Sleep habits, academic performance, and the adolescent brain structure

Abstract

Here we report the first and most robust evidence about how sleep habits are associated with regional brain grey matter volumes and school grade average in early adolescence. Shorter time in bed during weekdays, and later weekend sleeping hours correlate with smaller brain grey matter volumes in frontal, anterior cingulate, and precuneus cortex regions. Poor school grade average associates with later weekend bedtime and smaller grey matter volumes in medial brain regions. The medial prefrontal - anterior cingulate cortex appears most tightly related to the adolescents' variations in sleep habits, as its volume correlates inversely with both weekend bedtime and wake up time, and also with poor school performance. These findings suggest that sleep habits, notably during the weekends, have an alarming link with both the structure of the adolescent brain and school performance, and thus highlight the need for informed interventions.

Figure 1. Brain regions where grey matter volumes correlated with sleep habits.

Red colour and top right panel illustrate the DLPFC regions where GMV was correlated with time in bed on weekdays; light blue colour and bottom right panel illustrate the medial prefrontal and anterior cingulate regions where GMV correlated negatively with wake-up time on weekends; dark blue colour and bottom left panel illustrate the DLPFC, anterior cingulate and precuneus regions where GMV was negatively correlated with bedtime on weekends. All images are presented with height threshold p < 0.001, and FWE correction for multiple spatial comparisons across the whole brain (1200 voxels). The scatter plots are presented for the voxel of maximal statistical significance; the solid line represents the linear regression line. GMV is expressed in arbitrary units. BA = Brodmann area.