Brainstem auditory-evoked potentials in two meditative mental states.
Sanjay Kumar, Hr Nagendra, Kv Naveen, Nk Manjunath, Shirley Telles
International Journal of Yoga July 1, 2010 DOI: 10.4103/0973-6131.72628 (opens in new tab) via PubMed
Summary
AI-generated from the abstractRepeating 'OM' mentally changes auditory-evoked potentials in the brainstem. Thirty experienced meditators (ages 20–55, average 29.1 years) were tested in four sessions: two control conditions (single-topic lecture and non-targeted thinking) and two meditation states (focusing on the symbol 'OM' and an effortless single-thought state of 'OM'). Wave V peak latency, indicating neural transmission at the inferior colliculus, increased significantly during non-targeted thinking, lecture, and focused meditation, but showed no change during the effortless single-thought state. This suggests that auditory information transmission is delayed in the first three conditions but not during the deeper meditative state.
Study at a glance
| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 30 |
| Population | Experienced meditators aged 20–55 years who had practiced meditating 'OM' for at least 6 months |
| Duration | Four sessions on four different days, each session consisting of pre, during, and post states |
| Keywords | Brainstem auditory-evoked potential Cancalata Dharana Dhyana Ekagrata |
| Key finding | Wave V peak latency increased during cancalata, ekagrata, and dharana but not during dhyana, indicating delayed auditory transmission at the inferior collicular level in the first three states. |
Abstract
Practicing mental repetition of "OM" has been shown to cause significant changes in the middle latency auditory-evoked potentials, which suggests that it facilitates the neural activity at the mesencephalic or diencephalic levels. The aim of the study was to study the brainstem auditory-evoked potentials (BAEP) in two meditation states based on consciousness, viz. dharana, and dhyana. Thirty subjects were selected, with ages ranging from 20 to 55 years (M=29.1; ±SD=6.5 years) who had a minimum of 6 months experience in meditating "OM". Each subject was assessed in four sessions, i.e. two meditation and two control sessions. The two control sessions were: (i) ekagrata, i.e. single-topic lecture on meditation and (ii) cancalata, i.e. non-targeted thinking. The two meditation sessions were: (i) dharana, i.e. focusing on the symbol "OM" and (ii) dhyana, i.e. effortless single-thought state "OM". All four sessions were recorded on four different days and consisted of three states, i.e. pre, during and post. The present results showed that the wave V peak latency significantly increased in cancalata, ekagrata and dharana, but no change occurred during the dhyana session. These results suggested that information transmission along the auditory pathway is delayed during cancalata, ekagrata and dharana, but there is no change during dhyana. It may be said that auditory information transmission was delayed at the inferior collicular level as the wave V corresponds to the tectum.