Contextual saccadic adaptation : you can see it but you can’t learn from it

Contextual saccadic adaptation is investigated using a variant of the double-step paradigm, in which two directions of intra-saccadic steps are signaled by two different contexts. This allows to simultaneously inducing two distinct saccadic adaptations. Surprisingly, effective contextual adaptation is found when using spatially relevant cues but not when the target color and shape serve as context. Here we aim at further exploring this phenomenon to better describe the mechanisms underlying contextual motor learning. We tested eight different contextual cues to signal the intra-saccadic steps in a contextual double-step paradigm (n=80): the duration of a visual stimulus, the lateralization of a sound, various statistical regularities across trials, symbolic cues, as well as the amplitude of the first step or the target color and shape. We found robust systematic contextual learning under the amplitude condition, while no learning occurred with any of the other cues. This absence of contextual learning further confirms that predicting the intra-saccadic step strongly depends on the nature of the context. In two additional experiments replicating the previous conditions of target color and shape (n=10) and symbolic cues (n=10), participants were periodically prompted (approximately every ten trials) to explicitly report the contextual cue they had just experienced. Again, no systematic contextual adaptation was observed despite participants achieving a 91% correct report. This dissociation between perceptual reports and motor tasks involving the same visual information aligns with previous results on the constraints for contextual motor learning. It has been proposed that motor cues, as opposed to purely perceptual cues, are necessary for contextual arm or eye movement adaptation, underscoring the necessity of having contexts associated with different motor states. However, it remains unclear whether it is the planning or the execution component of the saccade that enables contextual saccade adaptation.