow or broad PBD phenotypes speaks to the methodological challenges associated with studying reward mechanisms in PBD. Alternative paradigms that focus on different aspects of reward mechanisms are discussed.
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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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EEG and EEG source-estimation are susceptible to electromyographic artifacts (EMG) generated by the cranial muscles. EMG can mask genuine effects or masquerade as a legitimate effect-even in low frequencies, such as alpha (8-13 Hz). Although regression-based correction has been used previously, only cursory attempts at validation exist, and the utility for source-localized data is unknown. To address this, EEG was recorded from 17 participants while neurogenic and myogenic activity were factorially varied. We assessed the sensitivity and specificity of four regression-based techniques: between-subjects, between-subjects using difference-scores, within-subjects condition-wise, and within-subject epoch-wise on the scalp and in data modeled using the LORETA algorithm. Although within-subject epoch-wise showed superior performance on the scalp, no technique succeeded in the source-space. Aside from validating the novel epoch-wise methods on the scalp, we highlight methods requiring further development.
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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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[F-18]Mefway was developed to provide an F-18 labeled positron emission tomography (PET) neuroligand with high affinity for the serotonin 5-HT(1A) receptor to improve the in vivo assessment of the 5-HT(1A) system. The goal of this work was to compare the in vivo kinetics of [F-18]mefway, [F-18]MPPF, and [C-11]WAY100635 in the rhesus monkey. METHODS: Each of four monkeys were given bolus injections of [F-18]mefway, [C-11]WAY100635, and [F-18]MPPF and scans were acquired with a microPET P4 scanner. Arterial blood was sampled to assay parent compound throughout the time course of the PET experiment. Time activity curves were extracted in the high 5-HT(1A) binding areas of the anterior cingulate cortex (ACG), mesial temporal cortex, raphe nuclei, and insula cortex. Time activity curves were also extracted in the cerebellum, which was used as a reference region. The in vivo kinetics of the radiotracers were compared based on the nondisplaceable distribution volume (V(ND) ) and binding potential (BP(ND) ). RESULTS: At 30 min, the fraction of radioactivity in the plasma due to parent compound was 19%, 28%, and 29% and cleared from the arterial plasma at rates of 0.0031, 0.0078, and 0.0069 (min⁻¹) ([F-18]mefway, [F-18]MPPF, [C-11]WAY100635). The BP(ND) in the brain regions were mesial temporal cortex: 7.4 ± 0.6, 3.1 ± 0.4, 7.0 ± 1.2, ACG: 7.2 ± 1.2, 2.1 ± 0.2, 7.9 ± 1.2; raphe nuclei: 3.7 ± 0.6, 1.3 ± 0.3, 3.3 ± 0.7; and insula cortex: 4.2 ± 0.6, 1.2 ± 0.1, 4.7 ± 1.0 for [F-18]mefway, [F-18]MPPF, and [C-11]WAY100635 respectively. CONCLUSIONS: In the rhesus monkey, [F-18]mefway has similar in vivo kinetics to [C-11]WAY100635 and yields greater than 2-fold higher BP(ND) than [F-18]MPPF. These properties make [F-18]mefway a promising radiotracer for 5-HT(1A) assay, providing higher counting statistics and a greater dynamic range in BP(ND).
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<p>The human voice is one of the principal conveyers of social and affective communication. Yet relatively little is known about the neural circuitry that supports the recognition of different vocally expressed emotions. We conducted an FMRI study to examine the brain responses to vocal expressions of anger and happiness, and to test whether specific brain regions showed preferential engagement in the processing of one emotion over the other. We also tested the extent to which simultaneously presented facial expressions of the same or different emotions would enhance brain responses, and to what degree such responses depend on attention towards the vocal expression. Forty healthy individuals were scanned while listening to vocal expressions of anger or happiness, while at the same time watching congruent or discrepant facial expressions. Happy voices elicited significantly more activation than angry voices in right anterior and posterior middle temporal gyrus (MTG), left posterior MTG and right inferior frontal gyrus. Furthermore, for the left MTG region, happy voices were related to higher activation only when paired with happy faces. Activation in the left insula, left amygdala and hippocampus, and rostral anterior cingulate cortex showed an effect of selectively attending to the vocal stimuli. Our results identify a network of regions implicated in the processing of vocal emotion, and suggest a particularly salient role for vocal expressions of happiness.</p>
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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>Research suggests that mindfulness practices offer psychotherapists a way to positively affect aspects of therapy that account for successful treatment. This paper provides psychotherapists with a synthesis of the empirically supported advantages of mindfulness. Definitions of mindfulness and evidence-based interpersonal, affective, and intrapersonal benefits of mindfulness are presented. Research on therapists who meditate and client outcomes of therapists who meditate are reviewed. Implications for practice, research, and training are discussed.</p>

<p>Bourgeault looks to the Gospels, to contemplative experience, and to recently discovered ancient Christian documents (such as the Nag Hammadi scriptures and the Gospel of Thomas) to reveal a fresh new understanding of Jesus and his teaching.</p>

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