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The scientific interest in meditation and mindfulness practice has recently seen an unprecedented surge. After an initial phase of presenting beneficial effects of mindfulness practice in various domains, research is now seeking to unravel the underlying psychological and neurophysiological mechanisms. Advances in understanding these processes are required for improving and fine-tuning mindfulness-based interventions that target specific conditions such as eating disorders or attention deficit hyperactivity disorders. This review presents a theoretical framework that emphasizes the central role of attentional control mechanisms in the development of mindfulness skills. It discusses the phenomenological level of experience during meditation, the different attentional functions that are involved, and relates these to the brain networks that subserve these functions. On the basis of currently available empirical evidence specific processes as to how attention exerts its positive influence are considered and it is concluded that meditation practice appears to positively impact attentional functions by improving resource allocation processes. As a result, attentional resources are allocated more fully during early processing phases which subsequently enhance further processing. Neural changes resulting from a pure form of mindfulness practice that is central to most mindfulness programs are considered from the perspective that they constitute a useful reference point for future research. Furthermore, possible interrelations between the improvement of attentional control and emotion regulation skills are discussed.

Recent theoretical and empirical work in cognitive science and neuroscience is brought into contact with the concept of the flow experience. After a brief exposition of brain function, the explicit-implicit distinction is applied to the effortless information processing that is so characteristic of the flow state. The explicit system is associated with the higher cognitive functions of the frontal lobe and medial temporal lobe structures and has evolved to increase cognitive flexibility. In contrast, the implicit system is associated with the skill-based knowledge supported primarily by the basal ganglia and has the advantage of being more efficient. From the analysis of this flexibility/efficiency trade-off emerges a thesis that identifies the flow state as a period during which a highly practiced skill that is represented in the implicit system's knowledge base is implemented without interference from the explicit system. It is proposed that a necessary prerequisite to the experience of flow is a state of transient hypofrontality that enables the temporary suppression of the analytical and meta-conscious capacities of the explicit system. Examining sensory-motor integration skills that seem to typify flow such as athletic performance, writing, and free-jazz improvisation, the new framework clarifies how this concept relates to creativity and opens new avenues of research.

In this article, the authors elaborate on 3 ideas advanced in P. Rozin and A. B. Cohen's (2003) innovative study of facial expression. Taking a cue from their discovery of new expressive behaviors (e.g., the narrowed eyebrows), the authors review recent studies showing that emotions are conveyed in more channels than usually studied, including posture, gaze patterns, voice, and touch. Building on their claim that confusion has a distinct display, the authors review evidence showing distinct displays for 3 self-conscious emotions (embarrassment, shame, and pride), 5 positive emotions (amusement, desire, happiness, love, interest), and sympathy and compassion. Finally, the authors offer a functional definition of emotion to integrate these findings on "new" displays and emotions.
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Concepts originating from ancient Eastern texts are now being explored scientifically, leading to new insights into mind/brain function. Meditative practice, often viewed as an emotion regulation strategy, has been associated with pain reduction, low pain sensitivity, chronic pain improvement, and thickness of pain-related cortices. Zen meditation is unlike previously studied emotion regulation techniques; more akin to ‘no appraisal’ than ‘reappraisal’. This implies the cognitive evaluation of pain may be involved in the pain-related effects observed in meditators. Using functional magnetic resonance imaging and a thermal pain paradigm we show that practitioners of Zen, compared to controls, reduce activity in executive, evaluative and emotion areas during pain (prefrontal cortex, amygdala, hippocampus). Meditators with the most experience showed the largest activation reductions. Simultaneously, meditators more robustly activated primary pain processing regions (anterior cingulate cortex, thalamus, insula). Importantly, the lower pain sensitivity in meditators was strongly predicted by reductions in functional connectivity between executive and pain-related cortices. Results suggest a functional decoupling of the cognitive-evaluative and sensory-discriminative dimensions of pain, possibly allowing practitioners to view painful stimuli more neutrally. The activation pattern is remarkably consistent with the mindset described in Zen and the notion of mindfulness. Our findings contrast and challenge current concepts of pain and emotion regulation and cognitive control; commonly thought to manifest through increased activation of frontal executive areas. We suggest it is possible to self-regulate in a more ‘passive’ manner, by reducing higher-order evaluative processes, as demonstrated here by the disengagement of anterior brain systems in meditators.

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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Several authors have argued that because mindfulness training involves repeated practice of the self-regulation of attention, it should lead to measurable improvements in attentional skills and related memory processes. Although a few studies have shown relationships between mindfulness training and performance-based tests of attention and memory, findings are mixed. In the present study, a sample of 33 adults with a long-term mindfulness meditation practice (average duration of 6 years) was compared with a demographically matched sample of nonmeditators on several widely used tests of attention and memory functioning, including sustained attention, attention switching, inhibition of elaborative processing, working memory, and short- and long-term memory. Group differences were nonsignificant for all of the attentional tasks. The only significant group differences were in short-term memory (both free and cued recall) and long-term memory (free recall only). Results suggest that the nature of the attentional and memory processing that is cultivated by mindfulness training requires clarification.

Tasks that tax working memory (WM) have consistently been found to decrease mind wandering. These findings may indicate that maintenance of mind wandering requires WM resources, such that mind wandering cannot persist when WM resources are being consumed by a task. An alternative explanation for these findings, however, is that mind wandering persists without the support of WM but is nonetheless decreased during any demanding task because good task performance requires that attention be restricted from task-unrelated thought (TUT). The present study tested these two competing theories by investigating whether individuals with greater WM resources mind-wander more during an undemanding task, as would be predicted only by the theory that WM supports TUT. We found that individuals with higher WM capacity reported more TUT in undemanding tasks, which suggests that WM enables the maintenance of mind wandering.
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Our outside world changes continuously, for example, when driving through traffic. An important question is how our brain deals with this constant barrage of rapidly changing sensory input and flexibly selects only newly goal-relevant information for further capacity-limited processing in working memory. The challenge our brain faces is experimentally captured by the attentional blink (AB): an impairment in detecting the second of two target stimuli presented in close temporal proximity among distracters. Many theories have been proposed to explain this deficit in processing goal-relevant information, with some attributing the AB to capacity limitations related to encoding of the first target and others assigning a critical role to on-line selection mechanisms that control access to working memory. The current study examined the role of striatal dopamine in the AB, given its known role in regulating the contents of working memory. Specifically, participants performed an AB task and their basal level of dopamine D2-like receptor binding was measured using PET and [F-18]fallypride. As predicted, individual differences analyses showed that greater D2-like receptor binding in the striatum was associated with a larger AB, implicating striatal dopamine and mechanisms that control access to working memory in the AB. Specifically, we propose that striatal dopamine may determine the AB by regulating the threshold for working memory updating, providing a testable physiological basis for this deficit in gating rapidly changing visual information. A challenge for current models of the AB lies in connecting more directly to these neurobiological data.
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Evidence that placebo acupuncture is an effective treatment for chronic pain presents a puzzle: how do placebo needles appearing to patients to penetrate the body, but instead sitting on the skin’s surface in the manner of a tactile stimulus, evoke a healing response? Previous accounts of ritual touch healing in which patients often described enhanced touch sensations (including warmth, tingling or flowing sensations) suggest an embodied healing mechanism. In this qualitative study, we asked a subset of patients in a singleblind randomized trial in irritable bowel syndrome to describe their treatment experiences while undergoing placebo treament. Analysis focused on patients’ unprompted descriptions of any enhanced touch sensations (e.g., warmth, tingling) and any significance patients assigned to the sensations. We found in 5/6 cases, patients associated sensations including “warmth” and “tingling” with treatment efficacy. The conclusion offers a “neurophenomenological” account of the placebo effect by considering dynamic effects of attentional filtering on early sensory cortices, possibly underlying the phenomenology of placebo acupuncture.
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<p>BACKGROUND: All therapists direct their attention in some manner during psychotherapy. A special form of directing attention, 'mindfulness', is recommended. This study aimed to examine whether, and to what extent, promoting mindfulness in psychotherapists in training (PiT) influences the treatment results of their patients. METHODS: The therapeutic course and treatment results of 124 inpatients, who were treated for 9 weeks by 18 PiTs, were compared. The PiTs were randomly assigned to 1 of 2 groups: (i) those practicing Zen meditation (MED; n = 9 or (ii) control group, which did not perform meditation (noMED; n = 9). The results of treatment (according to the intent-to-treat principle) were examined using the Session Questionnaire for General and Differential Individual Psychotherapy (STEP), the Questionnaire of Changes in Experience and Behavior (VEV) and the Symptom Checklist (SCL-90-R). RESULTS: Compared to the noMED group (n = 61), the patients of PiTs from the MED group (n = 63) had significantly higher evaluations (according to the intent-to-treat principle) for individual therapy on 2 STEP scales, clarification and problem-solving perspectives. Their evaluations were also significantly higher for the entire therapeutic result on the VEV. Furthermore, the MED group showed greater symptom reduction than the noMED group on the Global Severity Index and 8 SCL-90-R scales, including Somatization, Insecurity in Social Contact, Obsessiveness, Anxiety, Anger/Hostility, Phobic Anxiety, Paranoid Thinking and Psychoticism. CONCLUSIONS: This study indicates that promoting mindfulness in PiTs could positively influence the therapeutic course and treatment results in their patients.</p>
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Mindfulness-based cognitive therapy for children (MBCT-C) is a manualized group psychotherapy for children ages 9–13 years old, which was developed specifically to increase social-emotional resiliency through the enhancement of mindful attention. Program development is described along with results of the initial randomized controlled trial. We tested the hypotheses that children randomized to participate in MBCT-C would show greater reductions in (a) attention problems, (b) anxiety symptoms, and (c) behavior problems than wait-listed age and gender-matched controls. Participants were boys and girls aged 9–13 (N = 25), mostly from low-income, inner-city households. Twenty-one of 25 children were ethnic minorities. A randomized cross-lagged design provided a wait-listed control group, a second trial of MBCT-C, and a 3-month follow-up of children who completed the first trial. Measures included the Child Behavior Checklist, State-Trait Anxiety Inventory for Children, and Multidimensional Anxiety Scale for Children. Participants who completed the program showed fewer attention problems than wait-listed controls and those improvements were maintained at three months following the intervention [F (1, 1, 18) = 5.965, p = .025, Cohen’s d = .42]. A strong relationship was found between attention problems and behavior problems (r = .678, p < .01). Reductions in attention problems accounted for 46% of the variance of changes in behavior problems, although attention changes proved to be a non-significant mediator of behavior problems (p = .053). Significant reductions in anxiety symptoms and behavior problems were found for those children who reported clinically elevated levels of anxiety at pretest (n = 6). Results show that MBCT-C is a promising intervention for attention and behavior problems, and may reduce childhood anxiety symptoms.
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This experiment was designed to assess the differential impact of initially presenting affective information to the left versus right hemisphere on both the perception of and response to the input. Nineteen right-handed subjects were presented with faces expressing happiness and sadness. Each face was presented twice to each visual field for an 8-sec duration. The electro-oculogram (EOG) was monitored and fed back to subjects to train them to keep their eyes focused on the central fixation point as well as to eliminate trials confounded by eye movement artifact. Following each slide presentation, subjects rated the intensity of the emotional expression depicted in the face and their emotional reaction to the face on a series of 7-point rating scales. Subjects reported perceiving more happiness in response to stimuli initially presented to the left hemisphere (right visual field) compared to presentations of the identical faces to the right hemisphere (left visual field). This effect was predominantly a function of ratings on sad faces. A similar, albeit less robust, effect was found on self-ratings of happiness (the degree to which the face elicited the emotion in the viewer). These data challenge the view that the right hemisphere is uniquely involved in all emotional behavior. The implications of these findings for theories concerning the lateralization of emotional behavior are discussed.
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Working memory (WM) comprises operations whose coordinated action contributes to our ability to maintain focus on goal-relevant information in the presence of distraction. The present study investigated the nature of distraction upon the neural correlates of WM maintenance operations by presenting task-irrelevant distracters during the interval between the memoranda and probes of a delayed-response WM task. The study used a region of interest (ROIs) approach to investigate the role of anterior (e.g., lateral and medial prefrontal cortex--PFC) and posterior (e.g., parietal and fusiform cortices) brain regions that have been previously associated with WM operations. Behavioral results showed that distracters that were confusable with the memorandum impaired WM performance, compared to either the presence of non-confusable distracters or to the absence of distracters. These different levels of distraction led to differences in the regional patterns of delay interval activity measured with event-related functional magnetic resonance imaging (fMRI). In the anterior ROIs, dorsolateral PFC activation was associated with WM encoding and maintenance, and in maintaining a preparatory state, and ventrolateral PFC activation was associated with the inhibition of distraction. In the posterior ROIs, activation of the posterior parietal and fusiform cortices was associated with WM and perceptual processing, respectively. These findings provide novel evidence concerning the neural systems mediating the cognitive and behavioral responses during distraction, and places frontal cortex at the top of the hierarchy of the neural systems responsible for cognitive control.
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<p>As Titchener pointed out more than one hundred years ago, attention is at the center of the psychological enterprise. Attention research investigates how voluntary control and subjective experience arise from and regulate our behavior. In recent years, attention has been one of the fastest growing of all fields within cognitive psychology and cognitive neuroscience. This review examines attention as characterized by linking common neural networks with individual differences in their efficient utilization. The development of attentional networks is partly specified by genes, but is also open to specific experiences through the actions of caregivers and the culture. We believe that the connection between neural networks, genes, and socialization provides a common approach to all aspects of human cognition and emotion. Pursuit of this approach can provide a basis for psychology that unifies social, cultural, differential, experimental, and physiological areas, and allows normal development to serve as a baseline for understanding various forms of pathology. D.O. Hebb proposed this approach 50 years ago in his volume Organization of Behavior and continued with introductory textbooks that dealt with all of the topics of psychology in a common framework. Use of a common network approach to psychological science may allow a foundation for predicting and understanding human behavior in its varied forms.</p>

The current study investigated the effects of an 8-week mindfulness-based meditation training (MMT) intervention on attentional bias, engagement and disengagement of pain-related threat in fibromyalgia patients as compared to an age-matched control group. A well validated dot-probe task was used to explore early versus later stages of attentional processing through the use of two stimulus exposure durations (100, 500 ms) of pain-related threat words. The enduring effects of MMT were assessed 6-months after completion of MMT. Preliminary results suggest that MMT reduces avoidance of pain-related threat at early levels of processing, and facilitates disengagement from threat at later stages of processing. Furthermore, it appears that effects of MMT on early attentional threat processing do not remain stable after long-term follow-up.

Selective attention has been shown to bias sensory processing in favor of relevant stimuli and against irrelevant or distracting stimuli in perceptual tasks. Increasing evidence suggests that selective attention plays an important role during working memory maintenance, possibly by biasing sensory processing in favor of to-be-remembered items. In the current study, we investigated whether selective attention may also support working memory by biasing processing against irrelevant and potentially distracting information. Event-related potentials (ERPs) were recorded while subjects (n = 22) performed a delayed-recognition task for faces and shoes. The delay period was filled with face or shoe distractors. Behavioral performance was impaired when distractors were congruent with the working memory domain (e.g., face distractor during working memory for faces) relative to when distractors were incongruent with the working memory domain (e.g., face distractor during shoe working memory). If attentional biasing against distractor processing is indeed functionally relevant in supporting working memory maintenance, perceptual processing of distractors is predicted to be attenuated when distractors are more behaviorally intrusive relative to when they are nonintrusive. As such, we predicted that perceptual processing of distracting faces, as measured by the face-sensitive N170 ERP component, would be reduced in the context of congruent (face) working memory relative to incongruent (shoe) working memory. The N170 elicited by distracting faces demonstrated reduced amplitude during congruent versus incongruent working memory. These results suggest that perceptual processing of distracting faces may be attenuated due to attentional biasing against sensory processing of distractors that are most behaviorally intrusive during working memory maintenance.
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The scientific discovery of novel training paradigms has yielded better understanding of basic mechanisms underlying cortical plasticity, learning and development. This study is a first step in evaluating Tai Chi (TC), the Chinese slow-motion meditative exercise, as a training paradigm that, while not engaging in direct tactile stimulus training, elicits enhanced tactile acuity in long-term practitioners. The rationale for this study comes from the fact that, unlike previously studied direct-touch tactile training paradigms, TC practitioners focus specific mental attention on the body’s extremities including the fingertips and hands as they perform their slow routine. To determine whether TC is associated with enhanced tactile acuity, experienced adult TC practitioners were recruited and compared to age–gender matched controls. A blinded assessor used a validated method (Van Boven et al. in Neurology 54(12): 2230–2236, 2000) to compare TC practitioners’ and controls’ ability to discriminate between two different orientations (parallel and horizontal) across different grating widths at the fingertip. Study results showed that TC practitioners’ tactile spatial acuity was superior to that of the matched controls (P < 0.04). There was a trend showing TC may have an enhanced effect on older practitioners (P < 0.066), suggesting that TC may slow age related decline in this measure. To the best of our knowledge, this is the first study to evaluate a long-term attentional practice’s effects on a perceptual measure. Longitudinal studies are needed to examine whether TC initiates or is merely correlated with perceptual changes and whether it elicits long-term plasticity in primary sensory cortical maps. Further studies should also assess whether related somatosensory attentional practices (such as Yoga, mindfulness meditation and Qigong) achieve similar effects.
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We investigated the top-down influence of working memory (WM) maintenance on feedforward perceptual processing within occipito-temporal face processing structures. During event-related potential (ERP) recordings, subjects performed a delayed-recognition task requiring WM maintenance of faces or houses. The face-sensitive N170 component elicited by delay-spanning task-irrelevant grayscale noise probes was examined. If early feedforward perceptual activity is biased by maintenance requirements, the N170 ERP component elicited by probes should have a greater N170 amplitude response during face relative to house WM trials. Consistent with this prediction, N170 elicited by probes presented at the beginning, middle, and end of the delay interval was greater in amplitude during face relative to house WM. Thus, these results suggest that WM maintenance demands may modulate early feedforward perceptual processing for the entirety of the delay duration. We argue based on these results that temporally early biasing of domain-specific perceptual processing may be a critical mechanism by which WM maintenance is achieved.
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In recent years, three attentional networks have been defined in anatomical and functional terms. These functions involve alerting, orienting, and executive attention. Reaction time measures can be used to quantify the processing efficiency within each of these three networks. The Attention Network Test (ANT) is designed to evaluate alerting, orienting, and executive attention within a single 30-min testing session that can be easily performed by children, patients, and monkeys. A study with 40 normal adult subjects indicates that the ANT produces reliable single subject estimates of alerting, orienting, and executive function, and further suggests that the efficiencies of these three networks are uncorrelated. There are, however, some interactions in which alerting and orienting can modulate the degree of interference from flankers. This procedure may prove to be convenient and useful in evaluating attentional abnormalities associated with cases of brain injury, stroke, schizophrenia, and attention-deficit disorder. The ANT may also serve as an activation task for neuroimaging studies and as a phenotype for the study of the influence of genes on attentional networks.

The information processing capacity of the human mind is limited, as is evidenced by the attentional blink-a deficit in identifying the second of two targets (T1 and T2) presented in close succession. This deficit is thought to result from an overinvestment of limited resources in T1 processing. We previously reported that intensive mental training in a style of meditation aimed at reducing elaborate object processing, reduced brain resource allocation to T1, and improved T2 accuracy [Slagter, H. A., Lutz, A., Greischar, L. L., Francis, A. D., Nieuwenhuis, S., Davis, J., et al. Mental training affects distribution of limited brain resources. PloS Biology, 5, e138, 2007]. Here we report EEG spectral analyses to examine the possibility that this reduction in elaborate T1 processing rendered the system more available to process new target information, as indexed by T2-locked phase variability. Intensive mental training was associated with decreased cross-trial variability in the phase of oscillatory theta activity after successfully detected T2s, in particular, for those individuals who showed the greatest reduction in brain resource allocation to T1. These data implicate theta phase locking in conscious target perception, and suggest that after mental training the cognitive system is more rapidly available to process new target information. Mental training was not associated with changes in the amplitude of T2-induced responses or oscillatory activity before task onset. In combination, these findings illustrate the usefulness of systematic mental training in the study of the human mind by revealing the neural mechanisms that enable the brain to successfully represent target information.
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Spatial working memory is a cognitive brain mechanism that enables the temporary maintenance and manipulation of spatial information. Recent neuroimaging and behavioral studies have led to the proposal that directed spatial attention is the mechanism by which location information is maintained in spatial working memory. Yet it is unclear whether attentional involvement is required throughout the period of active maintenance or is only invoked during discrete task-phases such as mnemonic encoding. In the current study, we aimed to track the time-course of attentional involvement during spatial working memory by recording event-related brain potentials (ERPs) from healthy volunteers. In Experiment 1, subjects performed a delayed-recognition task. Each trial began with the presentation of a brief stimulus (S1) that indicated the relevant location that subjects were to maintain in working memory. A 4.8-5.3 sec delay interval followed during which a single task-irrelevant probe was presented. The delay interval concluded with a test item (S2) to which subjects made a response indicating whether the S2-location was the same as the S1-memory location. To determine if attention was differentially engaged during discrete phases of the trial, task-irrelevant probes were presented early (400-800 msec following S1-offset) or late (2600-3000 msec following S1-offset) during the delay interval. Sensory-evoked ERPs (P1 and N1) elicited by these irrelevant probes showed attention-like modulations with greater amplitude responses for probes occurring at the S1-memory locations in comparison to probes presented at other locations. This pattern was obtained for both early- and late-delay probes. Probe-evoked activity during delayed-recognition trials was similar to activity observed when spatial attention was explicitly focused on a location in visual space (Experiment 2). These results are consistent with a model of spatial working memory in which perceptual level selective attention is utilized throughout the entire period of active maintenance to keep relevant spatial information in mind.
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