Bibliography of Research works on History of Life Sciences 2

Frontiers in Psychology, 2015

Frontiers in Bioscience

Andrade et al. points out that about 30% of the inhabitants of a large metropolis suffer from mental disorders (10). Several meta-analysis have also shown that meditation can be used for treatment different psychological disorders with positive outcomes (11), (12). In this scenario, the use of adequate scientific methodology and instruments to observe the phenomena associated with meditation becomes important and allows health professionals to encourage meditation practice (13). Although there may be some differences between meditation practices such as focused attention (FA) and open monitoring (OM) and their correlates dharana (concentration) and dhyana (meditation) in the ancient texts (14), such techniques share many similarities. Here, we will review, the effects of meditation on brain structure and function, raise some methodological questions and will not discuss semantic differences. For example, in cross-sectional studies, conclusions about the results of meditation might be mistaken for pre-existing individual differences. Moreover, if we take the effects of meditation into account, we should also consider state and trait (15), where state encompasses the alterations caused during some practice, while trait encompasses those that transform baseline patterns and remain even when the individual is not meditating. In the present scenario, researches are more focused on the psychobiological effects of meditation as a cognitive training than on the reports of the mystical states of trance described as nirvana or samadhi, which were precursors for the first meditation studies (16), (17). The aim of this study was to review structural and functional magnetic resonance imaging studies about meditation.

2024

Cognitive Processing, 2009

Meditation is an ancient spiritual practice, which aims to still the fluctuations of the mind. We investigated meditation with fMRI in order to identify and characterise both the "neural switch" mechanism used in the voluntary shift from normal consciousness to meditation and the "threshold regulation mechanism" sustaining the meditative state. Thirty-one individuals with 1.5-25 years experience in meditation were scanned using a blocked on-off design with 45 s alternating epochs during the onset of respectively meditation and normal relaxation. Additionally, 21 subjects were scanned during 14.5 min of sustained meditation. The data were analysed with SPM and ICA. During the onset of meditation, activations were found bilaterally in the putamen and the supplementary motor cortex, while deactivations were found predominately in the right hemisphere, the precuneus, the posterior cingulum and the parieto-temporal area. During sustained meditation, SPM analysis revealed activation in the head of nucleus caudatus. Extensive deactivations were observed in white matter in the right hemisphere, i.e. mainly in the posterior occipito-parieto-temporal area and in the frontal lobes. ICA identified 38 components including known baseline-resting state components, one of which not only overlaps with the activated area revealed in the SPM analysis but extends further into frontal, temporal, parietal and limbic areas, and might presumably constitute a combination of frontoparietal and cinguloopercular task control systems. The identified component processes display varying degrees of correlation. We hypothesise that a proper characterisation of brain processes during meditation will require an operational definition of brain dynamics matching a stable state of mind. An investigation of brain processes supporting meditation 1 The citations from Patanjali have been adapted from the referenced translations by the first author.

Meditation is a family of mental practices that encompasses a wide array of techniques employing distinctive mental strategies. We systematically reviewed 78 functional neuroimaging (fMRI and PET) studies of meditation, and used activation likelihood estimation to meta-analyze 257 peak foci from 31 experiments involving 527 participants. We found reliably dissociable patterns of brain activation and deactivation for four common styles of meditation (focused attention, mantra recitation, open monitoring , and compassion/loving-kindness), and suggestive differences for three others (visualization, sense-withdrawal, and non-dual awareness practices). Overall, dissociable activation patterns are congruent with the psychological and behavioral aims of each practice. Some brain areas are recruited consistently across multiple techniques—including insula, pre/supplementary motor cortices, dorsal anterior cingulate cortex, and frontopolar cortex—but convergence is the exception rather than the rule. A preliminary effect-size meta-analysis found medium effects for both activations (d = 0.59) and deactivations (d = −0.74), suggesting potential practical significance. Our meta-analysis supports the neu-rophysiological dissociability of meditation practices, but also raises many methodological concerns and suggests avenues for future research.

Since 1995, he has been a research fellow at the Department of Neuroradiology, University of Tübingen, performing fMRI studies on a variety of research topics. He is involved in building MR compatible stimulation devices and programming MR pulse sequences and analysis software.

Brain and cognition, 2014

The most diffuse forms of meditation derive from Hinduism and Buddhism spiritual traditions. Different cognitive processes are set in place to reach these meditation states. According to an historical-philological hypothesis (Wynne, 2009) the two forms of meditation could be disentangled. While mindfulness is the focus of Buddhist meditation reached by focusing sustained attention on the body, on breathing and on the content of the thoughts, reaching an ineffable state of nothigness accompanied by a loss of sense of self and duality (Samadhi) is the main focus of Hinduism-inspired meditation. It is possible that these different practices activate separate brain networks. We tested this hypothesis by conducting an activation likelihood estimation (ALE) meta-analysis of functional magnetic resonance imaging (fMRI) studies. The network related to Buddhism-inspired meditation (16 experiments, 263 subjects, and 96 activation foci) included activations in some frontal lobe structures asso...

Perceptual and Motor Skills, 2010

Social cognitive and affective neuroscience, 2013

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 (ALE) meta-analysis found eight brain regions consistently altered in meditators, including areas key to meta-awareness (frontopolar cortex/BA 10), 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). Effect size meta-analysis (calculating 132 effect sizes from 16 studies) suggests a global 'medium' effect size (Cohen'sd = 0.46;r = .19). Publication bias and methodological limitations are strong concerns, however. Further research using rigorous methods is required to definitively link meditation practice to altered brain morphology.