Sleep-related modifications of EEG connectivity in the sensory-motor networks in Huntington Disease: An eLORETA study and review of the literature

Objective: To evaluate EEG functional connectivity in the sensory-motor network, during wake and sleep, in patients with Huntington Disease (HD). Methods: 23 patients with HD and 23 age- and sex-matched healthy controls were enrolled. EEG connectivity analysis was performed by means of exact Low Resolution Electric Tomography (eLORETA). Results: In wake, HD patients showed an increase of delta lagged phase synchronization (T = 3.60; p <. 0.05) among Broadman's Areas (BA) 6-8 bilaterally; right BA 6-8 and right BA 1-2-3; left BA 1-2-3 and left BA 4. In NREM, HD patients showed an increase of delta lagged phase synchronization (T = 3.56; p <. 0.05) among left BA 1-2-3 and right BA 6-8. In REM, HD patients showed an increase of lagged phase synchronization (T = 3.60; p <. 0.05) among the BA 6-8 bilaterally (delta band); left BA 1-2-3 and right BA 1-2-3 (theta); left BA 1-2-3 and right BA 4 (theta); left BA 1-2-3 and right BA 1-2-3 (alpha). Conclusions: Our results may reflect an abnormal function of the motor areas or an effort to counterbalance the pathological motor output. Significance: Our results may help to understand the pathophysiology of sleep-related movement disorders in Huntington's Disease, and to define therapeutically strategies.