Expert Buddhist monks practicing Samatha (focused-attention) and Vipassana (open-monitoring) meditation showed increased neural signal complexity and widespread reductions in gamma-band long-range temporal correlations and 1/f slope compared to resting state. Analysis of deviation from criticality revealed distinct computational states between the two practices, suggesting their different phenomenological properties arise from specific dynamic characteristics. Contrary to most prior reports, oscillatory gamma power decreased during meditation, a difference attributed to correcting the power spectrum for broadband 1/f activity. These findings advance understanding of neural processes underlying focused-attention and open-monitoring meditation.
People who frequently recall their dreams show larger brain responses to sounds while awake and asleep and spend more time awake during the night, but their overall sleep structure is similar to that of low dream recallers. In a study of 18 high and 18 low dream recallers, sounds were played during a full night of sleep while brain activity was recorded. No differences in sleep microstructure—such as arousals, eye movements, or muscle twitches—were found between the groups. High recallers had more stimuli that caused awakenings and longer awakenings, but not more frequent or longer arousals.
People who often remember their dreams and those who rarely do show different brain activity patterns during sleep. Using deep convolutional networks on full-night EEG recordings from 36 subjects (18 high dream recall, 18 low dream recall), the authors trained separate classifiers for each sleep stage to predict which group a person belonged to. The classification accuracies revealed which sleep stages contain the best neural predictors of dream recall rate. A subject discriminator network was added as an adversary to ensure the model learned group-discriminating features rather than subject-specific ones. These features were visualized with a cue-combination Class Activation Map method. The findings are compared with prior studies, and future research directions are discussed.