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The impact of using motion estimates as covariates of no interest was examined in general linear modeling (GLM) of both block design and rapid event-related functional magnetic resonance imaging (fMRI) data. The purpose of motion correction is to identify and eliminate artifacts caused by task-correlated motion while maximizing sensitivity to true activations. To optimize this process, a combination of motion correction approaches was applied to data from 33 subjects performing both a block-design and an event-related fMRI experiment, including analysis: (1) without motion correction; (2) with motion correction alone; (3) with motion-corrected data and motion covariates included in the GLM; and (4) with non-motion-corrected data and motion covariates included in the GLM. Inclusion of covariates was found to be generally useful for increasing the sensitivity of GLM results in the analysis of event-related data. When motion parameters were included in the GLM for event-related data, it made little difference if motion correction was actually applied to the data. For the block design, inclusion of motion covariates had a deleterious impact on GLM sensitivity when even moderate correlation existed between motion and the experimental design. Based on these results, we present a general strategy for block designs, event-related designs, and hybrid designs to identify and eliminate probable motion artifacts while maximizing sensitivity to true activations.
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Asthma, like many inflammatory disorders, is affected by psychological stress, suggesting that reciprocal modulation may occur between peripheral factors regulating inflammation and central neural circuitry underlying emotion and stress reactivity. Despite suggestions that emotional factors may modulate processes of inflammation in asthma and, conversely, that peripheral inflammatory signals influence the brain, the neural circuitry involved remains elusive. Here we show, using functional magnetic resonance imaging, that activity in the anterior cingulate cortex and insula to asthma-relevant emotional, compared with valence-neutral stimuli, is associated with markers of inflammation and airway obstruction in asthmatic subjects exposed to antigen. This activation accounts for > or =40% of the variance in the peripheral markers and suggests a neural basis for emotion-induced modulation of airway disease in asthma. The anterior cingulate cortex and insula have been implicated in the affective evaluation of sensory stimulation, regulation of homeostatic responses, and visceral perception. In individuals with asthma and other stress-related conditions, these brain regions may be hyperresponsive to disease-specific emotional and afferent physiological signals, which may contribute to the dysregulation of peripheral processes, such as inflammation.
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Background The information processing capacity of the human mind is limited, as is evidenced by the attentional blink (AB) - a deficit in identifying the second of two temporally-close targets (T1 and T2) embedded in a rapid stream of distracters. Theories of the AB generally agree that it results from competition between stimuli for conscious representation. However, they disagree in the specific mechanisms, in particular about how attentional processing of T1 determines the AB to T2. Methodology/Principal Findings The present study used the high spatial resolution of functional magnetic resonance imaging (fMRI) to examine the neural mechanisms underlying the AB. Our research approach was to design T1 and T2 stimuli that activate distinguishable brain areas involved in visual categorization and representation. ROI and functional connectivity analyses were then used to examine how attentional processing of T1, as indexed by activity in the T1 representation area, affected T2 processing. Our main finding was that attentional processing of T1 at the level of the visual cortex predicted T2 detection rates Those individuals who activated the T1 encoding area more strongly in blink versus no-blink trials generally detected T2 on a lower percentage of trials. The coupling of activity between T1 and T2 representation areas did not vary as a function of conscious T2 perception. Conclusions/Significance These data are consistent with the notion that the AB is related to attentional demands of T1 for selection, and indicate that these demands are reflected at the level of visual cortex. They also highlight the importance of individual differences in attentional settings in explaining AB task performance.
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<p>A list of 119 Sanskrit-Tibetan equations. (Michael Walter and Manfred Taube 2006-05-15, revised by Bill McGrath 2008-01-03)</p>

The response to painful stimulation depends not only on peripheral nociceptive input but also on the cognitive and affective context in which pain occurs. One contextual variable that affects the neural and behavioral response to nociceptive stimulation is the degree to which pain is perceived to be controllable. Previous studies indicate that perceived controllability affects pain tolerance, learning and motivation, and the ability to cope with intractable pain, suggesting that it has profound effects on neural pain processing. To date, however, no neuroimaging studies have assessed these effects. We manipulated the subjects' belief that they had control over a nociceptive stimulus, while the stimulus itself was held constant. Using functional magnetic resonance imaging, we found that pain that was perceived to be controllable resulted in attenuated activation in the three neural areas most consistently linked with pain processing: the anterior cingulate, insular, and secondary somatosensory cortices. This suggests that activation at these sites is modulated by cognitive variables, such as perceived controllability, and that pain imaging studies may therefore overestimate the degree to which these responses are stimulus driven and generalizable across cognitive contexts.
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Individuals with fragile X syndrome (FXS) commonly display characteristics of social anxiety, including gaze aversion, increased time to initiate social interaction, and difficulty forming meaningful peer relationships. While neural correlates of face processing, an important component of social interaction, are altered in FXS, studies have not examined whether social anxiety in this population is related to higher cognitive processes, such as memory. This study aimed to determine whether the neural circuitry involved in face encoding was disrupted in individuals with FXS, and whether brain activity during face encoding was related to levels of social anxiety. A group of 11 individuals with FXS (5 M) and 11 age- and gender-matched control participants underwent fMRI scanning while performing a face encoding task with online eye-tracking. Results indicate that compared to the control group, individuals with FXS exhibited decreased activation of prefrontal regions associated with complex social cognition, including the medial and superior frontal cortex, during successful face encoding. Further, the FXS and control groups showed significantly different relationships between measures of social anxiety (including gaze-fixation) and brain activity during face encoding. These data indicate that social anxiety in FXS may be related to the inability to successfully recruit higher level social cognition regions during the initial phases of memory formation.
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Readings in the Anthropocene brings together scholars from German Studies and beyond to interpret the German tradition of the last two hundred years from a perspective that is mindful of the challenge posed by the concept of the Anthropocene. This new age of man, unofficially pronounced in 2000, holds that humans are becoming a geological force in shaping the Earth's future. Among the biggest challenges facing our future are climate change, accelerated species loss, and a radical transformation of land use. What are the historical, philosophical, cultural, literary, and artistic responses to this new concept? The essays in this volume bring German culture to bear on what it means to live in the Anthropocene from a historical, ethical, and aesthetic perspective.

Anhedonia, the loss of pleasure or interest in previously rewarding stimuli, is a core feature of major depression. While theorists have argued that anhedonia reflects a reduced capacity to experience pleasure, evidence is mixed as to whether anhedonia is caused by a reduction in hedonic capacity. An alternative explanation is that anhedonia is due to the inability to sustain positive affect across time. Using positive images, we used an emotion regulation task to test whether individuals with depression are unable to sustain activation in neural circuits underlying positive affect and reward. While up-regulating positive affect, depressed individuals failed to sustain nucleus accumbens activity over time compared with controls. This decreased capacity was related to individual differences in self-reported positive affect. Connectivity analyses further implicated the fronto-striatal network in anhedonia. These findings support the hypothesis that anhedonia in depressed patients reflects the inability to sustain engagement of structures involved in positive affect and reward.
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BACKGROUND: Anhedonia, a reduced ability to experience pleasure, is a chief symptom of major depressive disorder and is related to reduced frontostriatal connectivity when attempting to upregulate positive emotion. The present study examined another facet of positive emotion regulation associated with anhedonia-namely, the downregulation of positive affect-and its relation to prefrontal cortex (PFC) activity. METHODS: Neuroimaging data were collected from 27 individuals meeting criteria for major depressive disorder as they attempted to suppress positive emotion during a positive emotion regulation task. Their PFC activation pattern was compared with the PFC activation pattern exhibited by 19 healthy control subjects during the same task. Anhedonia scores were collected at three time points: at baseline (time 1), 8 weeks after time 1 (i.e., time 2), and 6 months after time 1 (i.e., time 3). Prefrontal cortex activity at time 1 was used to predict change in anhedonia over time. Analyses were conducted utilizing hierarchical linear modeling software. RESULTS: Depressed individuals who could not inhibit positive emotion-evinced by reduced right ventrolateral prefrontal cortex activity during attempts to dampen their experience of positive emotion in response to positive visual stimuli-exhibited a steeper anhedonia reduction slope between baseline and 8 weeks of treatment with antidepressant medication (p < .05). Control subjects showed a similar trend between baseline and time 3. CONCLUSIONS: To reduce anhedonia, it may be necessary to teach individuals how to counteract the functioning of an overactive pleasure-dampening prefrontal inhibitory system.
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Recent brain imaging studies using functional magnetic resonance imaging (fMRI) have implicated insula and anterior cingulate cortices in the empathic response to another's pain. However, virtually nothing is known about the impact of the voluntary generation of compassion on this network. To investigate these questions we assessed brain activity using fMRI while novice and expert meditation practitioners generated a loving-kindness-compassion meditation state. To probe affective reactivity, we presented emotional and neutral sounds during the meditation and comparison periods. Our main hypothesis was that the concern for others cultivated during this form of meditation enhances affective processing, in particular in response to sounds of distress, and that this response to emotional sounds is modulated by the degree of meditation training. The presentation of the emotional sounds was associated with increased pupil diameter and activation of limbic regions (insula and cingulate cortices) during meditation (versus rest). During meditation, activation in insula was greater during presentation of negative sounds than positive or neutral sounds in expert than it was in novice meditators. The strength of activation in insula was also associated with self-reported intensity of the meditation for both groups. These results support the role of the limbic circuitry in emotion sharing. The comparison between meditation vs. rest states between experts and novices also showed increased activation in amygdala, right temporo-parietal junction (TPJ), and right posterior superior temporal sulcus (pSTS) in response to all sounds, suggesting, greater detection of the emotional sounds, and enhanced mentation in response to emotional human vocalizations for experts than novices during meditation. Together these data indicate that the mental expertise to cultivate positive emotion alters the activation of circuitries previously linked to empathy and theory of mind in response to emotional stimuli.
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Recent brain imaging studies using functional magnetic resonance imaging (fMRI) have implicated insula and anterior cingulate cortices in the empathic response to another's pain. However, virtually nothing is known about the impact of the voluntary generation of compassion on this network. To investigate these questions we assessed brain activity using fMRI while novice and expert meditation practitioners generated a loving-kindness-compassion meditation state. To probe affective reactivity, we presented emotional and neutral sounds during the meditation and comparison periods. Our main hypothesis was that the concern for others cultivated during this form of meditation enhances affective processing, in particular in response to sounds of distress, and that this response to emotional sounds is modulated by the degree of meditation training. The presentation of the emotional sounds was associated with increased pupil diameter and activation of limbic regions (insula and cingulate cortices) during meditation (versus rest). During meditation, activation in insula was greater during presentation of negative sounds than positive or neutral sounds in expert than it was in novice meditators. The strength of activation in insula was also associated with self-reported intensity of the meditation for both groups. These results support the role of the limbic circuitry in emotion sharing. The comparison between meditation vs. rest states between experts and novices also showed increased activation in amygdala, right temporo-parietal junction (TPJ), and right posterior superior temporal sulcus (pSTS) in response to all sounds, suggesting, greater detection of the emotional sounds, and enhanced mentation in response to emotional human vocalizations for experts than novices during meditation. Together these data indicate that the mental expertise to cultivate positive emotion alters the activation of circuitries previously linked to empathy and theory of mind in response to emotional stimuli.

Recent brain imaging studies using functional magnetic resonance imaging (fMRI) have implicated insula and anterior cingulate cortices in the empathic response to another's pain. However, virtually nothing is known about the impact of the voluntary generation of compassion on this network. To investigate these questions we assessed brain activity using fMRI while novice and expert meditation practitioners generated a loving-kindness-compassion meditation state. To probe affective reactivity, we presented emotional and neutral sounds during the meditation and comparison periods. Our main hypothesis was that the concern for others cultivated during this form of meditation enhances affective processing, in particular in response to sounds of distress, and that this response to emotional sounds is modulated by the degree of meditation training. The presentation of the emotional sounds was associated with increased pupil diameter and activation of limbic regions (insula and cingulate cortices) during meditation (versus rest). During meditation, activation in insula was greater during presentation of negative sounds than positive or neutral sounds in expert than it was in novice meditators. The strength of activation in insula was also associated with self-reported intensity of the meditation for both groups. These results support the role of the limbic circuitry in emotion sharing. The comparison between meditation vs. rest states between experts and novices also showed increased activation in amygdala, right temporo-parietal junction (TPJ), and right posterior superior temporal sulcus (pSTS) in response to all sounds, suggesting, greater detection of the emotional sounds, and enhanced mentation in response to emotional human vocalizations for experts than novices during meditation. Together these data indicate that the mental expertise to cultivate positive emotion alters the activation of circuitries previously linked to empathy and theory of mind in response to emotional stimuli.

OBJECTIVE Deficits in positive affect and their neural bases have been associated with major depression. However, whether reductions in positive affect result solely from an overall reduction in nucleus accumbens activity and fronto-striatal connectivity or the additional inability to sustain engagement of this network over time is unknown. The authors sought to determine whether treatment-induced changes in the ability to sustain nucleus accumbens activity and fronto-striatal connectivity during the regulation of positive affect are associated with gains in positive affect. METHOD Using fMRI, the authors assessed the ability to sustain activity in reward-related networks when attempting to increase positive emotion during performance of an emotion regulation paradigm in 21 depressed patients before and after 2 months of antidepressant treatment. Over the same interval, 14 healthy comparison subjects underwent scanning as well. RESULTS After 2 months of treatment, self-reported positive affect increased. The patients who demonstrated the largest increases in sustained nucleus accumbens activity over the 2 months were those who demonstrated the largest increases in positive affect. In addition, the patients who demonstrated the largest increases in sustained fronto-striatal connectivity were also those who demonstrated the largest increases in positive affect when controlling for negative affect. None of these associations were observed in healthy comparison subjects. CONCLUSIONS Treatment-induced change in the sustained engagement of fronto-striatal circuitry tracks the experience of positive emotion in daily life. Studies examining reduced positive affect in a variety of psychiatric disorders might benefit from examining the temporal dynamics of brain activity when attempting to understand changes in daily positive affect.
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OBJECTIVE Deficits in positive affect and their neural bases have been associated with major depression. However, whether reductions in positive affect result solely from an overall reduction in nucleus accumbens activity and fronto-striatal connectivity or the additional inability to sustain engagement of this network over time is unknown. The authors sought to determine whether treatment-induced changes in the ability to sustain nucleus accumbens activity and fronto-striatal connectivity during the regulation of positive affect are associated with gains in positive affect. METHOD Using fMRI, the authors assessed the ability to sustain activity in reward-related networks when attempting to increase positive emotion during performance of an emotion regulation paradigm in 21 depressed patients before and after 2 months of antidepressant treatment. Over the same interval, 14 healthy comparison subjects underwent scanning as well. RESULTS After 2 months of treatment, self-reported positive affect increased. The patients who demonstrated the largest increases in sustained nucleus accumbens activity over the 2 months were those who demonstrated the largest increases in positive affect. In addition, the patients who demonstrated the largest increases in sustained fronto-striatal connectivity were also those who demonstrated the largest increases in positive affect when controlling for negative affect. None of these associations were observed in healthy comparison subjects. CONCLUSIONS Treatment-induced change in the sustained engagement of fronto-striatal circuitry tracks the experience of positive emotion in daily life. Studies examining reduced positive affect in a variety of psychiatric disorders might benefit from examining the temporal dynamics of brain activity when attempting to understand changes in daily positive affect.

Subtle-body practices are found particularly in Indian, Indo-Tibetan and East Asian societies, but have become increasingly familiar in Western societies, especially through the various healing and yogic techniques and exercises associated with them. This book explores subtle-body practices from a variety of perspectives, and includes both studies of these practices in Asian and Western contexts. The book discusses how subtle-body practices assume a quasi-material level of human existence that is intermediate between conventional concepts of body and mind. Often, this level is conceived of in terms of an invisible structure of channels, associated with the human body, through which flows of quasi-material substance take place. Contributors look at how subtle-body concepts form the basic explanatory structure for a wide range of practices. These include forms of healing, modes of exercise and martial arts as well as religious practices aimed at the refinement and transformation of the human mindbody complex. By highlighting how subtle-body practices of many kinds have been introduced into Western societies in recent years, the book explores the possibilities for new models of understanding which these concepts open up. It is a useful contribution to studies on Asian Religion and Philosophy.

Subtle-body practices are found particularly in Indian, Indo-Tibetan and East Asian societies, but have become increasingly familiar in Western societies, especially through the various healing and yogic techniques and exercises associated with them. This book explores subtle-body practices from a variety of perspectives, and includes both studies of these practices in Asian and Western contexts. The book discusses how subtle-body practices assume a quasi-material level of human existence that is intermediate between conventional concepts of body and mind. Often, this level is conceived of in terms of an invisible structure of channels, associated with the human body, through which flows of quasi-material substance take place. Contributors look at how subtle-body concepts form the basic explanatory structure for a wide range of practices. These include forms of healing, modes of exercise and martial arts as well as religious practices aimed at the refinement and transformation of the human mindbody complex. By highlighting how subtle-body practices of many kinds have been introduced into Western societies in recent years, the book explores the possibilities for new models of understanding which these concepts open up. It is a useful contribution to studies on Asian Religion and Philosophy.

Subtle-body practices are found particularly in Indian, Indo-Tibetan and East Asian societies, but have become increasingly familiar in Western societies, especially through the various healing and yogic techniques and exercises associated with them. This book explores subtle-body practices from a variety of perspectives, and includes both studies of these practices in Asian and Western contexts. The book discusses how subtle-body practices assume a quasi-material level of human existence that is intermediate between conventional concepts of body and mind. Often, this level is conceived of in terms of an invisible structure of channels, associated with the human body, through which flows of quasi-material substance take place. Contributors look at how subtle-body concepts form the basic explanatory structure for a wide range of practices. These include forms of healing, modes of exercise and martial arts as well as religious practices aimed at the refinement and transformation of the human mindbody complex. By highlighting how subtle-body practices of many kinds have been introduced into Western societies in recent years, the book explores the possibilities for new models of understanding which these concepts open up. It is a useful contribution to studies on Asian Religion and Philosophy.--Publisher website.

Adolescents are in a high-risk period developmentally, in terms of susceptibility to stress. A mindfulness intervention represents a potentially useful strategy for developing cognitive and emotion regulation skills associated with successful stress coping. Mindfulness strategies have been used successfully for emotional coping in adults, but are not as well studied in youth. This article details a novel proposal for the design of an 8-week randomized study to evaluate a high school-based mindfulness curriculum delivered as part of a two semester health class. A wellness education intervention is proposed as an active control, along with a waitlist control condition. All students enrolled in a sophomore (10th grade) health class at a private suburban high school will be invited to participate (n = 300). Pre-test assessments will be obtained by youth report, parent ratings, and on-site behavioral testing. The assessments will evaluate baseline stress, mood, emotional coping, controlled attention, and working memory. Participants, divided into 13 classrooms, will be randomized into one of three conditions, by classroom: A mindfulness intervention, an active control (wellness education), and a passive control (waitlist). Waitlisted participants will receive one of the interventions in the following term. Intervention groups will meet weekly for 8 weeks during regularly scheduled health classes. Immediate post-tests will be conducted, followed by a 60-day post-test. It is hypothesized that the mindfulness intervention will outperform the other conditions with regard to the adolescents' mood, attention and response to stress.

Adolescents are in a high-risk period developmentally, in terms of susceptibility to stress. A mindfulness intervention represents a potentially useful strategy for developing cognitive and emotion regulation skills associated with successful stress coping. Mindfulness strategies have been used successfully for emotional coping in adults, but are not as well studied in youth. This article details a novel proposal for the design of an 8-week randomized study to evaluate a high school-based mindfulness curriculum delivered as part of a two semester health class. A wellness education intervention is proposed as an active control, along with a waitlist control condition. All students enrolled in a sophomore (10th grade) health class at a private suburban high school will be invited to participate (n = 300). Pre-test assessments will be obtained by youth report, parent ratings, and on-site behavioral testing. The assessments will evaluate baseline stress, mood, emotional coping, controlled attention, and working memory. Participants, divided into 13 classrooms, will be randomized into one of three conditions, by classroom: A mindfulness intervention, an active control (wellness education), and a passive control (waitlist). Waitlisted participants will receive one of the interventions in the following term. Intervention groups will meet weekly for 8 weeks during regularly scheduled health classes. Immediate post-tests will be conducted, followed by a 60-day post-test. It is hypothesized that the mindfulness intervention will outperform the other conditions with regard to the adolescents' mood, attention and response to stress.

That the religious ideas of any epoch tend to flow in the channels dug by the philosophy then prevailing is a commonplace, and it is not surprising, therefore, that in the period between the composition of the Kaṭha Upaniṣad and that of the SK. the various religions which are described in more or less detail in the Upaniṣads and the MBh. are for the most part strongly impregnated with Sāṁkhya doctrines. Not that they accepted the Sāṁkhya scheme wholesale; they accept only so much as is necessary for their purposes and have no hesitation in making modifications or discordant additions of their own. Nevertheless we can discern through the confused welter of systems that the general outlines of the scheme set out by Īśvarakṛṣṇa with its summing up of existence under twenty-five heads were accepted as the standard throughout the period. But how disturbing it would be to all our convictions of historical development if, as has been held, not merely was the outer façade of the Sāṁkhya philosophy maintained intact for all that time, but also there was no change inside. In a lapse of many centuries, during which philosophical speculation was so active and new schools with new ideas and methods were developing, we should expect some change in nomenclature and a great deal of change in the conceptions underlying the apparently unchanging scheme; but there is no general agreement yet about the nature and extent of such changes, if any. Partly, the quality of the evidence is to blame; for we have no exposition of Sāṁkhya teaching which is both certainly authoritative and certainly older than the SK., so that a way is always left open to the retort, when a view other than that contained in the SK.

We used fMRI to examine amygdala activation in response to fearful facial expressions, measured over multiple scanning sessions. 15 human subjects underwent three scanning sessions, at 0, 2 and 8 weeks. During each session, functional brain images centered about the amygdala were acquired continuously while participants were shown alternating blocks of fearful, neutral and happy facial expressions. Intraclass correlation coefficients calculated across the sessions indicated stability of response in left amygdala to fearful faces (as a change from baseline), but considerably less left amygdala stability in responses to neutral expressions and for fear versus neutral contrasts. The results demonstrate that the measurement of fMRI BOLD responses in amygdala to fearful facial expressions might be usefully employed as an index of amygdala reactivity over extended periods. While signal change to fearful facial expressions appears robust, the experimental design employed here has yielded variable responsivity within baseline or comparison conditions. Future studies might manipulate the experimental design to either amplify or attenuate this variability, according to the goals of the research.
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This chapter sets out two arguments. My argument in relation to the fi rst issue is that while there are subtle aspects in Tibetan medical concepts of the body, we need to be careful in talking about a separate entity of a ‘subtle body’ as such. My second argument is more preliminary in nature and suggests that Tibetan medical ‘circulatory systems’ or ‘circulatory channels’ do not necessarily move in circulation in the Western sense of the term, and therefore such terms, both in themselves or as translations of Tibetan medical terms, should be used more cautiously.

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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