Buddhist meditation practices have been shown to create different states of consciousness.
A new study looked at how traditional Buddhist meditation affects how the brain processes sounds.
The results show that these meditations change brain activity in a way that tunes out sensory information.
Key Facts:
- 115 Tibetan Buddhist monks with at least 3 years of meditation experience participated.
- Brain activity was recorded while monks meditated and while in a relaxed state.
- Specific event-related potentials (ERPs) were measured that show brain response to sounds.
- During meditation, ERPs related to processing novelty, recognizing changes, and paying attention were reduced.
- The findings suggest meditation turns down sensory processing and disengages attention from external sights and sounds.
Source: International Journal of Pyshcophysiology (Vol. 181, Nov 2022)
Dalai Lama & Tibetan Buddhist monks
The study was conducted by researchers in Russia in collaboration with the Dalai Lama.
115 Tibetan Buddhist monks skilled in traditional meditation practices participated.
The monks’ brain activity was recorded using electroencephalography (EEG) while they were in two different states:
- Engaged in traditional Buddhist meditation practices
- Relaxed with eyes closed (control condition)
In both states, the monks passively listened to a sequence of sounds containing standards tones (beeps), deviant tones (animal noises), and novel noises (door slams).
Event-related potentials (ERPs) were measured, which are brain responses time-locked to hearing the sounds.
Specific ERPs can show how novel, rare, or changing sounds are processed.
The ERPs analyzed included:
- N1 and P2 – reflect early sound processing
- Mismatch negativity (MMN) – automatic detection of changes
- P3a – reaction to novelty
Comparing ERPs between meditation and relaxation states revealed how meditation impacts sound processing in the brain.
Meditation Reduces Brain’s Reactivity to Sounds
During meditation, several ERPs were reduced compared to relaxation:
- MMN was lower in amplitude and delayed in timing
- N1 and P2 to odd sounds were smaller
- P3a to novel sounds decreased
This suggests the meditative state decreases:
- Change detection
- Orienting response to novelty
- Early sensory processing
In other words, the brain becomes less reactive to and engaged with external sights and sounds.
This is consistent with the goal of tuning out sensory distractions during meditation.
MMN – Automatic Change Detection Dampened
The mismatch negativity (MMN) is a brain response that happens automatically when a rare “oddball” sound is detected among standard background sounds.
MMN does not require conscious attention – it reflects pre-attentive change detection. For example, hearing a dog bark amidst beeps.
During meditation, MMN was reduced in the monks. The amplitude (size) of MMN decreased and its timing was delayed.
This suggests detectability of changes in the sound environment is dampened down during meditative states.
N1 and P2 – Sensory Processing Suppressed
The N1 is a large negative ERP wave about 100 ms after a sound occurs.
It reflects early sensory processing.
P2 is a positive wave at about 200 ms related to processing physical sound features.
For deviant odd sounds, N1 and P2 amplitudes were smaller during meditation versus relaxation.
This points to a suppression of early sensory processing for external sounds while in a meditative state.
P3a – Novelty Orienting Response Diminished
The P3a is an ERP peaking around 300 ms in response to novel distracting events.
It reflects an involuntary orienting reaction.
Here, the P3a was elicited by unusual novel noises like door slams.
During meditation, P3a was decreased compared to relaxation, especially at frontal sites.
This suggests attention orienting to novelty and distracting events is reduced during meditative practice.
Implications of the Findings
Together, the ERP results indicate meditation dampens brain processes involved in monitoring the external sensory environment.
This manifests as:
- Reduced pre-attentive change detection
- Blunted sensory processing of sounds
- Diminished involuntary orienting to novelty
In other words, attention is withdrawn from external stimuli.
This is consistent with the introspective aims of meditation – to tune out distraction and turn attention inwards.
These findings agree with Buddhist descriptions of how meditation disengages one from sensory consciousness.
The results add neuroscience evidence about how traditional Buddhist practices alter sensory and cognitive processing in the brain.
Understanding How Meditation Changes the Brain
There is still much unknown about how different meditative states impact the brain.
But this study sheds light on how traditional Buddhist practices involving concentration and analytical introspection affect brain function.
Key aspects include:
Reduced Reactivity to Stimuli
A hallmark of the meditative state observed here is reduced reactivity to external events.
The brain becomes less responsive to changes, novelty, and sensory features in the environment.
Attention withdraws from external happenings.
This contrasts with being caught up in sensory stimuli during regular conscious wakefulness.
Altered Sense of Salience
Another effect is an altered sense of salience – what’s important and worth paying attention to.
Novel events lose their grabbing power over attention.
Deviant occurrences don’t stand out as much.
This reflects a shift in processing priorities inward rather than outward.
Transition to Detached Awareness
Withdrawing attention from the external world likely aids transition to a state of detached, equanimous awareness during meditation.
Letting go of stimuli reactions fosters a more serene, introspective space.
The observed ERP changes represent a neurocognitive “turning down” of sensory engagement.
Future meditation research questions
While this study provides new neuroscientific evidence about traditional Buddhist meditation, more research is needed.
Some questions still to be addressed:
- How do these practices specifically alter neural oscillations and connectivity?
- How do the findings translate to long-term traits in very advanced experts?
- How consistent are the effects across various meditative states and traditions?
- Can ERP markers distinguish levels of meditative expertise and intensity?
- What cognitive and clinical relevance do the alterations have?
In addition to event-related potentials, analyzing spectral power, functional connectivity, and neural complexity could reveal deeper mechanisms of how meditation changes brain function.
Meditation alters sensory & cognitive processing in the brain
This research takes important steps in unraveling how traditional Buddhist meditation practices change sensory and cognitive processing in the brain.
The discovered “turning down” of responsiveness to external stimuli provides neuroscience evidence that aligns with the introspective goals of these contemplative practices.
Understanding how meditation alters brain function gives clues into the neurocognitive underpinnings of altered states of consciousness.
The study demonstrates the value of pairing first-person experiential reports from contemplative traditions with third-person neuroscientific measurements.
This collaborative approach will continue elucidating the brain changes underlying different meditative states and their significance.
References
- Study: Traditional Buddhist meditations reduce mismatch negativity in experienced monk-practitioners
- Authors: S V Medvedev et al. (2022)
