Fragmentation of slow wave sleep after onset of complete locked-in state.

[locked-in syndrome]

Locked-in syndrome (LIS ) as a result of brainstem lesions or progressive neurodegenerative disorders , such as amyotrophic lateral sclerosis (ALS ), is a severe medical condition in which a person is fully conscious but unable to move or talk . LIS can transition into complete locked-in syndrome (CLIS ) in which residual abilities to communicate through muscle twitches are entirely lost . It is unknown how CLIS affects circadian rhythm and sleep /wake patterns . Here we report a 39 -year -old ALS patient who transitioned from LIS to CLIS while brain activity was continuously recorded using electrocorticography (ECoG ) over one month . While we found no circadian rhythm in heart rate and body temperature , transition into CLIS was associated with increased fragmentation of slow wave sleep (SWS ) across the day . Total time in SWS did not change . SWS fragmentation might reflect progressive circadian system impairment and should be considered as a factor further limiting communication capabilities in these patients .