Control over experience? Magnitude of the attentional blink depends on meditative state

The information processing capacity of the human mind is limited, as is evidenced by the so-called ‘attentional-blink’ deficit. This deficit is believed to result from competition between stimuli for limited attentional resources. We examined to what extent advanced meditators can manipulate their attentional state and control performance on an attentional blink task. We compared the magnitude of the attentional blink between states of focused attention meditation (in which one focuses tightly on an object) and states of open monitoring meditation (in which one is simply aware of whatever comes into experience) in a sample of experienced meditators. We found a smaller attentional blink during open monitoring compared to focused attention meditation due to reduced T1 capture. Of note, this effect was only found for very experienced meditators (on average 10,704 h of experience). These data may suggest that very advanced practitioners can exert some control over their conscious experience.     

Long-term meditation: the relationship between cognitive processes,thinking styles and mindfulness

The aim of this study is to examine the relationship between meditation and cognitive functions. More in depth the purpose is to demonstrate that long-term meditation practice improves attention skills and cognitive flexibility. Eighteen long-term meditation practitioners were compared to a matched control group, who never practiced meditation. Each subject was tested, using computerized software (Presentation Software 9.90), which measured: attention, visual search abilities, working memory and Stroop’s interference tasks. Furthermore, we examined the relationship between long-term meditation practice, mindfulness skills and thinking styles, namely styles of processing information. The results showed significant differences between the two groups, demonstrating that long-term meditation is linked to improvements of attentional functions, working memory and cognitive flexibility.     

The protective role of long-term meditation on the decline of the executive component of attention in aging: a preliminary cross-sectional study

Life expectancy is constantly increasing. However, a longer life not always corresponds to a healthier life. Indeed, even normal aging is associated with a decline in different cognitive functions. It has been proposed that a central mechanism that could contribute to this widespread cognitive decline is an ineffective inhibitory attentional control. Meditation, to the other hand, has been associated, in young adults, to enhancement of several attentional processes. Nevertheless, attention is not a unitary construct. An influent model proposed the distinction of three subsystems: the alerting (the ability to reach and maintain a vigilance state), the orienting (the capacity of focusing attention on a subset of stimuli), and the conflict resolution or executive component (the ability to resolve conflict or allocate limited resources between competing stimuli). Here, we investigated, employing the Attentional Network Task (ANT), the specific impact of age on these three subcomponents, and the protective role of long-term meditation testing a group of older adults naïve to meditation, a group of age-matched adults with long-term practice of meditation, and a group of young adults with no previous meditation experience. We reported a specific decline of the efficiency of the executive component in elderly that was not observed in age-matched meditators. Our results are encouraging for the investigation of the potential beneficial impact of meditation on other cognitive processes that decline in aging such as memory. Moreover, they could inform geriatric healthcare prevention and intervention strategies, proposing a new approach for cognitive remediation in elderly populations.     

Exploring attentional disruption in fibromyalgia using the attentional blink

Disrupted attentional function in individuals with fibromyalgia syndrome (FMS) has been noted in a number of previous studies. The cognitive mechanisms related to this disruption are not well-understood. This study sought to identify whether differences exist in early attentional processing and attentional capacity in individuals with FMS measuring the attentional blink (AB). Early attentional function was assessed in 16 females with FMS and compared with 16 healthy age-matched females without FMS. Simple early visual stimulus target detection accuracy was not significantly different between groups. However, as target detection difficulty increased, individuals in the FMS group showed significantly poorer performance compared to healthy participants. Our findings suggest that attentional disruption in individuals with FMS is associated with deficits in the early allocation of attentional resources during the completion of tasks with higher attentional demand.     

Exploring attentional disruption in fibromyalgia using the attentional blink

Disrupted attentional function in individuals with fibromyalgia syndrome (FMS) has been noted in a number of previous studies. The cognitive mechanisms related to this disruption are not well-understood. This study sought to identify whether differences exist in early attentional processing and attentional capacity in individuals with FMS measuring the attentional blink (AB). Early attentional function was assessed in 16 females with FMS and compared with 16 healthy age-matched females without FMS. Simple early visual stimulus target detection accuracy was not significantly different between groups. However, as target detection difficulty increased, individuals in the FMS group showed significantly poorer performance compared to healthy participants. Our findings suggest that attentional disruption in individuals with FMS is associated with deficits in the early allocation of attentional resources during the completion of tasks with higher attentional demand.     

Mindfulness meditation improves cognition: Evidence of brief mental training

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.     

The effect of mindfulness meditation on time perception

Research has increasingly focussed on the benefits of meditation in everyday life and performance. Mindfulness in particular improves attention, working memory capacity, and reading comprehension. Given its emphasis on moment-to-moment awareness, we hypothesised that mindfulness meditation would alter time perception. Using a within-subjects design, participants carried out a temporal bisection task, where several probe durations are compared to “short” and “long” standards. Following this, participants either listened to an audiobook or a meditation that focussed on the movement of breath in the body. Finally, participants completed the temporal bisection task for a second time. The control group showed no change after the listening task. However, meditation led to a relative overestimation of durations. Within an internal clock framework, a change in attentional resources can produce longer perceived durations. This meditative effect has wider implications for the use of mindfulness as an everyday practice and a basis for clinical treatment.     

RSVP in orbit: Identification of single and dual targets in motion

Three experiments using rapid serial visual presentation (RSVP) tested participants' ability to detect targets in streams that are in motion. These experiments compared the ability to identify moving versus stationary RSVP targets and examined the attentional blink with pairs of targets that were moving or stationary. One condition presented RSVP streams in the center of the screen; a second condition used an RSVP that was orbiting in a circle, with participants instructed to follow the stream with their eyes; and a third condition had participants fixate in the middle while observing a circling RSVP stream. Relative to performance in stationary RSVP streams, participants were not markedly impaired in detecting single targets in RSVP streams that were moving, either with or without instructions to pursue the motion. In streams with two targets, a normal attentional blink effect was observed when participants were instructed to pursue the moving stream. When participants had to maintain central fixation as the RSVP stream moved, the attentional blink was nearly absent even when a trailing mask was added. We suggest that the reduction of the attentional blink for moving RSVP streams may reflect a reduced ability to perceive the temporal boundaries of the individual items.     

Mindfulness training modifies subsystems of attention

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.     

Meditation,mindfulness and cognitive flexibility

This study investigated the link between meditation, self-reported mindfulness and cognitive flexibility as well as other attentional functions. It compared a group of meditators experienced in mindfulness meditation with a meditation-naïve control group on measures of Stroop interference and the “d2-concentration and endurance test”. Overall the results suggest that attentional performance and cognitive flexibility are positively related to meditation practice and levels of mindfulness. Meditators performed significantly better than non-meditators on all measures of attention. Furthermore, self-reported mindfulness was higher in meditators than non-meditators and correlations with all attention measures were of moderate to high strength. This pattern of results suggests that mindfulness is intimately linked to improvements of attentional functions and cognitive flexibility. The relevance of these findings for mental balance and well-being are discussed.     

冥想对注意能力的影响

所有冥想方法都要对注意进行管理, 注意是冥想的核心机制。近期研究发现, 冥想显著提高了持续性注意、执行注意和选择性注意分配等多种注意能力。认知神经科学研究发现, 冥想使注意资源分配更有效; 长期冥想者表现出更高的失匹配负波波幅和更低的β波幅; 冥想增强了中央执行网络有关脑区的功能联结, 提高了突出网络有关脑区的活动; 注意聚焦冥想降低了默认网络有关脑区的活动。另外, 作为一种提高注意能力的方法, 冥想不仅适用于注意缺陷多动障碍患者和已康复的抑郁症患者等有注意相关障碍的临床群体, 也适用于儿童和老年人等多种年龄阶段的健康群体。未来应通过追踪研究探讨冥想的长期效果; 探索冥想中注意与情绪的交互作用; 根据群体特征设计出更有针对性的冥想。     

Occipital gamma activation during Vipassana meditation

Long-term Vipassana meditators sat in meditation vs. a control rest (mind-wandering) state for 21 min in a counterbalanced design with spontaneous EEG recorded. Meditation state dynamics were measured with spectral decomposition of the last 6 min of the eyes-closed silent meditation compared to control state. Meditation was associated with a decrease in frontal delta (1–4 Hz) power, especially pronounced in those participants not reporting drowsiness during meditation. Relative increase in frontal theta (4–8 Hz) power was observed during meditation, as well as significantly increased parieto-occipital gamma (35–45 Hz) power, but no other state effects were found for the theta (4–8 Hz), alpha (8–12 Hz), or beta (12–25 Hz) bands. Alpha power was sensitive to condition order, and more experienced meditators exhibited no tendency toward enhanced alpha during meditation relative to the control task. All participants tended to exhibit decreased alpha in association with reported drowsiness. Cross-experimental session occipital gamma power was the greatest in meditators with a daily practice of 10+ years, and the meditation-related gamma power increase was similarly the strongest in such advanced practitioners. The findings suggest that long-term Vipassana meditation contributes to increased occipital gamma power related to long-term meditational expertise and enhanced sensory awareness.     

Bilingualism and the increased attentional blink effect: evidence that the difference between bilinguals and monolinguals generalizes to different levels of second language proficiency

The attentional blink task involves rapid serial presentation of visual stimuli, two of which the participants have to report. The usual finding is that participants are impaired at reporting the second target if it appears in close temporal proximity to the first target. Previous research has shown that the effect is stronger in bilinguals than monolinguals. We investigated whether the difference between monolinguals and proficient bilinguals can be extended to bilinguals of different proficiency levels. Therefore, we replicated the paradigm in a large sample of Hindi–English bilinguals with different proficiency levels of English, as measured with a validated vocabulary test. We additionally measured the participants’ intelligence with the raven progressive matrices. We found that the size of the attentional blink effect correlates with the degree of second language proficiency and not with the degree of intelligence. This indicates that research on executive control functions can be done with bilinguals of different proficiency levels. Our results are also in line with recent findings showing that the attentional blink effect is not primarily due to limited processing resources.     

Greater efficiency in attentional processing related to mindfulness meditation

In this study, attentional processing in relation to mindfulness meditation was investigated. Since recent studies have suggested that mindfulness meditation may induce improvements in attentional processing, we have tested 20 expert mindfulness meditators in the attention network test. Their performance was compared to that of 20 age- and gender-matched controls. In addition to attentional network analyses, overall attentional processing was analysed by means of efficiency scores (i.e., accuracy controlled for reaction time). Better orienting and executive attention (reflected by smaller differences in either reaction time or error score, respectively) were observed in the mindfulness meditation group. Furthermore, extensive mindfulness meditation appeared to be related to a reduction of the fraction of errors for responses with the same reaction time. These results provide new insights into differences in attentional processing related to mindfulness meditation and suggest the possibility of increasing the efficiency in attentional processing by extensive mental training.     

Long-term concentrative meditation and cognitive performance among older adults

ABSTRACT

Background: The general consensus that cognitive abilities decline with advancing age is supported by several studies that have reported that older adults perform more poorly on multiple tests of cognitive performance as compared to younger adults. To date, preventive measures against this cognitive decline have been mainly focused on dietary, physical, and lifestyle behaviors which could allow older adults to maintain their cognitive abilities into late life. However, much less stress has been laid on evaluating meditation as a preventive measure in such cases in spite of the fact that the role of meditation on attention has been proved in several studies. In the current study, we extend this preliminary idea, examining the practice of concentrative meditation and the differences in the cognitive performance of older adults who have or have not employed this practice long term. Methodology: This was a cross-sectional study comparing the cognitive performance of meditators and non-meditators in the geriatric age group. Twenty (age > 55 years) long-term practitioners of Vihangam Yoga meditation (>10 years of practice) were recruited in the present study and were applied six paper–pencil neuropsychological tests for assessment of short-term memory, perceptual speed, attention, and executive functioning. The tests used were: (1) the Digit Span test, (2) the Stroop Color Word test, (3) the Trailmaking test, (4) the Letter Cancellation Task, (5) the digit symbol substitution test, and (6) the Rule Shift Card Test. All the tests were also applied to 20 age- and education-matched geriatric adults who have not practiced the meditation technique. Results: Vihangam Yogis showed significantly better performances in all these tests of attention (p < .05) except for the digit backward test, where a trend (p = .08) was found in favor of meditators. Conclusion: Long-term Vihangam Yoga meditators have superior cognitive abilities than non-meditators in the old age group. This technique should be studied further for its ability to prevent age-related cognitive decline.     

Age Differences in the Magnitude of the Attentional Blink

When people attend to a target in a rapid sequence of items, their perception of a subsequent target is impaired for about 500 ms. This is termed the attentional blink. In the present experiment, a dual task rapid serial presentation task (Raymond, Shapiro & Arnell, 1992) was used as a measure of inhibitory function of younger and older adults. We found that the attentional blink was larger among older adults as compared to younger adults, supporting Hasher and Zacks' (1988) inhibitory deficit hypothesis and current models of the attentional blink.     

Attentional orienting and executive control are affected by different types of meditation practice

Several studies have demonstrated the beneficial effects of meditation on attention. The present study investigated the relationship between focused attention (FA) and open monitoring (OM) meditation skills and the various functions of attention. In Experiment 1, we executed the attention network test and compared the performance of experts on dandao meditation with that of ordinary people on this test. The results indicated that the experts specializing in OM meditation demonstrated greater attentional orienting ability compared with those specializing in FA meditation and the control group. In addition, both expert groups registered improvements in their executive control abilities compared with the control group. In Experiment 2, we trained beginners in FA meditation for 3 months. The results showed that the experimental group exhibited significantly enhanced executive control ability. We infer that FA meditation skills promote executive control function and OM meditation skills promote both executive control and attentional orienting functions.     

Within-session practice eliminates age differences in cognitive control

ABSTRACT

Previous research employing short-term practice and long-term training have been successful in reducing cognitive control deficits in the elderly. The goal of this study was to examine the effect of practice within session on a demanding cognitive control task. Nineteen older adults and 16 young adults performed 720 trials of a cued version of the Stroop task, in which an instructional cue is presented before each individually presented Stroop stimulus. Statistical analyses focused on the most difficult color-naming condition in task-switching blocks. Overall, participants showed faster reaction times and decreased errors with practice, particularly on incongruent trials. Older adults showed a greater reduction in errors with practice than young adults. Moreover, older adults, but not young adults, showed a reduction in errors and reaction times with practice on incongruent trials. Findings further suggest that practice reduces age-related differences in cognitive control. Improvements in cognitive control functioning has implications for treating functional deficits in older adults.     

Attentional control in the aging brain: insights from an fMRI study of the stroop task

Several recent studies of aging and cognition have attributed decreases in the efficiency of working memory processes to possible declines in attentional control, the mechanism(s) by which the brain attempts to limit its processing to that of task-relevant information. Here we used fMRI measures of neural activity during performance of the color-word Stroop task to compare the neural substrates of attentional control in younger (ages: 21-27 years old) and older participants (ages: 60-75 years old) during conditions of both increased competition (incongruent and congruent neutral) and increased conflict (incongruent and congruent neutral). We found evidence of age-related decreases in the responsiveness of structures thought to support attentional control (e.g., dorsolateral prefrontal and parietal cortices), suggesting possible impairments in the implementation of attentional control in older participants. Consistent with this notion, older participants exhibited more extensive activation of ventral visual processing regions (i.e., temporal cortex) and anterior inferior prefrontal cortices, reflecting a decreased ability to inhibit the processing of task-irrelevant information. Also, the anterior cingulate cortex, a region involved in evaluatory processes at the level of response (e.g., detecting potential for error), showed age-related increases in its sensitivity to the presence of competing color information. These findings are discussed in terms of newly emerging models of attentional control in the human brain.     

Effects of long-term meditation practice on attentional biases towards emotional faces: An eye-tracking study

Attentional biases towards affective stimuli reflect an individual balance of appetitive and aversive motivational systems. Vigilance in relation to threatening information reflects emotional imbalance, associated with affective and somatic problems. It is known that meditation practice significantly improves control of attention, which is considered to be a tool for adaptive emotional regulation. In this regard, the main aim of the present study was to evaluate the influence of meditation on attentional bias towards neutral and emotional facial expressions. Eyes were tracked while 21 healthy controls and 23 experienced meditators (all males) viewed displays consisting of four facial expressions (neutral, angry, fearful and happy) for 10 s. Measures of biases in initial orienting and maintenance of attention were assessed. No effects were found for initial orienting biases. Meditators spent significantly less time viewing angry and fearful faces than control subjects. Furthermore, meditators selectively attended to happy faces whereas control subjects showed attentional biases towards both angry and happy faces. In sum we can conclude that long-term meditation practice adaptively affects attentional biases towards motivationally significant stimuli and that these biases reflect positive mood and predominance of appetitive motivation.