Mirroring of a simple motor behavior in disorders of consciousness.
OBJECTIVE
In patients suffering from Disorders of Consciousness (DOC) electrophysiological recordings at bedside could serve as a complimentary and economical tool to improve diagnosis. We utilized a motor observation and imagination paradigm to gain new insights on preserved cognitive processing in DOC.


METHODS
EEG brain oscillations were analyzed in 10 VS/UWS (Vegetative State/Unresponsive Wakefulness Syndrome) patients and 7 MCS (Minimally Conscious State) patients and 21 controls during observation and imagination of a grasping movement and group statistics were conducted.


RESULTS
While control subjects showed a typical desynchronization at 8-15Hz during observation of a movement, MCS patients presented an analogue response at 8-10Hz, but exhibited a synchronization at 12-15Hz. The VS group did not show a systematic response. Imagery-related activation was only sustained for 1500ms even in control subjects, therefore, limiting conclusions regarding the ability to follow an instruction. Furthermore, a clinically diagnosed VS patient exhibited EEG responses indicative for MCS.


CONCLUSIONS
Results indicate that MCS patients are still able to process an observed motor behavior on a basic sensory and perhaps even pre-motoric level, but seem not to be capable of "mirroring" the movement like healthy participants.


CONCLUSIONS
"Real-world" tasks as presented here carry the potential to identify residual cognitive functioning in DOC patients and may ultimately help to lower misdiagnosis rates.
Department of Psychology, Laboratory for Sleep and Consciousness Research, University of Salzburg, Austria.
Julia
J
Lechinger
Nicole
N
Chwala-Schlegel
Robert
R
Fellinger
Johann
J
Donis
Gabriele
G
Michitsch
Gerald
G
Pichler
Manuel
M
Schabus
D000328:Adult; D000368:Aged; D000513:Alpha Rhythm; D001611:Beta Rhythm; D003244:Consciousness Disorders / Q000209:etiology / Q000503:physiopathology / Q000523:psychology*; D003627:Data Interpretation, Statistical; D004569:Electroencephalography; D005260:Female; D006225:Hand / Q000502:physiology; D006801:Humans; D007092:Imagination; D008297:Male; D008875:Middle Aged; D009068:Movement; D009778:Occipital Lobe / Q000503:physiopathology; D010296:Parietal Lobe / Q000503:physiopathology; D011597:Psychomotor Performance; D013826:Theta Rhythm; D055815:Young Adult