Affiliations: Neuropsychology Unit, Department of Neurology, Geneva
University Hospitals and Medical School, Switzerland | Neurology Outpatients' Clinic, Department of
Neurology, Geneva University Hospitals and Medical School, Switzerland | Laboratory of Experimental Neuropsychology, Department
of Neurology, Geneva University Hospitals and Medical School, Switzerland | Faculty of Psychology and Sciences of Education,
University of Geneva, Switzerland
Note: [] Corresponding author: Dr Blaise Christe, Unit of
Neuropsychology, Department of Neurology, Geneva University Hospitals, Rue
Micheli-du-Crest 24, 1211 Genève 14, Switzerland. Tel.: +41 022 372 83
03; Fax: +41 022 372 82 99; E-mail: blaise.christe@hcuge.ch
Abstract: In this study, we developed a digitizing tablet-based instrument for
the clinical assessment of human voluntary movements targeting motor processes
of planning, programming and execution. The tool was used to investigate an
adaptation of Fitts' reciprocal tapping task [10], comprising four
conditions, each of them modulated by three indices of difficulty related to
the amplitude of movement required. Temporal, spatial and sequential
constraints underlying the various conditions allowed the intricate motor
processes to be dissociated. Data obtained from a group of elderly healthy
subjects (N=50) were in agreement with the literature on
motor control, in the temporal and spatial domains. Speed constraints generated
gains in the temporal domain and costs in the spatial one, while spatial
constraints generated gain in the spatial domain and costs in the temporal one;
finally, sequential constraints revealed the integrative nature of the
cognitive operations involved in motor production. This versatile instrument
proved capable of providing quantitative, accurate and sensitive measures of
the various processes sustaining voluntary movement in healthy subjects.
Altogether, analyses performed in this study generated a theoretical framework
and reference data which could be used in the future for the clinical
assessment of patients with various movement disorders, in particular
Parkinson's disease.
Keywords: Motor control, clinical assessment, cognitive approach, speed-accuracy trade-off
