Disconjugate memory-guided saccades to disparate targets: evidence for 3D sensitivity.
The saccadic system has been traditionally regarded as two-dimensional (horizontal, vertical) and basically conjugate in the two eyes. However, saccades to disparate targets (e.g., targets in real three-dimensional space that are located in different directions and at different distances) are naturally disconjugate. We report here that memory-guided saccades to a disparate target flashed 1 s earlier become disconjugate following repeated trials. After 15 min of repetition, the disconjugacy persists even when the target to be remembered is no longer disparate. This suggests fast memory-based learning. Learning, however, fails to occur if, during the repetition trials, the memory delay is 2 s. These findings suggest that the saccadic system has access to a 3D representation of targets and is gifted with 3D short-term memory and learning capacity.
Kapoula
Z
Z
Laboratoire de Physiologie de la Perception et de l'Action, UMR 9950, CNRS-Collège de France, Paris, France. zk@ccr.jussieu.fr
Bucci
M P
MP
Lavigne-Tomps
F
F
Zamfirescu
F
F
D000221:Adaptation, Ocular / Q000502:physiology*; D000839:Aniseikonia / Q000503:physiopathology*; D001245:Association Learning / Q000502:physiology; D006801:Humans; D008570:Memory, Short-Term / Q000502:physiology*; D012016:Reference Values; D012438:Saccades / Q000502:physiology*; D013028:Space Perception / Q000502:physiology*; D015348:Vision, Binocular / Q000502:physiology*