- Visuomanual pointing and clicking in children and adolescents. Kudlinski, Cyril; Jouen, François; Molina, Michèle. ISSBD, July, 2012. Edmonton, Alberta, Canada.
- Motor imagery for walking and drawing in children. Guilbert, Jessica; Jouen, François; Molina, Michèle. ISSBD, July, 2012. Edmonton, Alberta, Canada.
Visuomanual pointing and clicking in children and adolescents. Kudlinski, Cyril; Jouen, François; Molina, Michèle. ISSBD, July, 2012. Edmonton, Alberta, Canada.
Introduction
Fitts’ paradigms (Fitts, 1954) are commonly used to study visuomanual pointing in 2D environment. They allow to determinate that movement time is related to index of difficulty (ID) of the task such that MT= a + b log2(2A/W). Lambert & Bard (2004) used a Fitts’ task to study the development of visuomanual pointing with a computer mouse in children aged of 6, 8 and 10 years. Children were asked to point and click on target of three different sizes while the distance between targets remained constant. Authors observed that precision, efficiency and fluency of visuomanual pointing are clearly improved between 6 and 10 years. This developmental progress parallels the one observed for tridimensional movements. However, in contradiction with 3D pointing studies, authors observed that 10 year-old children did not reach adult-like performances. Two questions remain: 1°) to know whether the results obtained by Lambert & Bard could be extended to a situation in which the width of the target and the distance between the target varied inducing thus a larger sample of ID and 2°) to investigate the development of visuomanual pointing after 10 years.
Method
218 children and adolescents ranging from 5 and 14 years and 25 adults took part in an experiment using a Fitts’ paradigm. A pointing task was proposed to the participants. On a screen of a laptop, two verticals parallels and symmetric bars were presented: a blue target bar and a reference yellow bar. Participants were asked to click as fast and accurately as possible on the blue bar. As soon as a click was done, the bars reversed their position. 20 ID were successively and randomly presented resulting from the combination of 4 distances and 5 widths (from 2.87 bits to 7 bits). Each participant performed 5 clicks per ID.
Results
Movement time (MT) and position of cursor’s mouse were recorded. Results revealed that MT decreases with age. Linear regression analyses showed that from 5 years children MT increases linearly with IDs and conforms to Fitts’ law. Analysis of kinematic cues revealed a developmental sequence according to which kinematic templates do not differ from adults for the ratio between effective trajectory and minimum trajectory by 10 years, for the number of strokes by 11 years, for the first stroke length by 12 years and for the average velocity by 13 years.
References
Fitts, P.M., (1954). The information capacity of the human motor system in controlling the amplitude of movement. Journal of Experimental Psychology 47 (6), 381–391.
Lambert, J., Bard C., (2005) Acquisition of visuomanual skills andimprovement of information processing capacities in 6 to 10 year old children performing a 2D pointing task. Neurosciences Letter 377:1–6.
Motor imagery for walking and drawing in children. Guilbert, Jessica; Jouen, François; Molina, Michèle. ISSBD, July, 2012. Edmonton, Alberta, Canada.
Introduction:
Motor imagery (MI) refers to the capacity to mentally rehearse functional movement without motor execution. According to the theory of action simulation proposed by Jeannerod (1994, 2001, 2003), MI capacity can be considered as a conscious motor prediction during which participants use internal models of action to achieve timing information and thus simulate the temporal unfolding of a covert action. Developmental studies have revealed that timing correspondence between executed and imagined movements is rather weak at 6 and 8 years but considerably improved at 10 years as a consequence of the refinement of internal models of action. The aim of the present experiment was to evaluate whether by 10 years, refinement and stabilization of internal forward models of action could make possible the generalization of MI across different motor tasks.
Method:
Sixty-six 6-, 8- and 10 years children were observed in a mental chronometry paradigm according to which, durations for executed (E) and imagined (I) actions were compared for a walking task and a drawing task. All children performed the executed action before the imagined action. For each task, each child had to successively perform a short and a long distance. The order of presentation of distances was counterbalanced across participants.
Results and Discussion:
Results revealed that significant Pearson’s correlations between E and I durations for drawing were observed in 6, 8, and 10 year-old children for both short and long distances. Significant correlations between E and I walking durations were observed whatever the distances for the 8 and the 10-year-old children but not for the 6 year-old-children. An ANOVA was also conducted to evaluate the effects of age and experimental conditions on time invariance. For this analysis, a ratio (E/I) was calculated for each participant. A ratio close to 1.0 indicates accurate MI skills. ANOVA revealed that whatever the task and the distance to be performed, E/I ratios progressively increase between 6 years and 10 years and tend to the 1.0 critical value around 10 years. Moreover, E/I ratios also depend on the task (walking versus drawing) in 6 and 8 years but not in 10 years. Taken together, these results suggest that by 10 years, improvement of internal representations of movement sustains accurate MI capacity for various motor tasks.
References:
Jeannerod, M. (1994). The Representing Brain: Neural Correlates of Motor Intention and Imagery. Behavioral and Brain Sciences, 17(02), 187-202.
Jeannerod, M. (2001). Neural Simulation of Action: A Unifying Mechanism for Motor Cognition. Neuroimage, 14(1), S103-S109.
Jeannerod, M. (2003). The mechanism of self-recognition in humans. Behavioural Brain Research, 142(1-2), 1-15.