Impairment of individual finger movements in Parkinson's disease

Abstract

By analyzing the kinematics of repetitive, constant-amplitude, finger oppositions, we compared the impairment of individual and nonindividual finger movements in patients with Parkinson's disease. In one task, subjects tapped only the index finger against the thumb (individual oppositions); in the other task, they tapped all four fingers together against the thumb pad (nonindividual oppositions). We used an optoelectronic motion analysis system to record movements in three-dimensional space and recorded three 5-second trials for each task. We counted how many finger oppositions subjects performed during each trial and measured the duration and amplitude of the flexions and extensions. We also calculated the duration of the pauses after flexion and extension. We assessed the deterioration of motor performance in patients by investigating the changes in speed and amplitude with task completion. During both tasks, normal subjects and patients performed finger flexions faster than extensions, and they invariably paused longer after flexion than after extension. Patients performed individual and nonindividual finger movements slowly and with reduced amplitude. Patients were disproportionately slow during flexion and in switching from flexion to extension. Movement slowness increased as finger oppositions progressed but predominantly when patients had to move fingers individually. In conclusion, in patients with Parkinson's disease, the motor performance deteriorated with task completion more during individual than during nonindividual finger movements. Parkinson's disease, therefore, impairs individual finger movements more than gross hand movements. This distinction reflects the finer cortical control needed to promote and sustain this highly fractionated type of motor output.

Increased bradykinesia in Parkinson’s disease with increased movement complexity: elbow flexion–extension movements

“…Results demonstrated that in the more advanced stages of PD, neurotransmitters in a particular module may be depleted to such an extent that further movement by that module is completely prevented until the neurotransmitters have been allowed to re-accumulate to a certain level. This may explain the increased inter-segment delay observed in PD patients between movement segments of a sequential movement (Berardelli et al 2001;Agostino et al 2003;Kelly and Bastian 2005).…”

“…PD patients exhibit abnormal pauses between movement segments and a more pronounced movement time when a task is performed within a sequence of moves (Suri et al 1998;Berardelli et al 2001). Several mechanisms have been proposed to explain the extra deficits observed in complex movements, such as insufficient dopamine resources for multiple simultaneous movements, difficulty in switching between movement segments due to impaired force control, interference from competing motor programs, and impaired preparation of movement sequences (Agostino et al 2003;Levy et al 2002). Cutsuridis and Perantonis (2006) have developed a basal ganglia-corticospinal network model for control of voluntary arm movements by incorporating dopaminergic innervation of cells in the cortical and spinal components of the circuit.…”

Finger tapping movements of Parkinson’s disease patients automatically rated using nonlinear delay differential equations

“…Moreover, the motor performance of PD patients degrades with task completion far more easily during sequential opposition of individual finger movements than during non-individual finger oppositions. 28 The dynamics underlying movements of PD patients was, therefore, investigated by recording 10 s bouts of individual finger tapping movements. These movements were repetitive index-thumb oppositions, instructed to be of large constant amplitude, produced smoothly and rapidly.…”

Balancing out dwelling and moving: optimal sensorimotor synchronization

“…Second, our results point to the central role of dwelling in the context of temporal synchronization. Interestingly, several clinical studies have reported an increased DT in sequential and repeated movements in Parkinson's disease patients compared with control subjects (Agostino et al 2003;Brontë-Stewart et al 2000;Jones et al 1992;Onla-or and Winstein 2001). Franco and Turner (2012) have shown that the selective blockage of dopamine transmission in monkey sensorimotor striatum leads to increased waiting times in the transition between cued reaching movements and selfinitiated, return movements.…”