Caffeine increases brain complexity during sleep and shifts it toward a critical state

 A new study shows that even a moderate dose of caffeine alters brain activity during sleep, increasing complexity and nudging neural systems toward a high-efficiency processing state, especially in young adults during deep sleep.

Left column shows statistical differences (blue: reduced during caffeine, red: increased during caffeine), while SVM/LDA columns show classification accuracy between conditions (green). Dots indicate statistical significance (gray: p < 0.05, white: p < 0.01). Study: Caffeine induces age-dependent increases in brain complexity and criticality during sleep.

Caffeine ingestion leads to a reduction in long-range temporal correlations and also causes an increase in brain complexity, especially during non-rapid eye movement (NREM) sleep.

A recent study in Communications Biology assessed sleep electroencephalography (EEG) reports to understand the effects of caffeine on the brain, particularly during sleep.