“…The relationship between wetting and EEG sleep state is not clear. Some studies report that wetting occurs more often during ‘stage 4’ or ‘slow wave sleep’ and rarely during REM sleep ( Pierce et al, 1961 , Ritvo et al, 1969 ) but others have failed to detect a relationship ( Mikkelsen et al, 1980 , Inoue et al, 1987 , Bader et al, 2002 ), while another study reported that wetting occurred primarily during periods of very deep sleep ( Wolfish et al, 1997 ). In line with the latter findings a more recent study using sophisticated EEG power analysis in adolescents and adults with primary nocturnal enuresis revealed an abnormally deep sleep in enuretics who, when water loaded prior to sleeping, failed to be roused and voided while continuing to sleep ( Hunsballe, 2000 ).…”