Daily caffeine intake induces concentration-dependent medial temporal plasticity in humans: a multimodal double-blind randomized controlled trial

Cerebral Cortex, Volume 31, Issue 6, June 2021, Pages 3096-3106, https: //doi.org/10.1093/cercor/bhab005

Commentary

Caffeine is routinely used to combat high sleep pressure, but its regulatory interference with sleep and wakefulness can disrupt neural homeostasis, and sleep deprivation can lead to changes in human gray matter.

This double-blind, randomized, crossover study examined the effects of caffeine (3 x 150 mg/day) for 10 days on human gray matter volume (GMV) cerebral blood flow (CBF) by fMRI MP.

RAGE and arterial spin labeling sequences were analyzed in 20 habitual caffeine consumers compared to a 10-day placebo (3 x 150 mg/day).

Sleep pressure was quantified by electroencephalographic slow wave activity (SWA) during the previous night's sleep, and nonparametric voxel-based analysis revealed a significant reduction in medial temporal lobe (mTL) GMV.

Voxel-by-voxel CBF was adjusted to account for the reduction in perfusion after 10 days of caffeine intake compared to placebo.

Large GMV reductions were associated with increases in individual concentrations of caffeine and paraxanthine, but sleep SWA did not differ between conditions and was not associated with caffeine-induced GMV reductions.

Therefore, the data from this analysis do not suggest an association between sleep depth and changes in brain morphology during daily caffeine intake.

In conclusion, it is stated in this study that daily caffeine intake may induce neuroplasticity in mTL, depending on individual metabolic processes.