Biomedical subjects

Nicolas Benguigui

Publications and source records attributed to Nicolas Benguigui.

5 recordsLinked to original sources

PubMed2006

The effect of aging and tennis playing on coincidence-timing accuracy.

This study examined the effect of tennis playing on the coincidence timing (CT) of older adults. Young, younger-old and older-old (20-30, 60-69, and 70-79 years old, respectively) tennis players and nonplayers were asked to synchronize a simple response (pressing a button) with the arrival of a moving stimulus at a target. Results showed that the older tennis players responded with a slight bias similar to that of the young players. Two experiments were conducted to determine whether the elimination of age effects through tennis playing was a result of maintaining basic perceptuomotor and perceptual processes or of some possible compensation strategy. The results revealed that the age-related increase in the visuomotor delay was significantly correlated with CT performance in older nonplayers but not in older tennis players. These results suggest that playing tennis is beneficial to older adults, insofar as they remained as accurate as younger ones despite less efficient perceptuomotor processes. This supports the compensation hypothesis.

Adult↗

PubMed2005

Perception-action coupling and expertise in interceptive actions.

The goal of this experiment was to show that expertise in interceptive actions can be explained by a shorter delay in movement regulation. In this contribution, we tested tennis experts and non-experts using a simulated interceptive task. The experimental device simulated linear motion of an object toward a target on a horizontal runway. Participants had to intercept the simulated moving object with their right hand holding a cart that could slide along a horizontal track perpendicular to the runway. Three different velocity conditions were used: a constant velocity condition that maintained the initial velocity (2m/s) constant until arriving on the target; the decelerated and accelerated velocity conditions, in which the velocity suddenly changed (400 ms before its arrival on the target) from 2 to 1m/s or 3m/s, respectively. Timing accuracy and movement correction after the unexpected velocity change were analysed. The experts were more accurate in the decelerative case (-29 and -124 ms respectively), in the accelerative case (69 and 116 ms respectively), but not in the constant velocity case (2 and 13 ms respectively). Findings can be explained by the shorter visuo-motor delay (VMD: the time required to adapt the movement to the new velocity) for the experts (162 ms) than for the non-experts (221 ms). This shorter VMD offers more time to adapt the interceptive movement to the new velocity. These results can be interpreted as an optimization of the perception-action coupling with expertise.

Adolescent↗

PubMed2005

Aging and tennis playing in a coincidence-timing task with an accelerating object: the role of visuomotor delay.

The purpose of the present study was to determine whether playing a specific ball sport, such as tennis, could maintain the coincidence-timing (CT) performance of older adults at a similar level to that of younger ones. To address this question, tennis players and nonplayers of three different age ranges (ages 20-30, 60-70, and 70-80 years) performed a simple CT task consisting of timing their response (pressing a button) to coincide with the arrival of a stimulus at a target. The stimulus moved at either an accelerating, constant, or decelerating velocity. As expected, all participants were affected by the velocity manipulation, which led to late and early responses to accelerating and decelerating stimuli, respectively. Whereas this response bias was increasingly pronounced with advancing age in nonplayers, no difference was found among player groups of different ages. Finally, we showed that the length of the visuomotor delay could explain the effect of nonconstant velocities.

Adult↗

PubMed2004

Age differences in estimating arrival-time.

The present study examined the accuracy in extrapolating an occluded trajectory in relation to observer age. Adults and children aged 7, 10, and 13 were tested in a prediction-motion task which consisted of judging, after the occlusion of the final part of its path, the moment of arrival of a moving stimulus towards a specified position. Results showed that children as young as 7 years old are able to use the same strategy as adults in the extrapolation of an occluded moving object. However, accuracy in responses improves most significantly for occlusion times equal to or more than 400 ms and this improvement occurs mainly between 7 and 10 years of age. This confirms that children are less efficient in performing the computations necessary to extrapolate in time an occluded trajectory.

Adolescent↗

PubMed2003

Time-to-contact estimation of accelerated stimuli is based on first-order information.

The goal of this study was to test whether 1st-order information, which does not account for acceleration, is used (a) to estimate the time to contact (TTC) of an accelerated stimulus after the occlusion of a final part of its trajectory and (b) to indirectly intercept an accelerated stimulus with a thrown projectile. Both tasks require the production of an action on the basis of predictive information acquired before the arrival of the stimulus at the target and allow the experimenter to make quantitative predictions about the participants' use (or nonuse) of 1st-order information. The results show that participants do not use information about acceleration and that they commit errors that rely quantitatively on 1st-order information even when acceleration is psychophysically detectable. In the indirect interceptive task, action is planned about 200 ms before the initiation of the movement, at which time the 1st-order TTC attains a critical value.

Adult↗