The Concurrent Programming of Saccades

Abstract

Sequences of saccades have been shown to be prepared concurrently however it remains unclear exactly what aspects of those saccades are programmed in parallel. To examine this participants were asked to make one or two target-driven saccades: a reflexive saccade; a voluntary saccade; a reflexive then a voluntary saccade; or vice versa. During the first response the position of a second target was manipulated. The new location of the second saccade target was found to impact on second saccade latencies and second saccade accuracy showing that some aspects of the second saccade program are prepared in parallel with the first. However, differences were found in the specific pattern of effects for each sequence type. These differences fit well within a general framework for saccade control in which a common priority map for saccade control is computed and the influence of saccade programs on one another depends not so much on the types of saccade being produced but rather on the rate at which their programs develop.

Face perception influences the programming of eye movements

“…Second, these error saccades were followed in the large majority of trials by a second corrective saccade bringing the gaze to the target location after a very short delay (median < 100 ms), well below the range of saccade latencies observed for the first correct and error saccades (median around 200 ms). Such extremely short inter-saccadic intervals were previously reported in studies involving the execution of two consecutive saccades and were taken as evidence that the programming of the second saccade occurred in parallel to the execution of the initial one 30,31,34,35,38,58 . At the neurobiological level, this would translate into a rise in activity of neurons in the iSC and frontal eye fields coding for the second saccade goal, while (or even before) the first saccade is being executed 36,52,59,60 .…”

Effects of task repetition but no transfer of inhibitory control training in healthy adults

“…Behavioral findings support this competitive integration account (McSorley, McCloy, & Williams, 2016;Walker & McSorley, 2006).…”

“…The neural basis of parallel saccade programming has been investigated in the context of saccadic double-step paradigms (Hu & Walker, 2011;McSorley et al, 2016;Walker & McSorley, 2006), visual search tasks (McPeek et al, 2003;McPeek & Keller, 2002;Murthy et al, 2007) and investigations on corrective saccades (Murthy et al, 2007). However, the neural basis of parallel saccade programming had not been investigated by means of neural imaging in the antisaccade paradigm, yet.…”

Top-down control of saccades requires inhibition of suddenly appearing stimuli

“…The planning hypothesis would predict that successful top-down control of eye movements depends on the time given to plan a saccade, whereas the inhibition hypothesis would state that successful oculomotor control depends on the temporal difference between stimulus onset and response and thus on how long the salient and to-beinhibited region was previewed. Because multiple saccades can be planned in parallel (McPeek, Skavenski, & Nakayama, 2000;McSorley, Gilchrist, & McCloy, 2020;McSorley, McCloy, & Williams, 2016;Quaia, Joiner, FitzGibbon, Optican, & Smith, 2010), using saccade sequences allowed us to independently manipulate the time given to saccade planning as well as the temporal onset of the vertical bar and thus the onset of the to-be-inhibited salient region. We used saccade sequences rather than a single saccade with a timed go cue, because presentation of such a go cue would have either required another visual onset or an event in another modality (e.g., auditory cue), either of which might confound saccade behavior (e.g., Vidal, Desantis, & Madelain, 2020).…”