The mental self.
Hans C Lou, Markus Nowak, Troels W Kjaer
Progress in Brain Research 2005 DOI: 10.1016/s0079-6123(05)50014-1 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Neuroimaging study (positron emission tomography) with principal component analysis and transcranial magnetic stimulation experiments Peer reviewed |
|---|---|
| Interventions | Yoga nidra relaxation meditation Transcranial magnetic stimulation |
| Measures | Positron emission tomography, Principal component analysis, D2 receptor binding, Transcranial magnetic stimulation |
| Topics | Meditation |
| Keywords | Brain Humans Positron-emission tomography Yoga Ego Mental processes Consciousness Rest Relaxation therapy |
| Key findings | Yoga nidra meditation was accompanied by increased perfusion in sensory imagery regions and decreased perfusion in executive regions, with principal component analysis separating these into two networks explaining 25% and 18% of variance. The authors suggest dopaminergic regulation of this circuit based on increased striatal dopamine D2 receptor binding during meditation. Disrupting the precuneus with transcranial magnetic stimulation reduced self-judgment efficiency but not best-friend judgment, which the authors argue shows precuneus integrity is essential for self-reference but not reference to others. |
Abstract
In meditation both the quality and the contents of consciousness may be voluntarily changed, making it an obvious target in the quest for the neural correlate of consciousness. Here we present the results of a positron emission tomography study of yoga nidra relaxation meditation when compared with the normal resting conscious state. Meditation is accompanied by a relatively increased perfusion in the sensory imagery system: hippocampus and sensory and higher order association regions, with decreased perfusion in the executive system: dorsolateral prefrontal cortex, anterior cingulate gyrus, striatum, thalamus, pons, and cerebellum. To identify regions active in both systems we performed a principal component analysis of the results. This separated the blood flow data into two groups of regions, explaining 25 and 18% of their variance: One group corresponded to the executive system, and the other to the systems supporting sensory imagery. A small group of regions contributed considerably to both networks: medial parietal and medial prefrontal cortices, together with the striatum. The inclusion of the striatum and our subsequent finding of increased striatal dopamine binding to D2 receptors during meditation suggested dopaminergic regulation of this circuit. We then investigated the neural networks supporting episodic retrieval of judgments of individuals with different degrees of self-relevance, in the decreasing order: self, best friend, and the Danish queen. We found that all conditions activated a medial prefrontal - precuneus/posterior cingulate cortex, thalamus, and cerebellum. This activation occurred together with the activation of the left lateral prefrontal/temporal cortex. The latter was dependent on the requirement of retrieval of semantic information, being most pronounced in the "queen" condition. Transcranial magnetic stimulation, targeting precuneus, was then applied to the medial parietal region to transiently disrupt the normal function of the circuitry. We found a decreased efficiency of retrieval of self-judgment compared to the judgment of best friend. This shows that the integrity of the function of precuneus is essential for self-reference, but not for reference to others.
Comparable studies
Other experimental studies on meditation, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| The benefits of being present: Mindfulness and its role in psychological well-being. Cancer patients (clinical intervention study) | 2003 | Mixed methods: scale development, correlational, quasi-experimental, laboratory, experience-sampling, and clinical intervention study | |
| Loving-kindness meditation increases social connectedness. | 2008 | Controlled laboratory experiment | |
| Mindfulness and mind-wandering: Finding convergence through opposing constructs. | 2012 | Two studies: correlational study and experimental study | |
| Mental Training Enhances Attentional Stability: Neural and Behavioral Evidence | 2009 | Experimental study | |
| Mindfulness meditation and substance use in an incarcerated population. Incarcerated population | 2006 | Quasi-experimental with treatment-as-usual control condition |
Citations in the library
Cited by 17
- Self-awareness, self-regulation, and self-transcendence (S-ART): a framework for understanding the neurobiological mechanisms of mindfulness Frontiers in Human Neuroscience 2012
- Neural correlates of a mystical experience in Carmelite nuns Neuroscience Letters July 27, 2006
- Neural correlates of nondual awareness in meditation. Annals of the New York Academy of Sciences 2014
- Meditation-related activations are modulated by the practices needed to obtain it and by the expertise: an ALE meta-analysis study Frontiers in Human Neuroscience 2013
- Meditation effects within the hippocampal complex revealed by voxel-based morphometry and cytoarchitectonic probabilistic mapping Frontiers in Psychology 2013
and 12 more in the library
Cites 6
- A default mode of brain function Proceedings of the National Academy of Sciences January 16, 2001
- Physiological Effects of Transcendental Meditation Science March 27, 1970
- Functional connectivity in the resting brain: A network analysis of the default mode hypothesis Proceedings of the National Academy of Sciences December 27, 2002
- Stimulating illusory own-body perceptions. Nature September 1, 2002
- Increased dopamine tone during meditation-induced change of consciousness. Brain research. Cognitive brain research April 2002
and 1 more in the library