Deficits in sensorimotor control during precise hand movements in Huntington's disease

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

“…During all performance conditions, HD patients as compared to control subjects overscaled their motor output, extending previous work on discrete unimanual tasks (Gordon et al 2000;Schwarz et al 2001;. With respect to the rhythmical unimanual and bimanual assignments examined in the present study, this implied an increased minimum and maximum force ratio.…”

“…The lack of coordinated behavior in HD is further manifested in the fine motor organization of object manipulation (Gordon et al 2000;Quinn et al 2001;Schwarz et al 2001;. In particular, grasp stability is disturbed in HD patients and an inappropriate degree of grip force (normal to the surface) is generated in relation to load force (tangential to the surface).…”

Quantifying feedforward control: a linear scaling model for fingertip forces and object weight

“…Johansson and colleagues initiated the examination of fingertip force coordination during object manipulation [see Johansson (1998) for review]. Their results have been used to study sensorimotor integration in healthy individuals, and their model has been found to be sensitive in detecting impairment in fine motor control in various patient populations (Fellows et al 1998;Gibbs et al 2008;Gordon et al 1997Gordon et al , 1999Schwarz et al 2001). It has been shown that the rate of change of load force before lifting an object is faster for a heavier weight than for a lighter weight in healthy individuals after one to three trials, resulting in a higher PLFR for a heavy object compared Fig.…”

Early Huntington’s disease affects movements in transformed sensorimotor mappings

“…In complex movements, they have problems making transitions between movement segments (Gordon et al, 2000;Quinn, Reilmann, Marder, & Gordon, 2001;Schwarz, Fellows, Schaffrath, & Noth, 2001). In simple visually-guided movements, HD patients show fewer precision problems.…”