Effect of directed attention in Huntington's disease.
This experiment sought to ascertain whether overt gaze (i.e., directed attention) would influence attentional performance in Huntington's disease (HD), via the use of a vibrotactile choice reaction time procedure involving biased probabilities of event occurrence. Subjects looked (i.e., direct gaze) either at the hand receiving the most (expected) vibrations, or the hand less often stimulated (the unexpected), for both crossed and uncrossed arm postures. Patients with HD showed performance advantages when directing attention (i.e., gaze) at the responding hand, especially for expected events. Patients with HD, however, were not sensitive to distributions of event probability in the uncrossed arm posture, nor when looking away from the responding hand. With the crossed arm posture, and when directing attention at the expected side, patients with HD became more sensitive to distributions of event probability. In HD, there may be a disruption of fronto-striatal circuitry on both cortical and subcortical levels which may account for impairments both in holding and shifting attention.
Georgiou
N
N
Neuropsychology Research Unit, Monash University, Clayton, Australia.
Bradshaw
J L
JL
Phillips
J G
JG
Chiu
E
E
D000328:Adult; D001288:Attention / Q000502:physiology*; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D006816:Huntington Disease / Q000523:psychology*; D008297:Male; D008875:Middle Aged; D011187:Posture / Q000502:physiology; D011569:Psychiatric Status Rating Scales; D011930:Reaction Time / Q000502:physiology; D014110:Touch / Q000502:physiology; D014732:Vibration