Asymmetrical after-effects of prism adaptation during goal oriented locomotion.
In healthy subjects, sensorimotor after-effects of prism adaptation are known to be symmetric (they appear after using leftward and rightward optical deviations), whereas cognitive after-effects are asymmetric (they appear after using a leftward optical deviation) and rightward oriented. Sensorimotor and cognitive after-effects have been classically studied using different specific tasks. The purpose of the current study was to investigate whether both after-effects may be involved in a same visuo-spatial task. Therefore we compared the amplitude of after-effects following adaptation to a rightward or leftward optical deviation. After-effects were assessed by manual pointing or goal oriented locomotor task. The main result showed a greater amplitude for rightward locomotor after-effects (after adaptation to a leftward deviation) than for leftward locomotor after-effects (after adaptation to a rightward deviation). This means that cognitive after-effects may add to sensorimotor after-effects following adaptation to a leftward optical deviation. This asymmetry challenges the classical distinction between sensorimotor and cognitive after-effects of prism adaptation. Implications for the functional mechanisms and the neuroanatomical substrate of prism adaptation are discussed.
Michel
Carine
C
UFR STAPS, Université de Bourgogne, Dijon, Campus Universitaire, BP 27877, 21078 Dijon, France. Carine.Michel@u-bourgogne.fr
Vernet
Paul
P
Courtine
Grégoire
G
Ballay
Yves
Y
Pozzo
Thierry
T
D000222:Adaptation, Physiological / Q000502:physiology*; D000328:Adult; D007839:Functional Laterality / Q000502:physiology*; D006040:Goals; D006801:Humans; D009043:Motor Activity / Q000502:physiology*; D009949:Orientation / Q000502:physiology; D010775:Photic Stimulation / Q000379:methods*; D011597:Psychomotor Performance / Q000502:physiology*; D013028:Space Perception / Q000502:physiology; D014796:Visual Perception / Q000502:physiology