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Meditation is a mental training, which involves attention and the ability to maintain focus on a particular object. In this study we have applied a specific attentional task to simply measure the performance of the participants with different levels of meditation experience, rather than evaluating meditation practice per se or task performance during meditation. Our objective was to evaluate the performance of regular meditators and non-meditators during an fMRI adapted Stroop Word-Colour Task (SWCT), which requires attention and impulse control, using a block design paradigm. We selected 20 right-handed regular meditators and 19 non-meditators matched for age, years of education and gender. Participants had to choose the colour (red, blue or green) of single words presented visually in three conditions: congruent, neutral and incongruent. Non-meditators showed greater activity than meditators in the right medial frontal, middle temporal, precentral and postcentral gyri and the lentiform nucleus during the incongruent conditions. No regions were more activated in meditators relative to non-meditators in the same comparison. Non-meditators showed an increased pattern of brain activation relative to regular meditators under the same behavioural performance level. This suggests that meditation training improves efficiency, possibly via improved sustained attention and impulse control.
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Intensive training in Vipassana meditation enhances one's ability to allocate attention efficiently in order to detect visual targets accurately. Behavioral and event-related potential evidence for a causal link between behavioral training and brain plasticity in adults is shown.
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- Classical Buddhist Contemplation Practices,
- Buddhist Contemplation by Applied Subject,
- Contemplation by Applied Subject,
- Contemplation by Tradition,
- Neuroscience and Buddhist Contemplation,
- Science and Buddhist Contemplation,
- Neuroscience and Contemplation,
- Practices of Buddhist Contemplation,
- Insight (vipashyana, lhaktong),
- Science and Contemplation,
- Buddhist Contemplation
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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<p>A leading researcher in brain dysfunction and a "Wall Street Journal" science writer demonstrate that the human mind is an independent entity that can shape and control the physical brain.</p>
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Mindfulness is defined as paying attention in the present moment. We investigate the hypothesis that mindfulness training may alter or enhance specific aspects of attention. We examined three functionally and neuroanatomically distinct but overlapping attentional subsystems: alerting, orienting, and conflict monitoring. Functioning of each subsystem was indexed by performance on the Attention Network Test (ANT; Fan, McCandliss, Sommer, Raz, & Posner, 2002). Two types of mindfulness training (MT) programs were examined, and behavioral testing was conducted on participants before (Time 1) and after (Time 2) training. One training group consisted of individuals naive to mindfulness techniques who participated in an 8-week mindfulness-based stress reduction (MBSR) course that emphasized the development of concentrative meditation skills. The other training group consisted of individuals experienced in concentrative meditation techniques who participated in a 1-month intensive mindfulness retreat. Performance of these groups was compared with that of control participants who were meditation naive and received no MT. At Time 1, the participants in the retreat group demonstrated improved conflict monitoring performance relative to those in the MBSR and control groups. At Time 2, the participants in the MBSR course demonstrated significantly improved orienting in comparison with the control and retreat participants. In contrast, the participants in the retreat group demonstrated altered performance on the alerting component, with improvements in exogenous stimulus detection in comparison with the control and MBSR participants. The groups did not differ in conflict monitoring performance at Time 2. These results suggest that mindfulness training may improve attention-related behavioral responses by enhancing functioning of specific subcomponents of attention. Whereas participation in the MBSR course improved the ability to endogenously orient attention, retreat participation appeared to allow for the development and emergence of receptive attentional skills, which improved exogenous alerting-related process.
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Studies have suggested that the default mode network is active during mind wandering, which is often experienced intermittently during sustained attention tasks. Conversely, an anticorrelated task-positive network is thought to subserve various forms of attentional processing. Understanding how these two systems work together is central for understanding many forms of optimal and sub-optimal task performance. Here we present a basic model of naturalistic cognitive fluctuations between mind wandering and attentional states derived from the practice of focused attention meditation. This model proposes four intervals in a cognitive cycle: mind wandering, awareness of mind wandering, shifting of attention, and sustained attention. People who train in this style of meditation cultivate their abilities to monitor cognitive processes related to attention and distraction, making them well suited to report on these mental events. Fourteen meditation practitioners performed breath-focused meditation while undergoing fMRI scanning. When participants realized their mind had wandered, they pressed a button and returned their focus to the breath. The four intervals above were then constructed around these button presses. We hypothesized that periods of mind wandering would be associated with default mode activity, whereas cognitive processes engaged during awareness of mind wandering, shifting of attention and sustained attention would engage attentional subnetworks. Analyses revealed activity in brain regions associated with the default mode during mind wandering, and in salience network regions during awareness of mind wandering. Elements of the executive network were active during shifting and sustained attention. Furthermore, activations during these cognitive phases were modulated by lifetime meditation experience. These findings support and extend theories about cognitive correlates of distributed brain networks.
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A review of behavioral and neurobiological data on mood and mood regulation as they pertain to an understanding of mood disorders is presented. Four approaches are considered: 1) behavioral and cognitive; 2) neurobiological; 3) computational; and 4) developmental. Within each of these four sections, we summarize the current status of the field and present our vision for the future, including particular challenges and opportunities. We conclude with a series of specific recommendations for National Institute of Mental Health priorities. Recommendations are presented for the behavioral domain, the neural domain, the domain of behavioral-neural interaction, for training, and for dissemination. It is in the domain of behavioral-neural interaction, in particular, that new research is required that brings together traditions that have developed relatively independently. Training interdisciplinary clinical scientists who meaningfully draw upon both behavioral and neuroscientific literatures and methods is critically required for the realization of these goals.
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<p>Empathy—the ability to share the feelings of others—is fundamental to our emotional and social lives. Previous human imaging studies focusing on empathy for others' pain have consistently shown activations in regions also involved in the direct pain experience, particularly anterior insula and anterior and midcingulate cortex. These findings suggest that empathy is, in part, based on shared representations for firsthand and vicarious experiences of affective states. Empathic responses are not static but can be modulated by person characteristics, such as degree of alexithymia. It has also been shown that contextual appraisal, including perceived fairness or group membership of others, may modulate empathic neuronal activations. Empathy often involves coactivations in further networks associated with social cognition, depending on the specific situation and information available in the environment. Empathy-related insular and cingulate activity may reflect domain-general computations representing and predicting feeling states in self and others, likely guiding adaptive homeostatic responses and goal-directed behavior in dynamic social contexts.</p>
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This article reviews the modern literature on two key aspects of the central circuitry of emotion - the prefrontal cortex (PFC) and the amygdala. There are several different functional divisions of the PFC including the dorsolateral, ventromedial and orbitofrontal sectors. Each of these regions plays some role in affective processing that shares the feature of representing affect in the absence of immediate rewards and punishments as well as in different aspects of emotional regulation. The amygdala appears to be crucial for the learning of new stimulus-threat contingencies and also appears to be important in the expression of cue-specific fear. Individual differences in both tonic activation and phasic reactivity in this circuit play an important role in governing affective style. Emphasis is placed upon affective chronometry, or the time course of emotional responding, as a key attribute of emotion that varies across individuals and is regulated by this circuitry.
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Objective: Mindfulness is a process whereby one is aware and receptive to present moment experiences. Although mindfulness-enhancing interventions reduce pathological mental and physical health symptoms across a wide variety of conditions and diseases, the mechanisms underlying these effects remain unknown. Converging evidence from the mindfulness and neuroscience literature suggests that labeling affect may be one mechanism for these effects.
Methods: Participants (n = 27) indicated trait levels of mindfulness and then completed an affect labeling task while undergoing functional magnetic resonance imaging. The labeling task consisted of matching facial expressions to appropriate affect words (affect labeling) or to gender-appropriate names (gender labeling control task).
Results: After controlling for multiple individual difference measures, dispositional mindfulness was associated with greater widespread prefrontal cortical activation, and reduced bilateral amygdala activity during affect labeling, compared with the gender labeling control task. Further, strong negative associations were found between areas of prefrontal cortex and right amygdala responses in participants high in mindfulness but not in participants low in mindfulness.
Conclusions: The present findings with a dispositional measure of mindfulness suggest one potential neurocognitive mechanism for understanding how mindfulness meditation interventions reduce negative affect and improve health outcomes, showing that mindfulness is associated with enhanced prefrontal cortical regulation of affect through labeling of negative affective stimuli.
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OBJECTIVE: The purpose of this study was to use functional magnetic resonance imaging (fMRI) to probe the neural circuitry associated with reactivity to negative and positive affective stimuli in patients with major depressive disorder before treatment and after 2 and 8 weeks of treatment with venlafaxine. Relations between baseline neural activation and response to treatment were also evaluated.
METHOD: Patients with major depressive disorder (N=12) and healthy comparison subjects (N=5) were scanned on three occasions, during which trials of alternating blocks of affective and neutral pictorial visual stimuli were presented. Symptoms were evaluated at each testing occasion, and both groups completed self-report measures of mood. Statistical parametric mapping was used to examine the fMRI data with a focus on the group-by-time interactions.
RESULTS: Patients showed a significant reduction in depressive symptoms with treatment. Group-by-time interactions in response to the negative versus neutral stimuli were found in the left insular cortex and the left anterior cingulate. At baseline, both groups showed bilateral activation in the visual cortices, lateral prefrontal cortex, and amygdala in response to the negative versus neutral stimuli, with patients showing greater activation in the visual cortex and less activation in the left lateral prefrontal cortex. Patients with greater relative anterior cingulate activation at baseline in response to the negative versus neutral stimuli showed the most robust treatment response.
CONCLUSIONS: The findings underscore the importance of the neural circuitry activated by negative affect in depression and indicate that components of this circuitry can be changed within 2 weeks of treatment with antidepressant medication.
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OBJECTIVE: Positron emission tomography was used to investigate the neural substrates of normal human emotional and their dependence on the types of emotional stimulus.
METHOD: Twelve healthy female subjects underwent 12 measurements of regional brain activity following the intravenous bolus administration of [15O]H2O as they alternated between emotion-generating and control film and recall tasks. Automated image analysis techniques were used to characterize and compare the increases in regional brain activity associated with the emotional response to complex visual (film) and cognitive (recall) stimuli.
RESULTS: Film- and recall-generated emotion were each associated with significantly increased activity in the vicinity of the medial prefrontal cortex and thalamus, suggesting that these regions participate in aspects of emotion that do not depend on the nature of the emotional stimulus. Film-generated emotion was associated with significantly greater increases in activity bilaterally in the occipitotemporparietal cortex, lateral cerebellum, hypothalamus, and a region that includes the anterior temporal cortex, amygdala, and hippocampal formation, suggesting that these regions participate in the emotional response to certain exteroceptive sensory stimuli. Recall-generated sadness was associated with significantly greater increases in activity in the vicinity of the anterior insular cortex, suggesting that this region participates in the emotional response to potentially distressing cognitive or interoceptive sensory stimuli.
CONCLUSIONS: While this study should be considered preliminary, it identified brain regions that participate in externally and internally generated human emotion.
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Selfhood and self-awareness, at least in humans, can be dissected into many levels. At one level, self-awareness describes a metacognitive aspect of consciousness wherein higher-order thought is directed through attentional focus on the self-object and self-related matters. This chapter explores the insights gained from neuroimaging studies into the brain substrates and mechanisms underlying such “high-level” self-referential processing. At another level, selfhood is reflected in self-recognition processes which discriminate self-related stimuli from other similar stimuli. Here, we examine the relevant neuroimaging evidence, focusing on self-face recognition as an exemplar. At a more fundamental level, we review what is known about the mental representation of the body, focusing on studies suggesting that a primary sense of self is ultimately derived from the neural representation of the body via interoception. These studies emphasize the continuous mapping of dynamic changes in internal state, whereby physiological demands and homeostatic imperatives dictate motivations and shape the contents of cognition. Here, converging neuroimaging evidence suggests that brain regions involved in representing internal physiological processes and making them available to conscious appraisal contribute to self-referential cognitions. This link is further apparent in the neural correlates of cognitive control and detachment techniques, such as mindfulness, that increasingly find clinical utility. Ultimately, inferences from neuroimaging regarding selfhood and self-awareness must cohere with evidence from lesion studies and with an increasingly sophisticated understanding of the brain as a connected network generating self-representations via a range of overlapping mechanisms.
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<p>Social neuro-science has recently started to investigate the neuronal mechanisms underlying our ability to understand the mental and emotional states of others. In this review, imaging research conducted on theory of mind (ToM or mentalizing) and empathy is selectively reviewed. It is proposed that even though these abilities are often used as synonyms in the literature these capacities represent different abilities that rely on different neuronal circuitry. ToM refers to our ability to understand mental states such as intentions, goals and beliefs, and relies on structures of the temporal lobe and the pre-frontal cortex. In contrast, empathy refers to our ability to share the feelings (emotions and sensations) of others and relies on sensorimotor cortices as well as limbic and para-limbic structures. It is further argued that the concept of empathy as used in lay terms refers to a multi-level construct extending from simple forms of emotion contagion to complex forms of cognitive perspective taking. Future research should investigate the relative contribution of empathizing and mentalizing abilities in the understanding of other people's states. Finally, it is suggested that the abilities to understand other people's thoughts and to share their affects display different ontogenetic trajectories reflecting the different developmental paths of their underlying neural structures. In particular, empathy develops much earlier than mentalizing abilities, because the former relys on limbic structures which develop early in ontogeny, whereas the latter rely on lateral temporal lobe and pre-frontal structures which are among the last to fully mature.</p>
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The nature of the affective deficit that characterizes social anhedonia is not well understood. Emotionally evocative visual stimuli were presented to undergraduates identified as anhedonic or normal, based on their scores on the revised Social Anhedonia Scale. The affective stimuli were chosen to elicit positive and negative emotion; a subset of slides were specifically chosen to include social-interpersonal content. In the acoustic startle paradigm, participants were administered startle probes (50-ms 95 dB white noise bursts) while viewing images from the International Affective Picture System. Socially anhedonic individuals did not differ from normally hedonic individuals in terms of their physiological response to the stimuli, regardless of the nature of the content of the stimuli. However, on the self-report measures of trait affectivity, the socially anhedonic individuals reported significantly lower levels of positive affect and higher levels of negative affect. These findings suggest that the affective deficits reported by socially anhedonic individuals are not global in nature.
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Positive affect elicited in a mother toward her newborn infant may be one of the most powerful and evolutionarily preserved forms of positive affect in the emotional landscape of human behavior. This study examined the neurobiology of this form of positive emotion and in so doing, sought to overcome the difficulty of eliciting robust positive affect in response to visual stimuli in the physiological laboratory. Six primiparous human mothers with no indications of postpartum depression brought their infants into the laboratory for a photo shoot. Approximately 6 weeks later, they viewed photographs of their infant, another infant, and adult faces during acquisition of functional magnetic resonance images (fMRI). Mothers exhibited bilateral activation of the orbitofrontal cortex (OFC) while viewing pictures of their own versus unfamiliar infants. While in the scanner, mothers rated their mood more positively for pictures of their own infants than for unfamiliar infants, adults, or at baseline. The orbitofrontal activation correlated positively with pleasant mood ratings. In contrast, areas of visual cortex that also discriminated between own and unfamiliar infants were unrelated to mood ratings. These data implicate the orbitofrontal cortex in a mother's affective responses to her infant, a form of positive emotion that has received scant attention in prior human neurobiological studies. Furthermore, individual variations in orbitofrontal activation to infant stimuli may reflect an important dimension of maternal attachment.
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Social relations between humans critically depend on our affective experiences of others. Oxytocin enhances prosocial behavior, but its effect on humans' affective experience of others is not known. We tested whether oxytocin influences affective ratings, and underlying brain activity, of faces that have been aversively conditioned. Using a standard conditioning procedure, we induced differential negative affective ratings in faces exposed to an aversive conditioning compared with nonconditioning manipulation. This differential negative evaluative effect was abolished by treatment with oxytocin, an effect associated with an attenuation of activity in anterior medial temporal and anterior cingulate cortices. In amygdala and fusiform gyrus, this modulation was stronger for faces with direct gaze, relative to averted gaze, consistent with a relative specificity for socially relevant cues. The data suggest that oxytocin modulates the expression of evaluative conditioning for socially relevant faces via influences on amygdala and fusiform gyrus, an effect that may explain its prosocial effects.
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This review provides an overview of the field of social neuroscience from a European perspective and focuses mainly on outlining research topics which originated in European laboratories. After a brief historical synopsis of the emergence of this young field, the most relevant findings related to the investigation of the neural networks underlying our capacity to understand the minds of others are summarized. More specifically, three routes of social cognition are distinguished: (1) our capacity to mentalize, or to infer intentions and beliefs of others, (2) our capacity to mimic and understand other's motor actions, and (3) our capacity to empathize, or to share and understand the feelings of others. More recent studies focusing on social emotions such as love, compassion, revenge or our sense of fairness will be discussed linking the field of social neuroscience to the even younger field of neuroeconomics, with the focus on the study of human social interactions using game theoretical paradigms. Finally, the use of a multi-method and multi-disciplinary research approach combining genetic, pharmacological, computational and developmental aspects is advocated and future directions for the study of interactive minds are discussed.
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Examined were electroencephalogram (EEG) asymmetries during the presence of discrete facial signs of emotion among 10-month-old infants who were tested in a standard stranger- and mother-approach paradigm that included a brief separation from mother. Data underscore the usefulness of EEG measures of hemispheric activation in differentiating among certain emotional states. (RH)
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