Initiation and execution of movement sequences in those suffering from and at-risk of developing Huntington's disease

Abstract

Recent research has shown that Huntington's disease (HD) causes problems in the initiation and execution of movement (akinesia, bradykinesia): information which is useful in documenting the functional progression of the disease. The present experiment used a sequential movement task to characterize such impairments. Eighteen patients diagnosed as suffering from HD, and a similar number of matched At-Risk (AR) and Normal control subjects, performed sequential button pressing tasks, under varying amounts of visual advance information. Specific dimensions of motor control were examined (hand, direction). Movement initiation and in particular movement duration were useful indicators of the functional progression of the disease, and also detected anomalies of performance in some AR individuals. Impaired motor programming was indicated by patients' difficulty in initiating movements in the absence of external visual cues, and their problems in utilizing advance information to control movement. Patients had specific deficits in initiating movements with the nonpreferred hand, and directional movement asymmetries were accentuated. The results suggest that HD causes difficulties at three discrete levels: in utilizing advance information, in the initiation and in the spatial representation of movement.

Early Huntington’s disease affects movements in transformed sensorimotor mappings

“…More work will of course be needed to disentangle these contributions if possible. This hypothesis is compatible with impairments in attention and choice responses in these patients (Bradshaw et al, 1992;Hefter, Homberg, Lange, & Freund, 1987;Jahanshahi et al, 1993;Lawrence et al, 1996). The results are similar to the problems shown by HD patients in the Stroop task, in which an overlearned skill (word reading) interferes with an attention-demanding voluntary response (rapid color naming) (ex: Snowden et al, 2001).…”

“…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).…”

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

“…Particularly revealing in the present context is a set of experiments by Bradshaw and colleagues 136,[151][152][153] comparing the performance of HD and PD patients on two versions of a sequential button-pressing task. In both tasks, information about the next button to be pressed was provided by illuminating it.…”

“…136,153 However, whereas PD patients improved when advance information was provided, no such improvement was seen in HD patients. HD patients, and to a much lesser degree PD patients, had longer movement time.…”

“…1 Bradykinesia is another fundamental, albeit less recognized, feature of the motor deficit in HD, seen already in the early stages of the disease. 127,[135][136][137][138][139][140][141][142][143][144] It was suggested 91,144 that bradykinesia in the early stages results from underactivity of the direct pathway of the motor circuit, similar to the mechanism underlying bradykinesia in Parkinson's disease (PD). 1,5,16 However, in HD the direct pathway of the motor circuit degenerates only in later stages.…”