Owner-rated hyperactivity/impulsivity is associated with sleep efficiency in family dogs. A non-invasive EEG study

Subjective sleep disturbances are reported by humans with attention-deficit/hyperactivity disorder (ADHD). However, no consistent objective findings related to sleep disturbances led to sleep problems removal from ADHD diagnostic criteria. As a model for human ADHD with questionnaires validated for this purpose, dogs have been used also because their sleep physiology can be measured by non-invasive methods similarly to humans. We recorded spontaneous sleep EEG in family dogs during a laboratory session. We analyzed the association of sleep macrostructure and deep sleep (NREM) slow-wave activity (SWA) with a validated owner-rated ADHD questionnaire, assessing inattention (IA), hyperactivity/impulsivity (H/I) and total (T) scores. Higher H/I and T were associated with lower sleep efficiency and longer time awake after initial drowsiness and NREM. IA showed no associations with sleep variables. Further, no association was found between ADHD scores and SWA. Our results are in line with human studies in which poor sleep quality reported by ADHD subjects is associated with some objective EEG macrostructural parameters. This suggests that dogs’ H/I natural variation is useful to gain a deeper insight of ADHD neural mechanisms.