Recruitment of attentional resources during visuomotor tracking: effects of Parkinson's disease and age

• Published in: Brain research. Cognitive brain research Vol. 21; no. 1; pp. 77 - 86
• Main Authors: Hocherman, Shraga, Moont, Ruth, Schwartz, Miguel
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01-09-2004; Elsevier Science
• Subjects: Adult and adolescent clinical studies; Aged; Aging - psychology; Attention; Attention - physiology; Biological and medical sciences; Degenerative and inherited degenerative diseases of the nervous system. Leukodystrophies. Prion diseases; Executive functions; Female; Humans; Learning - physiology; Male; Medical sciences; Middle Aged; Neurology; Organic mental disorders. Neuropsychology; Parkinson Disease - psychology; Parkinson's disease; Parkinsons Disease; Photic Stimulation; Psychology. Psychoanalysis. Psychiatry; Psychomotor Performance - physiology; Psychopathology. Psychiatry; Recruitment, Neurophysiological - physiology; Visuomotor coordination; Disorders of the nervous system; Executive functions; Visuomotor coordination; Parkinson's disease; Attention; Human; Nervous system diseases; Executive function; Central nervous system disease; Parkinson disease; Degenerative disease; Cognition; Motricity; Visuomotor tracking; Cerebral disorder; Extrapyramidal syndrome
• ISSN: 0926-6410
• DOI: 10.1016/j.cogbrainres.2004.05.008

The ability to recruit attentional resources during distracted tracking was studied in 19 moderate PD patients, 21 healthy elderly subjects and 20 young controls. All subjects tracked a 1-cm circle that moved across a computer screen along a sinusoidal path (training) and along a circular path (testing). Tracking consisted of maintaining a dot cursor within the target by moving an unseen manipulandum across a digitizing tablet. Distraction consisted of adding one or three, colored 12-mm circles that moved around and intersected with the target circle, and one or three dots that moved around and intersected with the subject-controlled cursor. The performance of tasks with a low level of distraction (one dot and one circle distractor) and of tasks with a high level of distraction (three dot and three circle distractors) was compared to performance with no distraction.
The elderly and young controls did not differ in the baseline task. Both groups surpassed the patients, who failed to keep pace with the target, despite preserved ability to attain the necessary movement speed. Under a low level of distraction, the ability to adjust the direction of hand movement diminished in both control groups, but task management was unaltered. In the patients adjustment of hand movement direction lowered, as in the controls, but task management reduced significantly. Under a high level of distraction, all groups showed further decrement in both aspects of task performance.
We conclude that PD, but not age, significantly reduces the attentional resources required for administrative control of tracking, which are associated with prefrontal function.