Deficits in learning and overnight memory consolidation in children with mild sleep-disordered breathing

Sleep disordered breathing (SDB) has its peak incidence in early childhood, but research into the impact of disrupted sleep on learning and overnight memory consolidation has been largely neglected in this population. Hence, we aimed to determine if children with SDB show deficits in learning and overnight consolidation of declarative and procedural memories compared to healthy control (HC) children. Forty-nine children aged 7-16 years (24 SDB, 25 HC) completed a cognitive battery, including two declarative (one verbal, one visual) and one procedural memory task. We manipulated the level of learning (three learning trials or 60% set criterion) on the visual memory task. Recall was assessed at two delays (30 minutes and overnight). Children with SDB underwent an overnight polysomnography sleep study. On declarative visual memory tasks, children with SDB needed more learning trials to reach the set criterion but had intact overnight consolidation. Within the SDB group, more trials to reach the criterion was associated with less time in NREM2 sleep. On the procedural memory task, the opposite pattern of intact learning but reduced overnight consolidation was found. Within the SDB group, worse overnight procedural memory consolidation was associated with less NREM2 sleep and more NREM3 sleep. School-aged children with SDB had deficits in overnight procedural memory consolidation and reduced declarative learning. These findings highlight the adverse consequences of SDB on memory and learning in children and underscore the need to assess recovery of cognitive deficits with treatment in future studies.