Effect on brain structure (review & meta-analysis)

Fox, K. C., et al. (2014). Is meditation associated with altered brain structure? A systematic review and meta-analysis of morphometric neuroimaging in meditation practitioners. Neuroscience & Biobehavioral Reviews, 43, 48-73. Full text.

From the Abstract: Numerous studies have begun to address how the brain’s gray and white matter may be shaped by meditation. This research is yet to be integrated, however, and two fundamental questions remain: Is meditation associated with altered brain structure? If so, what is the magnitude of these differences? To address these questions, we reviewed and meta-analyzed 123 brain morphology differences from 21 neuroimaging studies examining ∼300 meditation practitioners.

Anatomical likelihood estimation meta-analysis found eight brain regions consistently altered in meditators, including areas key to meta-awareness, exteroceptive and interoceptive body awareness (sensory cortices and insula), memory consolidation and reconsolidation (hippocampus), self and emotion regulation (anterior and mid cingulate; orbitofrontal cortex), and intra- and interhemispheric communication (superior longitudinal fasciculus; corpus callosum).

Neurobiological effects of meditation and mindfulness

Esch, T. (2014). The Neurobiology of Meditation and Mindfulness. In Meditation–Neuroscientific Approaches and Philosophical Implications (pp. 153-173). Springer International Publishing. Summary of book chapter

Neurobiological effects of meditation and mindfulness can be detected in the brain as functional and also structural alterations in grey and white matter, particularly in areas related to attention and memory, interoception and sensory processing, or self- and auto-regulation (including control of stress and emotions). On the molecular level, dopamine and melatonin are found to increase, serotonin activity is modulated, and cortisol as well as norepinephrine have been proven to decrease.

These findings are reflected in functional and structural changes documented by imaging techniques such as fMRI or EEG. They may be relevant for medicine and health care, especially with reference to therapeutic strategies for behavior change and life-style modification, or in association with stress regulation and the treatment of addiction. Neuronal mechanisms of mindfulness can be divided into four areas: attention regulation, body awareness, emotion regulation and self-perception.

See also: How meditation can reshape our brain. TED talk by neuroscientist Sara Lazar. Her brain scans show meditation can actually change the size of key regions of our brain, improving our memory and making us more empathetic, compassionate, and resilient under stress.