Automatic processing dysfunction in Parkinson's disease.
Simultaneous measures of Event Related Potentials (ERP) and electrodermal activity (EDA) allow the delineation of ERPs that did, and did not, evoke an electrodermal 'Orienting Reflex' (OR). The OR is an automatic reflex invoked by novel or significant stimuli. Our group have developed a model to quantify electrodermal OR activity acquired in conventional late component ERP paradigms with short interstimulus intervals. Target late component (N100, P200, N200, P300) ERPs (acquired in an auditory oddball paradigm) and EDA was examined in 15 Parkinson's disease (PD) subjects and 50 normal controls. Single-trial target ERPs were averaged according to whether or not they elicited an electrodermal OR. Compared with controls, the PD group showed significantly decreased N100 and N200 amplitudes in the OR related ERPs ('Orienting ERPs'). These preliminary findings suggest that conventional late component ERPs can be delineated according to whether or not they evoked an OR. The 'orienting ERPs' in PD showed more significant disturbances compared with controls, than ERPs that did not evoke an OR.
Lagopoulos
J
J
Department of Neurology, Westmead Hospital, Sydney, NSW, Australia.
Gordon
E
E
Lim
C L
CL
Bahramali
H
H
Morris
J G
JG
Clouston
P
P
Li
W M
WM
Lesley
J
J
D000161:Acoustic Stimulation; D000328:Adult; D000368:Aged; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009949:Orientation; D010300:Parkinson Disease / Q000503:physiopathology*; D012016:Reference Values; D012018:Reflex; D012867:Skin / Q000294:innervation