Sleep patterns in reading disabled children.

Sleep patterns in reading disabled (n = 24) and normal control (n = 15) 8-10-year-old boys were compared to examine suggested relationships among sleep, maturational and cognitive processes. Sleep was recorded in the laboratory for four consecutive nights (two adaptation, two baseline) using standard polysomnography. Analyses revealed variations across nights for both groups reflecting adaptation to the sleep laboratory, but such effects were attenuated in reading disabled subjects. Group comparisons on baseline sleep measures (nights 3 and 4 collapsed) revealed that reading disabled children showed significantly more stage 4 sleep, less rapid eye movement (REM) sleep, a longer REM onset latency and, related to this, an extended initial non-REM (NREM) cycle. Chronic sleep deprivation and maturational delay are prominent among factors that could result in such variations in sleep architecture, and these factors, alone or in combination, could impair information processing and contribute to cognitive deficits noted in reading disabled children.