Performance on a mirror-drawing task by non-right-handers

Effects of color cues on eye-hand coordination training with a mirror drawing task in virtual environment

Mirror drawing is a motor learning task that is used to evaluate and improve eye-hand coordination of users and can be implemented in immersive Virtual Reality (VR) Head-Mounted Displays (HMDs) for training purposes. In this paper, we investigated the effect of color cues on user motor performance in a mirror-drawing task between Virtual Environment (VE) and Real World (RW), with three different colors. We conducted a 5-day user study with twelve participants. The results showed that the participants made fewer errors in RW compared to VR, except for pre-training, which indicated that hardware and software limitations have detrimental effects on the motor learning of the participants across different realities. Furthermore, participants made fewer errors with the colors close to green, which is usually associated with serenity, contentment, and relaxation. According to our findings, VR headsets can be used to evaluate participants' eye-hand coordination in mirror drawing tasks to evaluate the motor-learning of participants. VE and RW training applications could benefit from our findings in order to enhance their effectiveness.

Sensorimotor adaptation in Parkinson's disease: evidence for a dopamine dependent remapping disturbance

Sensorimotor adaptation is thought to involve a remapping of the kinematic and kinetic parameters associated with movements performed within a changing environment. Patients with Parkinson's disease (PD) are known to be affected on this type of learning process, although the specific role of dopamine depletion in these deficits has not yet been elucidated. The present study was an attempt to clarify whether dopamine depletion in PD may directly affect the capacity to internally reorganize the visuomotor remapping of a distorted environment. Fourteen PD patients were tested twice, while they were treated and while they were withdrawn from their regular levodopa treatment. Fourteen control subjects were also enrolled and tested twice. Two parallel forms of the Computed Mirror Pointing Task (CMPT), requiring making a reaching movement in a visually transformed environment (mirror inversion), were administered to each participant. Each of them had to perform 40 trials at each of the 2 testing sessions. At each trial, sensorimotor adaptation was evaluated by the initial direction angle (IDA), which reflects the direction of movement before any visually guided readjustment. Results revealed no IDA difference at baseline, between control subject and PD patients, whether they were treated or not. In all group, IDA values at that time were large, reflecting a tendency to make movements according to the real life visuomotor mapping (based on the natural direct vision). However, striking differences appeared during sensorimotor learning, in that IDA reduction along trials was poorer in patient not treated with levodopa than both control subjects and the same PD patient treated with levodopa. No difference was observed between the treated PD patients and control subjects. Given that IDA is thought to reflect the internal representation of the visuomotor mapping, it is concluded that dopamine depletion in PD would affects sensorimotor adaptation, in that it facilitates old and poorly adapted movements (real life mapping), instead of new and more adapted ones (mirror transformed mapping).

Laterality and accident proneness: A study of locomotive drivers

This study attempted to find the association between four measures of laterality (handedness, footedness, eyedness, and earedness) and accident proneness in locomotive drivers. The Sidedness Bias Schedule was administered to a sample of 80 locomotive drivers to ascertain their preferential bias. Their accident records were also available. Positive correlations were mostly found between the measures of hand, foot, ear, and eye dominance. Analyses suggested that there was a higher accident rate among left-handers and left-footers, with multiple regression unable to determine whether handedness or footedness was related more strongly to accident proneness. However, it was clear that accident rate was primarily associated with direction of lateralisation, and not with degree of lateralisation. Drivers with left-handedness were more likely to be involved in accidents, and it is possible that that may be related to the design of the locomotive cabs.

Bilateral transfer of skill in left- and right-handers

Bilateral transfer of skill as a function of speed and accuracy was examined in self-classified left-handed (n=20) and right-handed (n=40) subjects. Two transfer conditions (non-preferred to preferred hand, preferred to non-preferred hand) were manipulated in a mirror-drawing task and data were treated with Groups (left, right hander) x Transfer type (speed, accuracy) x Side (non-preferred to preferred hand, preferred to non-preferred hand) mixed factorial ANOVA with repeated measure in Transfer and Side factors. Percentage of bilateral transfer (First 5 trials-Last 5 trials/First 5 trials x 100) was the dependent measure. Left and right-handers did not differ in the magnitude of bilateral transfer. Bilateral transfer was greater (a) from non-preferred to preferred side as compared to the reverse, and (b) was greater with respect to speed but not with accuracy.

Immediate and delayed bilateral transfer of throwing accuracy in male and female children

In the present study, an attempt was made to examine the nature and persistence of bilateral transfer of a throwing skill for a large sample of male and female children. One hundred sixty children ages 6, 8, 10, and 12 years were randomly assigned to either an experimental or control group with an equal number of boys and girls in each group. The experiment lasted 2 days and consisted of a pretest, a practice phase, an immediate transfer test, and a delayed transfer test. On the pretest, each participant performed 10 trials of a novel one-hand throwing task. Following the pretest, participants in the experimental group practiced the skill with the hand opposite the one used during the pretest until they had successfully reached a designated criterion for their age. Participants in the control group performed a balancing activity. Following the practice phase, all participants performed immediate (10 min later) and delayed (24 hr later) transfer tests under the same conditions as the pretest. The results revealed no group differences on the pretest but significantly higher throwing accuracy for the experimental group than the control group on both transfer tests. In addition, boys' throwing accuracy was significantly superior to the girls. It was concluded that bilateral transfer of throwing accuracy can be both a temporary and relatively persistent phenomenon for children and the superior throwing accuracy for boys is consistent with similar gender differences in throwing distance and throwing velocity (Thomas & French, 1985).