Open AccessCortical thinning and sleep slow wave activity reductions mediate age-related improvements in cognition during mid-late adolescence
Author(s) -
Ju Lynn Ong,
S Azrin Jamaluddin,
Jesisca Tandi,
Nicholas I Y N Chee,
Ruth L F Leong,
Reto Huber,
June C. Lo,
Michael W.L. Chee
Publication year - 2021
Publication title -
sleep
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.222
H-Index - 207
eISSN - 1550-9109
pISSN - 0161-8105
DOI - 10.1093/sleep/zsab206
Subject(s) - cognition , polysomnography , psychology , audiology , effects of sleep deprivation on cognitive performance , slow wave sleep , cognitive decline , developmental psychology , neuroscience , electroencephalography , medicine , dementia , disease
Study Objectives Gains in cognitive test performance that occur during adolescence are associated with brain maturation. Cortical thinning and reduced sleep slow wave activity (SWA) are markers of such developmental changes. Here we investigate whether they mediate age-related improvements in cognition. Methods 109 adolescents aged 15–19 years (49 males) underwent magnetic resonance imaging, polysomnography (PSG), and a battery of cognitive tasks within a 2-month time window. Cognitive tasks assessed nonverbal intelligence, sustained attention, speed of processing and working memory and executive function. To minimize the effect of sleep history on SWA and cognitive performance, PSG and test batteries were administered only after at least 8 nights of 9-h time-in-bed (TIB) sleep opportunity. Results Age-related improvements in speed of processing (r = 0.33, p = 0.001) and nonverbal intelligence (r = 0.24, p = 0.01) domains were observed. These cognitive changes were associated with reduced cortical thickness, particularly in bilateral temporoparietal regions (rs = −0.21 to −0.45, ps < 0.05), as well as SWA (r = −0.35, p < 0.001). Serial mediation models found that ROIs in the middle/superior temporal cortices, together with SWA mediated the age-related improvement observed on cognition. Conclusions During adolescence, age-related improvements in cognition are mediated by reductions in cortical thickness and sleep SWA.