The goal of present experiment was to test whether different speed-accuracy paradigms outcomes (time minimization and time matching) were due to different temporal and spatial task constraints. Fifteen participants twice performed 100 trials of time minimization and time matching tasks with the yoked temporal and spatial requirements (criterion time and target width). The results showed that performing an aiming movement under the same spatial and temporal constraints resulted in similar outcomes with distributional properties (skewness and kurtosis) being slightly affected by practice effects. There was a trade-off in the information entropy for space and time (temporal information entropy decreased as spatial information entropy increased) with practice. Nevertheless, the joint space-time entropy of outcome did not change across tasks and conditions—revealing a common level of space-time entropy between these two categories of aiming tasks. These findings support the hypothesis that under the same spatial and temporal constraints the movement speed-accuracy function shares the same properties independent of task category.
Tsung-Yu Hsieh, Matheus M. Pacheco and Karl M. Newell
Shih-Chiung Lai, Tsung-Yu Hsieh and Karl M. Newell
Information entropy of the joint spatial and temporal (space-time) probability of discrete movement outcome was investigated in two experiments as a function of different movement strategies (space-time, space, and time instructional emphases), task goals (point-aiming and target-aiming) and movement speed-accuracy constraints. The variance of the movement spatial and temporal errors was reduced by instructional emphasis on the respective spatial or temporal dimension, but increased on the other dimension. The space-time entropy was lower in targetaiming task than the point-aiming task but did not differ between instructional emphases. However, the joint probabilistic measure of spatial and temporal entropy showed that spatial error is traded for timing error in tasks with space-time criteria and that the pattern of movement error depends on the dimension of the measurement process. The unified entropy measure of movement outcome in space-time reveals a new relation for the speed-accuracy function.
Yeou-Teh Liu, Tsung-Yu Hsieh and Karl M. Newell
Recent studies have shown more than one time scale of change in the movement dynamics of practice. Here, we decompose the drift and diffusion dynamics in adaptation to performing discrete aiming movements with different space-time constraints. Participants performed aiming movements on a graphics drawing board to a point target at 5 different space-time weightings on the task outcome. The drift was stronger the shorter the time constraint whereas noise was U-shaped across the space-time conditions. The drift and diffusion of adaptation in discrete aiming movements varied as a function of the space-time constraints on performance outcome and the spatial, temporal, or space-time measure of performance outcome. The findings support the postulation that the time scale of movement adaptation is task dependent.
Shu-Shih Hsieh, Yu-Kai Chang, Chin-Lung Fang and Tsung-Min Hung
The current study examined the effects of acute resistance exercise (RE) on adult males’ attention control. Eighteen younger males (23.9 ± 2.3 years) and 17 older males (66.4 ± 1.2 years) were recruited. Participants underwent a RE session and a reading session in a counterbalanced order. RE protocol required individuals to perform two sets of 10 repetitions of eight exercises using weights set at 70% of 10-repetition maximum. Attention control was assessed by go/no-go SART with intraindividual variability in reaction times (IIV in RT), in addition to reaction time and accuracy, employed as measures of attention control. Results indicated that IIV in RT was smaller following RE sessions than after reading sessions for both age groups. In addition, RTs were shorter after the exercise session. These findings suggest that RE enhances attention control in adult males and that the size of this effect is not moderated by age.