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Philippe Boulinguez

Publications and source records attributed to Philippe Boulinguez.

4 recordsLinked to original sources
PubMed2003

Hemispheric asymmetry for trajectory perception.

Broadly, the right hemisphere is known to be specialized for spatial processing whereas the left hemisphere is known to be specialized for temporal processing. However, it remains unclear how both hemispheres interact when processing spatio-temporal information. This study investigates, from a behavioral point of view, whether spatio-temporal processing involved in trajectory perception generates hemispheric asymmetries. An experimental task requiring the prediction of coincidence between ballistic trajectories and a stationary target was used. Reaction times were analyzed according to various interhemispheric conditions determined by the visual hemifield on which the stimulus was presented and the hand of response. There was shorter reaction time for the left hand than the right hand, and shorter reaction times for the left visual hemifield than the right visual hemifield for both hands. From these findings, it is inferred that there is likely to be right hemisphere specialization for trajectory perception and that this hemispheric asymmetry is independent of handedness.

Adult↗
PubMed2002

Manual asymmetries in the directional coding of reaching: further evidence for hemispatial effects and right hemisphere dominance for movement planning.

Directional coding of hand movements is of primary importance in the proactive control of goal-directed aiming. At the same time, manual reaction times are known to be asymmetric when reaching at lateralized targets. Generally, ipsilateral movements and left hand advantages are interpreted using the classical model of interhemispheric transmission for simple visuomotor integration, but the use of this model was recently challenged when applied to reaching movements, arguing that attentional and biomechanical effects could also account for such asymmetries. In this work, we aimed at controlling both visual attention orienting and movement mechanical constraints in order to clarify the origin of manual reaction time asymmetries and hemispatial effects in the directional coding of reaching. Choice reaction time pointing tasks were assessed in two experiments in which identical movements were compared in different conditions of target lateralization and different conditions of head, eye and hand position. Results suggested that biomechanical constraints could account for hemispatial effects for movement execution but not for movement direction coding. These results are discussed in the light of models of interhemispheric cooperation and the right hemisphere dominance for spatial processing.

Adult↗
PubMed2002

Orienting visuospatial attention generates manual reaction time asymmetries in target detection and pointing.

Right-handers exhibit a left hand advantage in response preparation when pointing to targets. These manual asymmetries are generally attributed to a right hemisphere specialization for spatial processing. More precisely, the left hand reaction time (RT) advantage was recently supposed to reflect specifically the right hemisphere superiority for movement planning. This study proposes to investigate a possible attentional origin for manual RT asymmetries. In a first experiment, we used the covert orienting of attention paradigm to measure subjects' RTs when reaching at targets (pointing task) both in valid, neutral and invalid conditions, either in the left or in the right visual fields and with the left and the right hand. In a second experiment, we applied the same paradigm to a detection task (key-pressing). Results revealed that orienting of attention to spatial locations was more time consuming when responding with the right than with the left hand, whether movement planning was required or not. It is suggested that the right hemisphere dominance for orienting of visuospatial attention account, partly at least, for the RT asymmetries classically observed in manual aiming.

Adolescent↗