Role of Different Entropy Measures Derived in Canonical Frequency Bands in Studies on Meditation Practices
Journal Title: The 2nd Annual Meeting of International Center for Neuroscience Research - Year 2021, Vol 2, Issue 1
Abstract
Entropy is a non-linear measure used to quantify function and information processing between brain regions. It is a dimensionless quantity associated with the uncertainty applied here to analyze brain states and functions during meditation practice. It is hypothesized that low-entropy is associated with reduced content of conscious elements of functions and high-entropy with an elevation of attentiveness. The study aims at differentiating information extracted from each of the entropy measures considered in the proposed research and the utility of these measures in studying brain states and functions. Most studies on brain activity and processes using entropy measures have not considered analysis in different frequency bands. The study explores various entropy measures (approximate entropy (ApEn), sample entropy (SpEn), fuzzy entropy (FyEn), and minimum variance modified fuzzy entropy (MVMFEn)), and the role of these measures in different frequency bands to quantify the complexity in EEG before, after, and during meditation states. Fourteen long-term meditators with no prior history of neurological disorders, and a mean age of 42 ± 5 years with an experience of regular meditation practice of 23 ± 5 years, were chosen for the study after informed consent. The experimental protocol included two different rajayoga meditation types: peaceful soul consciousness (PM) and angelic (AM) states for 10 minutes each. Approximately five minutes of baseline recordings with eyes open condition were included before and after each meditation segment. EEG was recorded using 64 channel waveguard cap with an ANT neuro amplifier with a sampling rate of 1024 Hz. AM and PM's meditation segments are not randomized in the protocol as AM is a progressive state from PM state. Significantly increased entropy (p ≤ 0.05) during both meditative states compared to non-meditative states was observed across all the lobes in the delta and gamma frequency bands in the MVMFEn measure. A similar change in entropy pattern (p ≤ 0.05) is observed across all the entropy measures only in the frontal lobe in the delta band. In contrast, decreased entropy during meditative states is noted in theta bands of ApEn, SpEn, and FyEn measures but is not statistically significant. The proposed work is unique among studies comparing different entropy measures before, after, and during meditation. Significant changes observed in the frontal lobe in the delta band are related to the involvement of minimal consciousness of the brain. However, changes observed in the gamma band have been reported consistently in studies on long-term meditators, implying increased alertness. With the contradictory results of increased entropy both in delta and gamma frequency bands, it is necessary to analyze the temporal changes in entropy measures during the meditative state as meditative practices involve various functional states manifesting the different emotional, cognitive, and mystic experiences attained by expert meditators during the practice.
Authors and Affiliations
G. Pradeep Kumar*, Kanishka Sharma, A. Adarsh, A. G. Ramakrishnan
Keywords
Related Articles
- EP ID EP701734
- DOI -
- Views 110
- Downloads 0
TIMP-1, Secreted by a Distinct State of Reactive Astrocyte in Response to Aβ, Promotes Neuronal Survival and Improves Cognitive Functions in 5xFAD Mice
Astrocytes that respond to any pathological stimulus in brain including in Alzheimer’s disease (AD), by undergoing extensive remodeling at the molecular, functional and morphological levels, are termed as reactive astro...
The Role of Tamoxifen (A Selective Estrogen Receptor Modulator) on Neurological Score, Blood-Brain Barrier and Brain Edema after Traumatic Brain Injury in Male Rats: The Role of Matrix Metalloproteinase-9.
Introduction: Tamoxifen is an oral medication which is used for the treatment of breast cancer, and it acts on an estrogen receptor for agonist or antagonistic activity (effects) due to its effects on the environment. T...
Role of Different Entropy Measures Derived in Canonical Frequency Bands in Studies on Meditation Practices
Entropy is a non-linear measure used to quantify function and information processing between brain regions. It is a dimensionless quantity associated with the uncertainty applied here to analyze brain states and functio...
Modulation of the Mitochondrial ION Channel by Reactive Oxygen Species and Neurodegeneration
Mitochondria serves as a vital transit point for the transports of ions and metabolites across its transmembrane. On the other hand, these ions and metabolites conduct a significant role in the regulation of normal neu...
Roflumilast Attenuates Neuroinflammation and Cognitive Impairment in Intracerbroventricular-Streptozotocin Induced Rat Model of Sporadic Alzheimer’s Disease through Modulation of cAMP/BDNF Signaling Pathway
Sporadic Alzheimer’s disease (SAD) is the most complex and multifactorial neurodegenerative disease characterized by progressive cognitive deficits and memory loss. Phosphodiesterase (PDE) inhibitors prevent the breakd...