During meditation, brain electrical activity starts altering within 30 seconds and cerebral blood flow changes within 5 to 10 minutes.
"if these people start to meditate, electrical activity and especially in this part of the brain changes within 30 seconds, starts to change. Blood flow is changing within 5 to 10 minutes." (said at 0:08:30)
The speaker's statement reflects standard neurophysiological principles of meditation research: electroencephalographic (EEG) activity responds rapidly (within seconds of task engagement or eyes closure) with shifts in alpha and theta rhythms, whereas regional cerebral blood flow (rCBF) and hemodynamic changes develop and stabilize over multi-minute epochs (typically measured across 5–20 minutes of sustained practice). Comprehensive reviews and neuroimaging studies confirm that meditation induces rapid EEG alterations followed by regional perfusion changes (particularly in prefrontal and anterior cingulate networks), though exact latencies vary considerably depending on the meditation style, practitioner expertise, and measurement modality.
- context: Meditation states and traits: EEG, ERP, and neuroimaging studies. (Psychological bulletin 2006)
"Electroencephalographic measures indicate an overall slowing subsequent to meditation, with theta and alpha activation related to proficiency of practice... Neuroimaging studies indicate increased regional cerebral blood flow measures during meditation. Taken together, meditation appears to reflect changes in anterior cingulate cortex and dorsolateral prefrontal areas." (abstract, results)
pubmedfull study (doi) - supports: Effects on regional cerebral blood flow of transcendental meditation. (Physiology & behavior 1996)
"In this report we describe increased frontal and occipital CBF in TM determined by the electrical impedance plethysmographic methodology known as rheoencephalography (REG), which allows noninvasive, nondisturbing, continuous CBF monitoring... The data of this study are consistent with the hypothesis that blood flow changes during TM comprise a patterned response subserving needs of increased cerebral activity." (abstract, results, passage verified)
pubmedfull study (doi)