Repetitive speech elicits widespread deactivation in the human cortex: the "Mantra" effect?
Aviva Berkovich-Ohana, Meytal Wilf, Roni Kahana, Amos Arieli, Rafael Malach
Brain and Behavior July 1, 2015 DOI: 10.1002/brb3.346 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 23 |
| Population | Nonmeditators |
| Topics | Default mode network Meditation |
| Keywords | FMRI Global inhibition Mantra |
| Key findings | Silent repetitive speech induced widespread reduction in BOLD signal, centered on the default mode network, without significant positive BOLD activity elsewhere. |
Abstract
Mantra (prolonged repetitive verbal utterance) is one of the most universal mental practices in human culture. However, the underlying neuronal mechanisms that may explain its powerful emotional and cognitive impact are unknown. In order to try to isolate the effect of silent repetitive speech, which is used in most commonly practiced Mantra meditative practices, on brain activity, we studied the neuronal correlates of simple repetitive speech in nonmeditators - that is, silent repetitive speech devoid of the wider context and spiritual orientations of commonly practiced meditation practices. We compared, using blood oxygenated level-dependent (BOLD) functional magnetic resonance imaging (fMRI), a simple task of covertly repeating a single word to resting state activity, in 23 subjects, none of which practiced meditation before. We demonstrate that the repetitive speech was sufficient to induce a widespread reduction in BOLD signal compared to resting baseline. The reduction was centered mainly on the default mode network, associated with intrinsic, self-related processes. Importantly, contrary to most cognitive tasks, where cortical-reduced activation in one set of networks is typically complemented by positive BOLD activity of similar magnitude in other cortical networks, the repetitive speech practice resulted in unidirectional negative activity without significant concomitant positive BOLD. A subsequent behavioral study showed a significant reduction in intrinsic thought processes during the repetitive speech condition compared to rest. Our results are compatible with a global gating model that can exert a widespread induction of negative BOLD in the absence of a corresponding positive activation. The triggering of a global inhibition by the minimally demanding repetitive speech may account for the long-established psychological calming effect associated with commonly practiced Mantra-related meditative practices.
Comparable studies
Other observational and cohort studies on default mode network, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| A default mode of brain function Normal adult human brain | 2001 | Observational study | |
| Resting-State Functional Connectivity Reflects Structural Connectivity in the Default Mode Network Healthy subjects | 2008 | Observational cohort | |
| Meditation experience is associated with increased cortical thickness Participants with extensive Insight meditation experience and matched controls | 2005 | Observational cohort | n = 20 |
| Meditation experience is associated with differences in default mode network activity and connectivity Experienced meditators and matched meditation-naive controls | 2011 | Observational cohort | |
| The precuneus/posterior cingulate cortex plays a pivotal role in the default mode network: Evidence from a partial correlation network analysis Healthy subjects | 2008 | Observational study |
Citations in the library
Cited by 17
- Psychedelics, Meditation, and Self-Consciousness Frontiers in Psychology September 4, 2018
- Brain Network Reconfiguration and Perceptual Decoupling During an Absorptive State of Consciousness. Cerebral Cortex July 1, 2016
- Beyond the veil of duality—topographic reorganization model of meditation Neuroscience of Consciousness 2022
- Implicit-explicit gradient of nondual awareness or consciousness as such. Neuroscience of Consciousness October 8, 2021
- Editorial: What can Neuroscience Learn from Contemplative Practices? Frontiers in Psychology November 10, 2015
and 12 more in the library
Cites 20
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- Effects of model-based physiological noise correction on default mode network anti-correlations and correlations Neuroimage May 15, 2009
- Functional brain mapping of the relaxation response and meditation Neuroreport May 1, 2000
- Cooperation between the default mode network and the frontal–parietal network in the production of an internal train of thought Brain Research April 15, 2011
and 15 more in the library