It is the central hypothesis of this paper that the mental states commonly referred to as altered states of consciousness are principally due to transient prefrontal cortex deregulation. Supportive evidence from psychological and neuroscientific studies of dreaming, endurance running, meditation, daydreaming, hypnosis, and various drug-induced states is presented and integrated. It is proposed that transient hypofrontality is the unifying feature of all altered states and that the phenomenological uniqueness of each state is the result of the differential viability of various frontal circuits. Using an evolutionary approach, consciousness is conceptualized as hierarchically ordered cognitive function. Higher-order structures perform increasingly integrative functions and thus contribute more sophisticated content. Although this implies a holistic approach to consciousness, such a functional hierarchy localizes the most sophisticated layers of consciousness in the zenithal higher-order structure: the prefrontal cortex. The hallmark of altered states of consciousness is the subtle modification of behavioral and cognitive functions that are typically ascribed to the prefrontal cortex. The theoretical framework presented yields a number of testable hypotheses.
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<p>In this commentary I discuss the integration of mindful procedures in cognitive therapy of generalized anxiety disorder (CAD) and attempt to answer questions concerning the effects of mindfulness on information processing and on mechanisms purported to maintain CAD in the meta-cognitive model of this disorder. Different techniques that promote mindfulness can be identified, including mindfulness meditation and attention training. These techniques are intended to disrupt repetitive styles of dysfunctional thinking. I argue that the effect of mindfulness strategies on information processing in emotional disorder can be conceptualized in meta-cognitive terms as (a) activating a meta-cognitive mode of processing; (b) disconnecting the influence of maladaptive beliefs on processing; (c) strengthening flexible responding to threat; and (d) strengthening meta-cognitive plans for controlling cognition. Although mindfulness meditation may have general treatment applications, the meta-cognitive model of CAD suggests caution in using this treatment in CAD. It is unclear which dimension of worry should be targeted, and mindfulness meditation does not contain information that can lead to unambiguous disconfirmation of erroneous beliefs about worry.</p>
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BACKGROUND: The broad autism phenotype includes subclinical autistic characteristics found to have a higher prevalence in unaffected family members of individuals with autism. These characteristics primarily affect the social aspects of language, communication, and human interaction. The current research focuses on possible neurobehavioral characteristics associated with the broad autism phenotype.
METHODS: We used a face-processing task associated with atypical patterns of gaze fixation and brain function in autism while collecting brain functional magnetic resonance imaging (fMRI) and eye tracking in unaffected siblings of individuals with autism.
RESULTS: We found robust differences in gaze fixation and brain function in response to images of human faces in unaffected siblings compared with typically developing control individuals. The siblings' gaze fixations and brain activation patterns during the face processing task were similar to that of the autism group and showed decreased gaze fixation along with diminished fusiform activation compared with the control group. Furthermore, amygdala volume in the siblings was similar to the autism group and was significantly reduced compared with the control group.
CONCLUSIONS: Together, these findings provide compelling evidence for differences in social/emotional processing and underlying neural circuitry in siblings of individuals with autism, supporting the notion of unique endophenotypes associated with the broad autism phenotype.
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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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The prefrontal cortex (PFC) has been well known for its role in higher order cognition, affect regulation and social reasoning. Although the precise underpinnings have not been sufficiently described, increasing evidence also supports a prefrontal involvement in the regulation of the hypothalamus-pituitary-adrenal (HPA) axis. Here we investigate the PFC's role in HPA axis regulation during a psychosocial stress exposure in 14 healthy humans. Regional brain metabolism was assessed using positron emission tomography (PET) and injection of fluoro-18-deoxyglucose (FDG). Depending on the exact location within the PFC, increased glucose metabolic rate was associated with lower or higher salivary cortisol concentration in response to a psychosocial stress condition. Metabolic glucose rate in the rostral medial PFC (mPFC) (Brodman area (BA) 9 and BA 10) was negatively associated with stress-induced salivary cortisol increases. Furthermore, metabolic glucose rate in these regions was inversely coupled with changes in glucose metabolic rate in other areas, known to be involved in HPA axis regulation such as the amygdala/hippocampal region. In contrast, metabolic glucose rate in areas more lateral to the mPFC was positively associated with saliva cortisol. Subjective ratings on task stressfulness, task controllability and self-reported dispositional mood states also showed positive and negative associations with the glucose metabolic rate in prefrontal regions. These findings suggest that in humans, the PFC is activated in response to psychosocial stress and distinct prefrontal metabolic glucose patterns are linked to endocrine stress measures as well as subjective ratings on task stressfulness, controllability as well as dispositional mood states.
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- Buddhist Contemplation by Applied Subject,
- Contemplation by Applied Subject,
- Contemplation by Tradition,
- Psychotherapy and Buddhist Contemplation,
- Health Care and Buddhist Contemplation,
- Health Care and Contemplation,
- Emotions and Contemplation,
- Psychology and Contemplation,
- Science and Contemplation,
- Buddhist Contemplation
BACKGROUND: Although it has been hypothesized that glucocorticoid hypersecretion in depressed patients leads to neuronal atrophy in the hippocampus, magnetic resonance imaging (MRI) -based morphometry studies of the hippocampus to date have produced mixed results.
METHODS: In our MRI study, hippocampal volumes were measured in 25 depressed patients (13 with melancholia and 12 without melancholia) and 15 control subjects.
RESULTS: No significant differences in hippocampus volumes were found between any of the subject groups, although within subjects right hippocampal volumes were found to be significantly larger than left hippocampal volumes. Additionally, right and total (left + right) hippocampal volumes in control and depressed subjects were found to be positively correlated with trait anxiety as measured by the state/trait anxiety inventory.
CONCLUSIONS: Because our subject group is younger than those in studies reporting hippocampal atrophy, we conclude that longitudinal studies will be necessary for investigation of the lifelong course of hippocampal volumetry.
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Cultivation of mindfulness, the nonjudgmental awareness of experiences in the present moment, produces beneficial effects on well-being and ameliorates psychiatric and stress-related symptoms. Mindfulness meditation has therefore increasingly been incorporated into psychotherapeutic interventions. Although the number of publications in the field has sharply increased over the last two decades, there is a paucity of theoretical reviews that integrate the existing literature into a comprehensive theoretical framework. In this article, we explore several components through which mindfulness meditation exerts its effects: (a) attention regulation, (b) body awareness, (c) emotion regulation (including reappraisal and exposure, extinction, and reconsolidation), and (d) change in perspective on the self. Recent empirical research, including practitioners’ self-reports and experimental data, provides evidence supporting these mechanisms. Functional and structural neuroimaging studies have begun to explore the neuroscientific processes underlying these components. Evidence suggests that mindfulness practice is associated with neuroplastic changes in the anterior cingulate cortex, insula, temporo-parietal junction, fronto-limbic network, and default mode network structures. The authors suggest that the mechanisms described here work synergistically, establishing a process of enhanced self-regulation. Differentiating between these components seems useful to guide future basic research and to specifically target areas of development in the treatment of psychological disorders.
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<p>The mindfulness-based stress reduction (MBSR) program was designed to be long enough for participants to grasp the principles of self-regulation through mindfulness and develop skill and autonomy in mindfulness practice. It traditionally consists of 26 hours of session time including eight classes of 2-1/2 hours and an all-day class. The circumstances of some groups exclude them from participating in this standard form and a number of trials have evaluated programs with abbreviated class time. If lower program time demands can lead to similar outcomes in psychological functioning, it would support their utility in these settings and might lead to greater participation. However, the effect of variation in class hours on outcomes has not been systematically studied. To obtain preliminary information related to this question we examined effect sizes for psychological outcome variables in published studies of MBSR, some of which had adapted the standard number of class hours. The correlation between mean effect size and number of in-class hours was nonsignificant for both clinical and nonclinical samples and suggests that adaptations that include less class time may be worthwhile for populations for whom reduction of psychological distress is an important goal and for whom longer time commitment may be a barrier to their ability or willingness to participate. However, the standard MBSR format has accrued the most empirical support for its efficacy and session time may be important to the development of other kinds of program outcomes. The result points to the importance of empirical studies systematically examining this question. © 2009 Wiley Periodicals, Inc. J Clin Psychol 65: 1–12, 2009.</p>
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Neurosurgical treatment of psychiatric disorders has been influenced by evolving neurobiological models of symptom generation. The advent of functional neuroimaging and advances in the neurosciences have revolutionized understanding of the functional neuroanatomy of psychiatric disorders. This article reviews neuroimaging studies of depression from the last 3 decades and describes an emerging neurocircuitry model of mood disorders, focusing on critical circuits of cognition and emotion, particularly those networks involved in the regulation of evaluative, expressive and experiential aspects of emotion. The relevance of this model for neurotherapeutics is discussed, as well as the role of functional neuroimaging of psychiatric disorders.
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Two hundred and nine pupils were randomly allocated to either a cognitive behaviourally based stress management intervention (SMI) group, or a non-intervention control group. Mood and motivation measures were administered pre and post intervention. Standardized examinations were taken 8–10 weeks later. As hypothesized, results indicated that an increase in the functionality of pupils’ cognitions served as the mechanism by which mental health improved in the SMI group. In contrast, the control group demonstrated no such improvements. Also, as predicted, an increase in motivation accounted for the SMI group's significantly better performance on the standardized, academic assessments that comprise the United Kingdom's General Certificate of Secondary Education. Indeed, the magnitude of this enhanced performance was, on average, one-letter grade. Discussion focuses on the theoretical and practical implications of these findings.
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<p>Cultivating Awareness and Resilience in Education (CARE for Teachers) is a mindfulness-based professional development program designed to reduce stress and improve teachers’ performance and classroom learning environments. A randomized controlled trial examined program efficacy and acceptability among a sample of 50 teachers randomly assigned to CARE or waitlist control condition. Participants completed a battery of self-report measures at pre- and postintervention to assess the impact of the CARE program on general well-being, efficacy, burnout/time pressure, and mindfulness. Participants in the CARE group completed an evaluation of the program after completing the intervention. ANCOVAs were computed between the CARE group and control group for each outcome, and the pretest scores served as a covariate. Participation in the CARE program resulted in significant improvements in teacher well-being, efficacy, burnout/time-related stress, and mindfulness compared with controls. Evaluation data showed that teachers viewed CARE as a feasible, acceptable, and effective method for reducing stress and improving performance. Results suggest that the CARE program has promise to support teachers working in challenging settings and consequently improve classroom environments.</p>
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<p>Cultivating Awareness and Resilience in Education (CARE) is a professional development program designed to reduce stress and improve teachers' performance. Two pilot studies examined program feasibility and attractiveness and preliminary evidence of efficacy. Study 1 involved educators from a high-poverty urban setting (n = 31). Study 2 involved student teachers and 10 of their mentors working in a suburban/semi-rural setting (n = 43) (treatment and control groups). While urban educators showed significant pre-post improvements in mindfulness and time urgency, the other sample did not, suggesting that CARE may be more efficacious in supporting teachers working in high-risk settings. (Contains 2 tables, 1 figure and 1 footnote.)</p>
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Baseline resting electroencephalogram activity was recorded with 3 different reference montages from 15 clinically depressed and 13 control subjects. Power in all frequency bands was extracted by fast Fourier transformation. There was a significant Group X Hemisphere interaction in the mid-frontal region, for the alpha band power only. Depressed subjects had less left-sided activation (i.e., more alpha activity) than did normal control subjects. This pattern of diminished left-sided frontal activation is interpreted as indicating a deficit in approach mechanisms in depressed subjects.
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Social contact promotes enhanced health and well-being, likely as a function of the social regulation of emotional responding in the face of various life stressors. For this functional magnetic resonance imaging (fMRI) study, 16 married women were subjected to the threat of electric shock while holding their husband's hand, the hand of an anonymous male experimenter, or no hand at all. Results indicated a pervasive attenuation of activation in the neural systems supporting emotional and behavioral threat responses when the women held their husband's hand. A more limited attenuation of activation in these systems occurred when they held the hand of a stranger. Most strikingly, the effects of spousal hand-holding on neural threat responses varied as a function of marital quality, with higher marital quality predicting less threat-related neural activation in the right anterior insula, superior frontal gyrus, and hypothalamus during spousal, but not stranger, hand-holding.
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Autism is a neurodevelopmental disorder affecting behavioral and social cognition, but there is little understanding about the link between the functional deficit and its underlying neuroanatomy. We applied a 2D version of voxel-based morphometry (VBM) in differentiating the white matter concentration of the corpus callosum for the group of 16 high functioning autistic and 12 normal subjects. Using the white matter density as an index for neural connectivity, autism is shown to exhibit less white matter concentration in the region of the genu, rostrum, and splenium removing the effect of age based on the general linear model (GLM) framework. Further, it is shown that the less white matter concentration in the corpus callosum in autism is due to hypoplasia rather than atrophy.
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<p>A long-standing problem in stress research has been that individuals' reports of their tendencies to become anxious are often inconsistent with relevant behavioral and physiological indices. This study investigated the distinction between (a) truly low-anxious Ss, who report low trait anxiety on the Taylor Manifest Anxiety Scale and low defensiveness on the Marlowe-Crowne Social Desirability Scale, and (b) repressors, who report low anxiety but high defensiveness. These groups were compared with a moderately high-anxious one. Heart rate, spontaneous skin resistance responses, and forehead muscle tension were recorded from 40 male college students during a phrase association task. Significant differences in the 3 physiological measures as well as in 3 behavioral ones (reaction time, content avoidance, and verbal interference) all indicated that the repressors were more stressed than the low-anxious Ss despite their claims of lower trait anxiety. The high-anxious group exhibited a 3rd pattern suggesting an intermediate level of anxious responding. These data document the need to distinguish between repressors and truly low-anxious persons in research concerned with relations between self-reported anxiety and behavioral and physiological responses to stress. (42 ref)</p>
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INTRODUCTION: Major depressive disorder (MDD) is characterized by cognitive biases in attention, memory and language use. Language use biases often parallel depression symptoms, and contain over-representations of both negative emotive and death words as well as low levels of positive emotive words. This study further explores cognitive biases in depression by comparing the effect of current depression status to cumulative depression history on an elaborated verbal recall of emotional photographs.
METHODS: Following a negative mood induction, fifty-two individuals (42 women) with partially-remitted depression viewed - then recalled and verbally described - slides from the International Affective Picture System (IAPS). Descriptions were transcribed and frequency of depression-related word use (positive emotion, negative emotion, sex, ingestion and death) was analyzed using the Linguistic Inquiry and Word Count program (LIWC).
RESULTS: Contrary to expectations and previous findings, current depression status did not affect word use in any categories of interest. However, individuals with more than 5 years of previous depression used fewer words related to positive emotion (t(50) = 2.10, p = .04, (d = 0.57)), and sex (t(48) = 2.50, p = .013 (d = 0.81)), and there was also a trend for these individuals to use fewer ingestion words (t(50) = 1.95, p = .057 (d = 0.58)), suggesting a deficit in appetitive processing.
CONCLUSIONS: Our findings suggest that depression duration affects appetitive information processing and that appetitive word use may be a behavioral marker for duration related brain changes which may be used to inform treatment.
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Self-conscious emotions such as embarrassment and shame are associated with 2 aspects of theory of mind (ToM): (a) the ability to understand that behavior has social consequences in the eyes of others and (b) an understanding of social norms violations. The present study aimed to link ToM with the recognition of self-conscious emotion. Children with and without autism identified facial expressions conscious of self-conscious and non-self-conscious emotions from photographs. ToM was also measured. Children with autism performed more poorly than comparison children at identifying self-conscious emotions, though they did not differ in the recognition of non-self-conscious emotions. When ToM ability was statistically controlled, group differences in the recognition of self-conscious emotion disappeared. Discussion focused on the links between ToM and self-conscious emotion.
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To better understand the neurobiological mechanisms by which mindfulness-based practices function in a psychotherapeutic context, this article details the definition, techniques, and purposes ascribed to mindfulness training as described by its Buddhist tradition of origin and by contemporary neurocognitive models. Included is theory of how maladaptive mental processes become habitual and automatic, both from the Buddhist and Western psychological perspective. Specific noting and labeling techniques in open monitoring meditation, described in the Theravada and Western contemporary traditions, are highlighted as providing unique access to multiple modalities of awareness. Potential explicit and implicit mechanisms are discussed by which such techniques can contribute to transforming maladaptive habits of mind and perceptual and cognitive biases, improving efficiency, facilitating integration, and providing the flexibility to switch between systems of self-processing. Finally, a model is provided to describe the timing by which noting and labeling practices have the potential to influence different stages of low- and high-level neural processing. Hypotheses are proposed concerning both levels of processing in relation to the extent of practice. Implications for the nature of subjective experience and self-processing as it relates to one's habits of mind, behavior, and relation to the external world, are also described.
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<p>Objective and Participants: The authors evaluated the effects on stress, rumination, forgiveness, and hope of two 8-week, 90-min/wk training programs for college undergraduates in meditation-based stress-management tools. Methods: After a pretest, the authors randomly allocated college undergraduates to training in mindfulness-based stress reduction (MBSR; n = 15), Easwaran's Eight-Point Program (EPP; n = 14), or wait-list control ( n = 15). The authors gathered pretest, posttest, and 8-week follow-up data on self-report outcome measures. Results: The authors observed no post-treatment differences between MBSR and EPP or between posttest and 8-week follow-up ( p > .10). Compared with controls, treated participants ( n = 29) demonstrated significant benefits for stress ( p < .05, Cohen's d = -.45) and forgiveness ( p < .05, d = .34) and marginal benefits for rumination ( p < .10, d = -.34). Conclusions: Evidence suggests that meditation-based stress-management practices reduce stress and enhance forgiveness among college undergraduates. Such programs merit further study as potential health-promotion tools for college populations.</p>
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In this article the author examines the use of meditation as an aid to conventional medicine, examines the increased research on the subject, and offers a critique of Mindfulness-Based Stress Reduction (MBSR), the therapeutic meditation method developed by molecular biologist Jon Kabat-Zinn. A number of topics are addressed including Kabat-Zinn's perception of MBSR as Buddhist meditation without a religious element, the moral framework of yoga and meditation, and the lack of interaction and community in the practice of MBSR.
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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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