Objective: To assess psychophysiological parameters in idiopathic rapid eye movements sleep behaviour disorder (RBD), in order to identify possible markers for pre or sub-clinical cognitive abnormalities.
Methods: Sixteen consecutive unmedicated patients with idiopathic RBD and 16 age- and sex-matched controls performed active and passive auditory oddball paradigms and an attentional test.
Results: There were no significant between-group latency and amplitude differences. The two groups showed a difference in the inter-peak interval between N100 and P200 in the active condition. A significant correlation between attentional matrices scores and N100 amplitude at Fz and Cz to standard stimuli in the passive condition was found in controls but not in patients.
Conclusions: In RBD there are minimal event-related potentials (ERPs) abnormalities involving the early stages of information processing.
Significance: ERPs are not sensitive to pre or sub-clinical cognitive abnormalities in RBD. In alternative, these findings might support the existence of a truly idiopathic RBD syndrome.