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

Abstract

The aim of the study was to investigate gripload force regulation in Huntington's disease (HD) patients as compared to control subjects during the performance of a manipulative task that required rhythmical unimanual or bimanual isodirectional/non-isodirectional actions in the sagittal plane. Results showed that the profile of grip-load ratio force was characterized by maxima and minima that were attained at upward and downward hand positions, respectively. Minimum force ratio was higher in patients than in controls, which points to an elevated baseline that may be related to the inherent bradykinesia observed in HD. Maximum force ratio was also increased in patients, but this effect depended on the performance condition, with largest amplifications occurring during non-isodirectional movements. The latter rescaling may be associated with the complexity of the coordination mode and its asymmetrical load characteristics. In addition, the temporal delay between the grip and load force peaks was augmented in patients versus controls, indicating a disturbed coupled activation of both forces. Furthermore, the interval was largest during nonisodirectional movements followed by isodirectional and unimanual movements, which denotes that the grip-load force coupling deteriorated as a function of coordinative complexity. Together, these data indicate a deficit in the grip-load force constraint due to HD and illustrate the degrading effect of striatal dysfunction on (bi)manual manipulative function.

Inter-limb coupling during diadochokinesis in Parkinson's and Huntington's disease

“…HD patients have previously been shown to have very little deficit in simple bimanual tasks (Johnson et al, 2000;Duval et al, 2009). Rather, they exhibit marked decrease in motor performance as the bimanual task becomes more complex (Johnson et al, 2000;Serrien et al, 2002). Specifically, Brown et al (1993) demonstrated that while HD patients did exhibit deficits in bimanual motor performance, these deficits were smaller than those observed in PD patients.…”

Basal ganglia mechanisms underlying precision grip force control

“…Similar to PD and dystonia, HD is associated with elevated grip force levels (Schwarz et al, 2001; Serrien et al, 2001; Serrien et al, 2002a) and slowness of grip force development (Serrien et al, 2001). Grip and load force coupling is also disturbed in HD, and these disturbances increase with task complexity (Serrien et al, 2002a).…”

Evaluation of a method for bimanual testing coordination of hand grip and load forces under isometric conditions

“…Excessive GF that is poorly coordinated in time with external load is typical for patients with neurological impairments, such as stroke [16], HungtingtonÕs disease [19], cerebellar lesions [20], cerebellar atrophy [15], or ParkinsonÕs disease [8].…”