INTRODUCTION AND OBJECTIVES: Parents of enuretic children with daytime-symptoms often report their child losing bladder-control and wetting himself while playing. It is known that children suffering from enuresis are characterized by a reduced PPI compared to healthy children (Ornitz et al.).

The hypothesis is suggestive that intensive playing leads to a strong decrease of PPI and consecutive wetting. Two questions are important: Does the PPI change while concentrating and is this difference more explicit in children with daytime-enuresis?

METHODS: 44 healthy children (26 girls and 18 boys), aged from 5 - 10 (median 8) and31 children suffering from enuresis (5 - 14 years) were examined. 14 of the latter had non-mono-symptomatic Enuresis (nmE), 17 were mono-symptomatic (mE). PPI was determined during two cycles: while watching an animated film (relaxed state) and while playing “Mario Kart” on Nintendo’s Wii ® (concentrated state). During each cycle the startle-reflex and its inhibition by a 60ms earlier applied sound (PPI) were measured. The cycle order was randomized.

RESULTS: A significant decrease of the PPI during concentration was shown: In relaxed state the PPI of the controls was 53%, when concentrating it was 21.5% (p=0.00038). While the decrease of PPI in mE was only mild (from 71% to 68%) the loss of central reflex-control was complete in nmE (40% to 0%, p=0,009).

CONCLUSIONS: First of all these findings confirm the genesis of enuresis by an impaired “sensorimotor-gating”, and second they provide a convincing neurophysiologic correlate for wetting while playing.

Source of Funding: none