Bimanual Tracking Research Articles

Transfer of Motor Learning in a Visuomotor Tracking Task for Healthy Old and Young Adults

Using a continuous bimanual tracking task with three different movement speeds, we examined motor learning and transfer in older adults. Three groups of subjects within each age group learned only one particular trajectory during training of 40 trials, while the other two trajectories were not practiced during this period. Motor learning (measured as absolute and relative reduction in tracking error) was identified in all subjects. The most important finding was that motor learning was present even for the trajectories that were not practiced to almost the same degree as for practiced trajectories and motor skills for visuomotor tracking show the same amount of improvement and transfer in young and older adults.

Acquisition of motor skill after bilateral medial temporal-lobe excision

Abstract The acquisition of selected motor skills was studied in a 40-year-old man with a severe amnestic syndrome resulting from a bilateral medial temporal-lobe resection carried out 13 years before. On Rotary Pursuit, Bimanual Tracking, and Tapping, his scores improved from session to session, and on the one task where it was feasible to retest several days after the end of training (Rotary Pursuit), he showed complete retention. These results imply that motor learning can be mediated by brain structures still intact in this patient. The additional finding that he was inferior to normal men of his age on two tasks, in both initial and final levels of performance, is attributed to his relatively long reaction time rather than to the memory deficit.

Workload and Strategic Adaptation under Transformations of Visual-Coordinative Mappings

Six right-handed male volunteers performed a bi-manual pursuit tracking task. Unknown to the subject, the mapping between both the absolute and relative motions of each control lever changed between trials, and could also change within a trial. There were four conditions which remained constant within a trial and four others which switched between combinations of the first four mappings. These eight total mappings could be performed under either a fast or slow target speed giving sixteen possible conditions, the order of administration of which was randomized across the subjects. Performance was assessed through the use of root mean square error (RMS) and percent time-on-target (TOT). Workload was derived from subjective report using the NASA Task-Load Index. Performance results differentiated three different groups within the mappings. The first group represented conditions in which despite scaling factors, the movement of the cursor remained consistent with the movement of the controls and was directly mapped. The second group, consisting of only two conditions, also presented internal consistency except that the movements of the cursor were mirrored in the movements of the controls, a direct but inverted map. The third group represented those conditions in which at least one period of performance decoupled the actions of the two controls. In general, workload distinguished the ordering of difficulty of the conditions, except that there was evidence of dissociation between performance and subjective evaluation in the three most difficult decoupled conditions. Verbal report of performer strategic behavior was elicited. Each line of evidence is considered in the attempt to understand how subjects explored the perceptual-motor space for strategic solutions when presented with the autonomy to do so.

Bimanual co-ordination in callosal agenesis and partial commissurotomy

Studies [Preilowski, B.F.B. in Cerebral Localization, pp. 116-131, Springer, Berlin, 1975; Reynolds, D.M. and Jeeves, M.A. Neuropsychologia 12, 287-290, 1974] of bilateral motor coordination in commissurotomy patients pointed to the importance of direct interhemispheric integration for the fine regulation of the lower motor system within each hemisphere. When external visual feedback was withdrawn in the performance of a bimanual tracking task, partial commissurotomy patients, in whom the anterior portions of the callosum were cut, deviated significantly when drawing lines which required asymmetrical input from the two hands. The task devised by Preilowski was given to two adult acallosals, an 11 yr old acallosal boy, and an 11 yr old girl in whom the centre one-third of the corpus callosum had been sectioned. The acallosals performed in a manner similar to Preilowski's partial commissurotomy patients. The results were interpreted as confirming the interhemispheric integrative function of the corpus callosum. It is argued that they constitute further evidence for the existence of hemispheric dominance for motor control in acallosals. The partial commissurotomy patient did not differ in performance from normals. Her results were consistent with the view that it is the anterior parts of the callosum which are crucial for the interhemispheric integration of the lower motor system in each hemisphere.

Unimanual and Bimanual Control in a Compensatory Tracking Task∗

Abstract This paper reports an experiment comparing the unimanual and bimanual control performance of human operators in a compensatory tracking task. Two variables of the control system dynamics, the target wave frequencies and the delayed visual feedback (DVF) of operator's hand control motion were also investigated. Target wave frequencies of 0.067 Hz, 0.167 Hz and 0.383 Hz, and DVF of 0.0, 0.2, 0.4, 0.8 and 1.5 s were used. The experiment was divided into one practice session run over four days and one experimental session of two days for each of the six subjects in the study. A computer system was designed to generate target wave patterns, to measure hand control motions, to regulate DVF conditions, and to record task data, all on a real-time basis. The results indicate that unimanual tracking was significantly superior to the bimanual tracking under DVF conditions and higher levels of wave frequency, but not under the zero DVF or low wave frequencies. Tracking performance in general degraded as a fu...

Acquisition of motor skill after bilateral medial temporal-lobe excision

Abstract The acquisition of selected motor skills was studied in a 40-year-old man with a severe amnestic syndrome resulting from a bilateral medial temporal-lobe resection carried out 13 years before. On Rotary Pursuit, Bimanual Tracking, and Tapping, his scores improved from session to session, and on the one task where it was feasible to retest several days after the end of training (Rotary Pursuit), he showed complete retention. These results imply that motor learning can be mediated by brain structures still intact in this patient. The additional finding that he was inferior to normal men of his age on two tasks, in both initial and final levels of performance, is attributed to his relatively long reaction time rather than to the memory deficit.