Research over the past two decades broadly supports the claim that mindfulness meditation - practiced widely for the reduction of stress and promotion of health - exerts beneficial effects on physical and mental health, and cognitive performance. Recent neuroimaging studies have begun to uncover the brain areas and networks that mediate these positive effects. However, the underlying neural mechanisms remain unclear, and it is apparent that more methodologically rigorous studies are required if we are to gain a full understanding of the neuronal and molecular bases of the changes in the brain that accompany mindfulness meditation.

The neuroscience of mindfulness meditation

Working memory (WM) is a cognitive system that strongly relates to a person’s ability to reason with novel information and direct attention to goal-relevant information. Due to the central role that WM plays in general cognition, it has become the focus of a rapidly growing training literature that seeks to affect broad cognitive change through prolonged training on WM tasks. Recent work has suggested that the effects of WM training extend to general fluid intelligence, attentional control, and reductions in symptoms of ADHD. We present a theoretically motivated perspective of WM and subsequently review the WM training literature in light of several concerns. These include (a) the tendency for researchers to define change to abilities using single tasks, (b) inconsistent use of valid WM tasks, (c) no-contact control groups, and (d) subjective measurement of change. The literature review highlights several findings that warrant further research but ultimately concludes that there is a need to directly demonstrate that WM capacity increases in response to training. Specifically, we argue that transfer of training to WM must be demonstrated using a wider variety of tasks, thus eliminating the possibility that results can be explained by task specific learning. Additionally, we express concern that many of the most promising results (e.g., increased intelligence) cannot be readily attributed to changes in WM capacity. Thus, a critical goal for future research is to uncover the mechanisms that lead to transfer of training.

https://analyseeconomique.files.wordpress.com/2012/10/is-working-memory-training-effective.pdf

Is working memory training effective

Does mindfulness training improve cognitive abilities? A systematic review of neuropsychological findings

“The Scaffolding Theory of Aging and Cognition (STAC)”, proposed in 2009, is a conceptual model of cognitive aging that integrated evidence from structural and functional neuroimaging to explain how the combined effects of adverse and compensatory neural processes produce varying levels of cognitive function. The model made clear and testable predictions about how different brain variables, both structural and functional, were related to cognitive function, focusing on the core construct of compensatory scaffolding. The present paper provides a revised model that integrates new evidence about the aging brain that has emerged since STAC was published 5 years ago. Unlike the original STAC model, STAC-r incorporates life-course factors that serve to enhance or deplete neural resources, thereby influencing the developmental course of brain structure and function, as well as cognition, over time. Life-course factors also influence compensatory processes that are engaged to meet cognitive challenge, and to ameliorate the adverse effects of structural and functional decline. The revised model is discussed in relation to recent lifespan and longitudinal data as well as emerging evidence about the effects of training interventions. STAC-r goes beyond the previous model by combining a life-span approach with a life-course approach to understand and predict cognitive status and rate of cognitive change over time.

/pdf/how-does-it-stac-up-revisiting-the-scaffolding-theory-of-4xp4mu9l57.pdf

How does it STAC up? Revisiting the scaffolding theory of aging and cognition.

The subjective experience of one's environment is constructed by interactions among sensory, cognitive, and affective processes. For centuries, meditation has been thought to influence such processes by enabling a nonevaluative representation of sensory events. To better understand how meditation influences the sensory experience, we used arterial spin labeling functional magnetic resonance imaging to assess the neural mechanisms by which mindfulness meditation influences pain in healthy human participants. After 4 d of mindfulness meditation training, meditating in the presence of noxious stimulation significantly reduced pain unpleasantness by 57% and pain intensity ratings by 40% when compared to rest. A two-factor repeated-measures ANOVA was used to identify interactions between meditation and pain-related brain activation. Meditation reduced pain-related activation of the contralateral primary somatosensory cortex. Multiple regression analysis was used to identify brain regions associated with individual differences in the magnitude of meditation-related pain reductions. Meditation-induced reductions in pain intensity ratings were associated with increased activity in the anterior cingulate cortex and anterior insula, areas involved in the cognitive regulation of nociceptive processing. Reductions in pain unpleasantness ratings were associated with orbitofrontal cortex activation, an area implicated in reframing the contextual evaluation of sensory events. Moreover, reductions in pain unpleasantness also were associated with thalamic deactivation, which may reflect a limbic gating mechanism involved in modifying interactions between afferent input and executive-order brain areas. Together, these data indicate that meditation engages multiple brain mechanisms that alter the construction of the subjectively available pain experience from afferent information.

https://www.jneurosci.org/content/jneuro/31/14/5540.full.pdf

Brain Mechanisms Supporting the Modulation of Pain by Mindfulness Meditation

http://jtoomim.org/brain-training/Zeidan2010_Mindfulness_Meditation.pdf

Mindfulness meditation improves cognition: Evidence of brief mental training☆

Participants in previous studies of brief mindfulness meditation (MM) are often tested immediately following a meditation session, making it difficult to separate several days of training from one-session effects. The current study examined the effects of a single session of 25 min of MM compared with a sham meditation (sham M) and a book-listening control. One session of both MM and sham M had a significant effect on state mindfulness compared with the control. Several mood subscales as well as total distress score on the Profile of Mood States (POMS) were also significantly different from control. However, neither meditation condition had significant effects on any of the attention and working memory tasks. These results indicate that one session of meditation was not sufficient to affect the cognitive tasks used in this study. Both MM and sham M positively affected mood states and heightened state mindfulness.

One-session mindfulness meditation: A randomized controlled study of effects on cognition and mood.

Mindfulness meditation (MM) training has been shown to have positive effects on working memory and focused attention tasks. Clarifying the construct of mindfulness is important so that mindfulness ...

Zhanna David

Papers

Mindfulness meditation improves cognition: Evidence of brief mental training☆

One-session mindfulness meditation: A randomized controlled study of effects on cognition and mood.

Trait Mindfulness and Cognitive Task Performance