Reliance on advance information and movement sequencing in huntington's disease

Abstract

To identify the focus of impairment in the performance of sequential movements in Huntington's disease (HD) patients, the extent of their reliance on external advance information was examined. Twelve patients with HD and their age-matched controls performed a series of button-presses at sequential choice points along a response board. A sequential pathway was designated, and with each successive button press, advance visual information was systematically reduced to various extents in advance of each move. HD patients, like previously studied parkinsonian patients, were particularly disadvantaged with high levels of reduction in advance information, and as a consequence, both their initiation and execution of movements progressively slowed with each successive element in the response sequence. The pattern of results was not affected whether or not patients were taking neuroleptic medication, nor did performance on a variety of cognitive measures correlate with motor performance. Control subjects' performance, on the other hand, remained constant in terms of both initiation and execution with each of the three levels of reduction in advance information. We conclude that HD patients, like parkinsonian patients, who also suffer from a basal ganglia (BG) disorder, require external visual cues to sequence motor programs effectively. Our findings suggest that with HD there may be abnormalities in a central mechanism that controls switching between movement segments within an overall motor plan. The BG, which provide internal cues necessary for component sequencing, may be disrupted, thereby impairing the ability to use such internally generated cues to guide movement.

Control of manipulative forces during unimanual and bimanual tasks in patients with Huntington’s disease

“…The unstable planning of manipulative forces for HD patients when moving rhythmically hand-held objects extends previous findings of disturbed spatiotemporal behavior during bimanual activities (Hefter et al 1987;Johnson et al 2000) and sequential movements (Agostino et al 1992;Georgiou et al 1995). Overall, the present data demonstrate that regulation of movement components in unimanual and bimanual actions is disrupted in HD, resulting in modulated motor behavior.…”

Open interconnected model of basal ganglia‐thalamocortical circuitry and its relevance to the clinical syndrome of Huntington's disease

“…136 A similar pattern was seen in the second task, namely, HD patients' down time and movement time were particularly prolonged at the high information reduction condition, in which information regarding the next button press was provided after the release of the previous button. 138 Finally, in the second task, HD patients had prolongation of down time and movement time comparable to those in the first task, 138 whereas PD patients showed an opposite pattern, i.e., a dramatic prolongation of movement time with relatively mild prolongation of down time. 151 Bradshaw and colleagues 138,151,153 concluded that both patient groups are deficient in sequencing motor programs effectively under conditions in which external cues are not available, as reflected in prolongation of movement preparation time (down time) and movement execution time (movement time) under these conditions.…”

“…138 Finally, in the second task, HD patients had prolongation of down time and movement time comparable to those in the first task, 138 whereas PD patients showed an opposite pattern, i.e., a dramatic prolongation of movement time with relatively mild prolongation of down time. 151 Bradshaw and colleagues 138,151,153 concluded that both patient groups are deficient in sequencing motor programs effectively under conditions in which external cues are not available, as reflected in prolongation of movement preparation time (down time) and movement execution time (movement time) under these conditions. This conclusion is consistent with the view that PD patients have difficulties in the initiation and execution of movements, particularly when no external guidance is available.…”

Early Huntington’s disease affects movements in transformed sensorimotor mappings

“…Impairments in voluntary movement appear early in HD and are often similar to those seen after damage to premotor or prefrontal cortex. HD patients show problems planning and selecting movements especially when response selection requires attention such as in sequential responses, novel contexts or when interference from competing responses is present (Agostino, Berardelli, Formica, Accornero, & Manfredi, 1992;Bradshaw et al, 1992;Curra et al, 2000;Georgiou, Bradshaw, Phillips, Chiu, & Bradshaw, 1995;Girotti, Marano, Soliveri, Geminiani, & Scigliano, 1988;Gordon, Quinn, Reilmann, & Marder, 2000;Jahanshahi, Brown, & Marsden, 1993;Phillips, Chiu, Bradshaw, & Lansek, 1995;Sprengelmeyer, Lange, & Homberg, 1995;Thompson et al, 1988).…”