Enhanced stimulus-induced and stimulus-free gamma in open-eye meditators
Ankan Biswas, Srishty Aggarwal, Kanishka Sharma, Supratim Ray
bioRxiv February 22, 2024 preprint DOI: 10.1101/2024.02.19.581028 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational study comparing meditators and controls |
|---|---|
| Population | Meditators and controls |
| Measures | EEG, power spectral density (PSD) slope |
| Key findings | Stimulus-induced gamma and stimulus-free gamma were both stronger in meditators than controls. During meditation, the two gamma signatures coexisted but were unrelated and prominent in occipital and fronto-temporal regions, respectively. Meditators also had steeper power spectral density slopes, which the authors suggest may reflect enhanced inhibitory mechanisms and potential protection against aging and neurodegeneration. |
Abstract
Visual stimuli induce “narrowband” gamma oscillations (30-70 Hz) that are linked to attention/binding and attenuate with aging and neurodegeneration. In contrast, meditation increases power in a broad frequency range (>25 Hz). However, the effect of meditation on stimulus-induced gamma is unknown. We recorded EEG from meditators and controls performing open-eye meditation while gamma-inducing stimuli were presented before, during and after meditation. We found that stimulus-induced gamma, like stimulus-free gamma, was stronger in meditators. Interestingly, both gamma signatures co-existed during meditation but were unrelated and prominent in occipital and fronto-temporal regions, respectively. Further, power spectral density (PSD) slope, which becomes shallower with aging, was steeper for meditators. Meditation could boost inhibitory mechanisms leading to stronger gamma and steeper PSDs, potentially providing protection against aging and neurodegeneration. One line summary: Stimulus-induced and stimulus-free gamma are stronger in open-eye meditators.