Although there are many imaging studies on traditional ROI-based amygdala volumetry, there are very few studies on modeling amygdala shape variations. This paper presents a unified computational and statistical framework for modeling amygdala shape variations in a clinical population. The weighted spherical harmonic representation is used to parameterize, smooth out, and normalize amygdala surfaces. The representation is subsequently used as an input for multivariate linear models accounting for nuisance covariates such as age and brain size difference using the SurfStat package that completely avoids the complexity of specifying design matrices. The methodology has been applied for quantifying abnormal local amygdala shape variations in 22 high functioning autistic subjects.
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According to the Conceptual Act Theory of Emotion, the situated conceptualization used to construe a situation determines the emotion experienced. A neuroimaging experiment tested two core hypotheses of this theory: (1) different situated conceptualizations produce different forms of the same emotion in different situations, (2) the composition of a situated conceptualization emerges from shared multimodal circuitry distributed across the brain that produces emotional states generally. To test these hypotheses, the situation in which participants experienced an emotion was manipulated. On each trial, participants immersed themselves in a physical danger or social evaluation situation and then experienced fear or anger. According to Hypothesis 1, the brain activations for the same emotion should differ as a function of the preceding situation (after removing activations that arose while constructing the situation). According to Hypothesis 2, the critical activations should reflect conceptual processing relevant to the emotion in the current situation, drawn from shared multimodal circuitry underlying emotion. The results supported these predictions and demonstrated the compositional process that produces situated conceptualizations dynamically.
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<p>Several recent studies using functional magnetic resonance imaging (fMRI) during recognition memory tests have suggested that the ability to neuromodulate as a function of cognitive demand may be impaired in older adults due to age-related cell loss and neural volume reduction in memory specific regions. In the current study, older adults (ages 59-77) were tested with fMRI during a delayed-recognition task in which memory load for faces was varied across trials. Activity was greater in amplitude for three- versus one-face stimuli within the superior, middle, and inferior frontal gyri, intraparietal sulcus, and fusiform gyrus. It was concluded that the ability to modulate activity with increasing load is preserved in older adults despite reductions in neural volume.</p>
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Few complementary and alternative medicine (CAM) institutions require their students to undergo substantive training in research literacy and conduct, and well-developed programs to train CAM institution faculty in research are virtually non-existent. As part of a National Center for Complementary and Alternative Medicine (NCCAM) initiative to increase research capacity at CAM institutions, the New England School of Acupuncture (NESA), in collaboration with the Harvard Medical School (HMS) Osher Institute, was awarded a Developmental Center for Research on Complementary and Alternative Medicine (DCRC) grant. This article discusses a number of initiatives that we designed and implemented to train NESA students, faculty members, and alumni in the foundations of clinical research and to stimulate interest in both participating in research and receiving additional research training. Specific initiatives included a 30-hour faculty "Foundations of Research" course; a year-long course entitled, "How to Write a Publishable Case Report"; institution of a monthly research seminar series; revision of an already required student research course; and the addition of 2 new student-mentored independent research electives. We discuss successes and challenges encountered in developing and administering these initiatives and the overall impact they have had on research culture and productivity at NESA.
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Using functional magnetic resonance imaging, we examined whether individual differences in amygdala activation in response to negative relative to neutral information are related to differences in the speed with which such information is evaluated, the extent to which such differences are associated with medial prefrontal cortex function, and their relationship with measures of trait anxiety and psychological well-being (PWB). Results indicated that faster judgments of negative relative to neutral information were associated with increased left and right amygdala activation. In the prefrontal cortex, faster judgment time was associated with relative decreased activation in a cluster in the ventral anterior cingulate cortex (ACC, BA 24). Furthermore, people who were slower to evaluate negative versus neutral information reported higher PWB. Importantly, higher PWB was strongly associated with increased activation in the ventral ACC for negative relative to neutral information. Individual differences in trait anxiety did not predict variation in judgment time or in amygdala or ventral ACC activity. These findings suggest that people high in PWB effectively recruit the ventral ACC when confronted with potentially aversive stimuli, manifest reduced activity in subcortical regions such as the amygdala, and appraise such information as less salient as reflected in slower evaluative speed.
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<p>We conducted two fMRI studies to investigate the sensitivity of delay-period activity to changes in memory load during a delayed-recognition task for faces. In Experiment 1, each trial began with the presentation of a memory array consisting of one, two, or three faces that lasted for 3 sec. A 15-sec delay period followed during which no stimuli were present. The delay interval concluded with a one-face probe to which subjects made a button press response indicating whether this face was part of the memory array. Experiment 2 was similar in design except that the delay period was lengthened to 24 sec, and the memory array consisted of only one or three faces. We hypothesized that memory maintenance processes that spanned the delay interval would be revealed by their sensitivity to memory load. Long delay intervals were employed to temporally dissociate phasic activity engendered by the memory array from sustained activity reflecting maintenance. Regions of interest (ROIs) were defined anatomically for the superior frontal gyri (SFG), middle frontal gyri (MFG), and inferior frontal gyri (IFG), intraparietal sulci (IPS), and fusiform gyri (FFG) on a subject-by-subject basis. The mean time course of activity was determined for all voxels within these regions and for that subset of voxels within each ROI that correlated significantly with an empirically determined reference waveform. In both experiments, memory load significantly influenced activation 6--9 sec following the onset of the memory array with larger amplitude responses for higher load levels. Responses were greatest within MFG, IPS, and FFG. In both experiments, however, these load-sensitive differences declined over successive time intervals and were no longer significant at the end of the delay interval. Although insensitive to our load manipulation, sustained activation was present at the conclusion of the delay interval within MFG and other prefrontal regions. IPS delay activity returned to prestimulus baseline levels prior to the end of the delay period in Experiment 2, but not in Experiment 1. Within FFG, delay activity returned to prestimulus baseline levels prior to the conclusion of the delay interval in both experiments. Thus, while phasic processes engendered by the memory array were strongly affected by memory load, no evidence for load-sensitive delay-spanning maintenance processes was obtained.</p>
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As the field of psychology continues to expand and evolve, one fruitful avenue of exploration has been the integration of mindfulness into psychological theory and practice. Mindfulness is defined as the awareness that arises out of intentionally attending in an open and discerning way to whatever is arising in the present moment. Two decades of empirical research have generated considerable evidence supporting the efficacy of mindfulness-based interventions across a wide range of clinical and nonclinical populations, and these interventions have been incorporated into a variety of health care settings. Still, there are many unanswered questions and potential horizons to be investigated. This special issue endeavors to assist in this exploration. It presents a combination of articles concerning aspects of clinical and scientific integration of mindfulness within psychotherapy and psychoeducational settings. This commentary attempts to highlight the main findings of the featured articles as well as elucidate areas for future inquiry. Taken as a whole, the volume supports the importance and viability of the integration of mindfulness into psychology, and offers interesting and meaningful directions for future research.
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Based on previous findings in humans and rhesus monkeys suggesting that diazepam has asymmetrical effects on frontal lobe activity and other literature supporting a role for the benzodiazepine system in the mediation of individual differences in anxiety and fearfulness, the relation between asymmetrical changes in scalp-recorded regional brain activity in response to diazepam and the temperamental dimension of behavioral inhibition indexed by freezing time in 9 rhesus monkeys was examined. Animals showed greater relative left-sided frontal activation in response to diazepam compared with the preceding baseline. The magnitude of this shift was strongly correlated with an aggregate measure of freezing time (r = .82). The implications of these findings for understanding the role of regional differences in the benzodiazepine system in mediating individual differences in fearfulness are discussed.
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Separate, extended series of positive, negative, and neutral pictures were presented to 24 (12 men, 12 women) undergraduates. Each series was presented on a different day, with full counterbalancing of presentation orders. Affective state was measured using (a) orbicularis oculi activity in response to acoustic startle probes during picture presentation, (b) corrugator supercilii activity between and during picture presentation, and (c) changes in self-reports of positive and negative affect. Participants exhibited larger eyeblink reflex magnitudes when viewing negative than when viewing positive pictures. Corrugator activity was also greater during the negative than during the positive picture set, during both picture presentation and the period between pictures. Self-reports of negative affect increased in response to the negative picture set, and self-reports of positive affect were greatest following the positive picture set. These findings suggest that extended picture presentation is an effective method of manipulating affective state and further highlight the utility of startle probe and facial electromyographic measures in providing on-line readouts of affective state.
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A chief goal of this research was to determine whether stimuli and events known to enhance smoking motivation also influence a physiological variable with the potential to index approach motivation. Asymmetry of electroencephalographic (EEG) activity across the frontal regions of the 2 hemispheres (left minus right hemisphere activation) was used to index approach motivation. In theory, if EEG asymmetry sensitively indexes approach dispositions, it should be influenced by manipulations known to affect smoking motivation, that is, exposure to smoking cues and tobacco deprivation. Seventy-two smokers participated in this research and were selectively exposed to a smoking-anticipation condition (cigarettes plus expectation of imminent smoking) following either 24 hr of tobacco withdrawal or ad libitum smoking. Results indicated that EEG asymmetry was increased by smoking anticipation and that smoking itself reduced EEG asymmetry. Results also suggested that smoking anticipation increased overall (bihemispheric) EEG activation. Results were interpreted in terms of major theories of drug motivation.
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In order to gain a deeper understanding of the mindfulness construct and the mental health benefits associated with mindfulness-based programmes, the relation between mindfulness and its proposed core component attention was studied. Buddhist and Western mindfulness meditators were compared with non-meditators on tasks of sustained (SART) and executive (the Stroop Task) attention. Relations between self-reported mindfulness (FFMQ) and sustained and executive attention were also analysed. No significant differences were found between meditators and non-meditators either in sustained or executive attention. High scores on the FFMQ total scale and on Describe were related to fewer SART errors. High scores on Describe were also related to low Stroop interference. Mindfulness meditators may have an increased awareness of internal processes and the ability to quickly attend to them but this type of refined attentional ability does not seem to be related to performance on attention tests requiring responses to external targets.
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The capacity to stabilize the content of attention over time varies among individuals, and its impairment is a hallmark of several mental illnesses. Impairments in sustained attention in patients with attention disorders have been associated with increased trial-to-trial variability in reaction time and event-related potential deficits during attention tasks. At present, it is unclear whether the ability to sustain attention and its underlying brain circuitry are transformable through training. Here, we show, with dichotic listening task performance and electroencephalography, that training attention, as cultivated by meditation, can improve the ability to sustain attention. Three months of intensive meditation training reduced variability in attentional processing of target tones, as indicated by both enhanced theta-band phase consistency of oscillatory neural responses over anterior brain areas and reduced reaction time variability. Furthermore, those individuals who showed the greatest increase in neural response consistency showed the largest decrease in behavioral response variability. Notably, we also observed reduced variability in neural processing, in particular in low-frequency bands, regardless of whether the deviant tone was attended or unattended. Focused attention meditation may thus affect both distracter and target processing, perhaps by enhancing entrainment of neuronal oscillations to sensory input rhythms, a mechanism important for controlling the content of attention. These novel findings highlight the mechanisms underlying focused attention meditation and support the notion that mental training can significantly affect attention and brain function.
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A growing body of evidence suggests that empathy for pain is underpinned by neural structures that are also involved in the direct experience of pain. In order to assess the consistency of this finding, an image-based meta-analysis of nine independent functional magnetic resonance imaging (fMRI) investigations and a coordinate-based meta-analysis of 32 studies that had investigated empathy for pain using fMRI were conducted. The results indicate that a core network consisting of bilateral anterior insular cortex and medial/anterior cingulate cortex is associated with empathy for pain. Activation in these areas overlaps with activation during directly experienced pain, and we link their involvement to representing global feeling states and the guidance of adaptive behavior for both self- and other-related experiences. Moreover, the image-based analysis demonstrates that depending on the type of experimental paradigm this core network was co-activated with distinct brain regions: While viewing pictures of body parts in painful situations recruited areas underpinning action understanding (inferior parietal/ventral premotor cortices) to a stronger extent, eliciting empathy by means of abstract visual information about the other's affective state more strongly engaged areas associated with inferring and representing mental states of self and other (precuneus, ventral medial prefrontal cortex, superior temporal cortex, and temporo-parietal junction). In addition, only the picture-based paradigms activated somatosensory areas, indicating that previous discrepancies concerning somatosensory activity during empathy for pain might have resulted from differences in experimental paradigms. We conclude that social neuroscience paradigms provide reliable and accurate insights into complex social phenomena such as empathy and that meta-analyses of previous studies are a valuable tool in this endeavor.
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BACKGROUND: Many antidepressant medications (ADM) are associated with disruptions in sleep continuity that can compromise medication adherence and impede successful treatment. The present study investigated whether mindfulness meditation (MM) training could improve self-reported and objectively measured polysomnographic (PSG) sleep profiles in depressed individuals who had achieved at least partial remission with ADM, but still had residual sleep complaints.
METHODS: Twenty-three ADM users with sleep complaints were randomized into an 8-week Mindfulness-Based Cognitive Therapy (MBCT) course or a waitlist control condition. Pre-post measurements included PSG sleep studies and subjectively reported sleep, residual depression symptoms.
RESULTS: Compared to controls, the MBCT participants improved on both PSG and subjective measures of sleep. They showed a pattern of decreased wake time and increased sleep efficiency. Sleep depth, as measured by stage 1 and slow-wave sleep, did not change as a result of mindfulness training.
CONCLUSIONS: MM is associated with increases in both objectively and subjectively measured sleep continuity in ADM users. MM training may serve as more desirable and cost-effective alternative to discontinuation or supplementation with hypnotics, and may contribute to a more sustainable recovery from depression.
<p>BACKGROUND: Many antidepressant medications (ADM) are associated with disruptions in sleep continuity that can compromise medication adherence and impede successful treatment. The present study investigated whether mindfulness meditation (MM) training could improve self-reported and objectively measured polysomnographic (PSG) sleep profiles in depressed individuals who had achieved at least partial remission with ADM, but still had residual sleep complaints. METHODS: Twenty-three ADM users with sleep complaints were randomized into an 8-week Mindfulness-Based Cognitive Therapy (MBCT) course or a waitlist control condition. Pre-post measurements included PSG sleep studies and subjectively reported sleep, residual depression symptoms. RESULTS: Compared to controls, the MBCT participants improved on both PSG and subjective measures of sleep. They showed a pattern of decreased wake time and increased sleep efficiency. Sleep depth, as measured by stage 1 and slow-wave sleep, did not change as a result of mindfulness training. CONCLUSIONS: MM is associated with increases in both objectively and subjectively measured sleep continuity in ADM users. MM training may serve as more desirable and cost-effective alternative to discontinuation or supplementation with hypnotics, and may contribute to a more sustainable recovery from depression.</p>
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Objective: Mindfulness-based stress reduction (MBSR) is a structured group program that employs mindfulness meditation to alleviate suffering associated with physical, psychosomatic and psychiatric disorders. The program, nonreligious and nonesoteric, is based upon a systematic procedure to develop enhanced awareness of moment-to-moment experience of perceptible mental processes. The approach assumes that greater awareness will provide more veridical perception, reduce negative affect and improve vitality and coping. In the last two decades, a number of research reports appeared that seem to support many of these claims. We performed a comprehensive review and meta-analysis of published and unpublished studies of health-related studies related to MBSR. Methods: Sixty-four empirical studies were found, but only 20 reports met criteria of acceptable quality or relevance to be included in the meta-analysis. Reports were excluded due to (I) insufficient information about interventions, (2) poor quantitative health evaluation, (3) inadequate statistical analysis, (4) mindfulness not being the central component of intervention, or (5) the setting of intervention or sample composition deviating too widely from the health-related MBSR program. Acceptable studies covered a wide spectrum of clinical populations (e.g., pain, cancer, heart disease, depression, and anxiety), as well as stressed nonclinical groups. Both controlled and observational investigations were included. Standardized measures of physical and mental well-being constituted the dependent variables of the analysis. Results: Overall, both controlled and uncontrolled studies showed similar effect sizes of approximately 0.5 (P <.0001) with homogeneity of distribution. Conclusion: Although derived from a relatively small number of studies, these results suggest that MBSR may help a broad range of individuals to cope with their clinical and nonclinical problems.
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OBJECTIVES: The objectives of this study were to assess the general acceptability and to assess domains of potential effect of a mindfulness-based stress reduction (MBSR) program for human immunodeficiency virus (HIV)-infected and at-risk urban youth.
METHODS: Thirteen-to twenty-one-year-old youth were recruited from the pediatric primary care clinic of an urban tertiary care hospital to participate in 4 MBSR groups. Each MBSR group consisted of nine weekly sessions of MBSR instruction. This mixed-methods evaluation consisted of quantitative data--attendance, psychologic symptoms (Symptom Checklist 90-Revised), and quality of life (Child Health and Illness Profile-Adolescent Edition)--and qualitative data--in-depth individual interviews conducted in a convenience sample of participants until interview themes were saturated. Analysis involved comparison of pre- and postintervention surveys and content analysis of interviews.
RESULTS: Thirty-three (33) youth attended at least one MBSR session. Of the 33 who attended any sessions, 26 youth (79%) attended the majority of the MBSR sessions and were considered "program completers." Among program completers, 11 were HIV-infected, 77% were female, all were African American, and the average age was 16.8 years. Quantitative data show that following the MBSR program, participants had a significant reduction in hostility (p = 0.02), general discomfort (p = 0.01), and emotional discomfort (p = 0.02). Qualitative data (n = 10) show perceived improvements in interpersonal relationships (including less conflict), school achievement, physical health, and reduced stress.
CONCLUSIONS: The data suggest that MBSR instruction for urban youth may have a positive effect in domains related to hostility, interpersonal relationships, school achievement, and physical health. However, because of the small sample size and lack of control group, it cannot be distinguished whether the changes observed are due to MBSR or to nonspecific group effects. Further controlled trials should include assessment of the MBSR program's efficacy in these domains.
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OBJECTIVES: This study investigated the relationships between a mindfulness-based stress reduction meditation program for early stage breast and prostate cancer patients and quality of life, mood states, stress symptoms, lymphocyte counts, and cytokine production.
METHODS: Forty-nine patients with breast cancer and 10 with prostate cancer participated in an 8-week MBSR program that incorporated relaxation, meditation, gentle yoga, and daily home practice. Demographic and health behavior variables, quality of life (EORTC QLQ C-30), mood (POMS), stress (SOSI), and counts of NK, NKT, B, T total, T helper, and T cytotoxic cells, as well as NK and T cell production of TNF, IFN-γ, IL-4, and IL-10 were assessed pre- and postintervention.
RESULTS: Fifty-nine and 42 patients were assessed pre- and postintervention, respectively. Significant improvements were seen in overall quality of life, symptoms of stress, and sleep quality. Although there were no significant changes in the overall number of lymphocytes or cell subsets, T cell production of IL-4 increased and IFN-γ decreased, whereas NK cell production of IL-10 decreased. These results are consistent with a shift in immune profile from one associated with depressive symptoms to a more normal profile.
CONCLUSIONS: MBSR participation was associated with enhanced quality of life and decreased stress symptoms in breast and prostate cancer patients. This study is also the first to show changes in cancer-related cytokine production associated with program participation.
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Although research has found that long-term mindfulness meditation practice promotes executive functioning and the ability to sustain attention, the effects of brief mindfulness meditation training have not been fully explored. We examined whether brief meditation training affects cognition and mood when compared to an active control group. After four sessions of either meditation training or listening to a recorded book, participants with no prior meditation experience were assessed with measures of mood, verbal fluency, visual coding, and working memory. Both interventions were effective at improving mood but only brief meditation training reduced fatigue, anxiety, and increased mindfulness. Moreover, brief mindfulness training significantly improved visuo-spatial processing, working memory, and executive functioning. Our findings suggest that 4 days of meditation training can enhance the ability to sustain attention; benefits that have previously been reported with long-term meditators.
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Mindfulness-based interventions have been shown to alleviate symptoms of a wide range of physical and mental health conditions. Regular between-session practice of mindfulness meditation is among the key factors proposed to produce the therapeutic benefits of mindfulness-based programs. This article reviews the mindfulness intervention literature with a focus on the status of home practice research and the relationship of practice to mindfulness program outcomes. Of 98 studies reviewed, nearly one-quarter (N = 24) evaluated the associations between home practice and measures of clinical functioning, with just over half (N = 13) demonstrating at least partial support for the benefits of practice. These findings indicate a substantial disparity between what is espoused clinically and what is known empirically about the benefits of mindfulness practice. Improved methodologies for tracking and evaluating the effects of home practice are recommended.
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<p>Mindfulness refers to a set of practices as well as the psychological state and trait produced by such practices. The state, trait, and practice of mindfulness may be broadly characterized by a present-oriented, nonjudgmental awareness of cognitions, emotions, sensations, and perceptions without fixation on thoughts of past or future. Research on mindfulness has proliferated over the past decade. Given the explosion of scientific interest in this topic, mindfulness-based therapies are attracting the attention of clinical social workers, who seek to implement these interventions in numerous practice settings. Concomitantly, research on mindfulness is now falling within the scope and purview of social work scholars. In response to the growing interest in mindfulness within academic social work, the present article outlines six conceptual and methodological recommendations for the conduct of future empirical studies on mindfulness. These recommendations have practical importance for advancing mindfulness research within and beyond social work.</p>
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