Showing papers by "Jerome N. Sanes published in 1983"
TL;DR: Findings demonstrate that peripheral kinesthetic disturbances modify movement trajectory and end point error, with small movements being more affected than large movements.
Abstract: This study was carried out to test the hypothesis that the magnitude of perturbation-induced disruption of active movement depends upon the size of the active movement, with small movements being more disrupted than large ones. Human subjects performed pronating or supinating arm movements of 3 degrees, 10 degrees, and 30 degrees in a discrete visual tracking task. When the movements were briefly stopped or reversed, the resultant errors in trajectory and static position (expressed relative to the movement size) were greater for small as compared to large movements. These findings demonstrate that peripheral kinesthetic disturbances modify movement trajectory and end point error, with small movements being more affected than large movements.
123 citations
TL;DR: A consideration of the anatomical substrate for each reflex component, together with some other data in the literature, suggests that reflex sensitization occurred in the efferent limb of this brain stem reflex while simultaneously habituation occurred in its central link.
Abstract: The supraorbital branch of the right trigeminal nerve was stimulated with trains of electric shocks, 10 in each train, with interpulse intervals of 1, 2, or 5 sec. Electromyographic reflex activity in the palpebral musculature was measured to each pulse in the train. Each response consisted of two components, a fast brief ipsilateral burst (R1) and a slower prolonged bilateral burst (R2). Over the 10-pulse series, the amplitudes of R1 increased in strength (sensitization), whereas the allied R2 amplitudes declined (habituation). Both of these effects were enhanced as the interpulse interval was reduced. A consideration of the anatomical substrate for each reflex component, together with some other data in the literature, suggests that reflex sensitization occurred in the efferent limb of this brain stem reflex while simultaneously habituation occurred in its central link.
39 citations
Journal Article•
TL;DR: It is concluded that there is at present no effective substitute for clinical procedures, although the convenience and future potential of objective measurement justify the further development of such systems for use in the experimental study of PD.
Abstract: Objective measurements of movement time, reaction time, and gait were compared with a clinical rating performed at the same times on several occasions in 10 patients with Parkinson's disease (PD) Positive correlations between objective measures and clinical evaluation were demonstrated Movement time was the single most useful index of motor deficit, but no objective tests were more sensitive than clinical evaluations in the detection of motor disorder It is concluded that there is at present no effective substitute for clinical procedures, although the convenience and future potential of objective measurement justify the further development of such systems for use in the experimental study of PD
32 citations
Journal Article•
22 citations