Structural changes in brain morphology induced by brief periods of repetitive sensory stimulation

Abstract

), T1-weighted images were obtained using a 3T scanner pre-and post-stimulation. RSS was applied for 45 min to the dominant right hand, specifically to the fingertips of all fingers. At baseline, performance in the 2ptD task was associated with regional GM volume in the thalamus, primary somatosensory cortex, and primary visual cortex (negative association). After 45 min of rSS, we observed an improvement in 2ptD of the stimulated hand, whereas no improvement in tactile performance was seen on the non-stimulated side. These perceptual changes were accompanied by an increase in GM volume in the left somatosensory cortex and the degree of improvement correlated with GM volume changes in the insular cortex. Our results show that structural changes in the brain, specifically in regions receiving afferent input from the stimulated body site can be induced via a short-term intervention lasting only 45 min. However, the neurobiological correlates of these changes and the dynamics need to be further elucidated.