Microsaccadic response during inhibition of return in a target–target paradigm

Abstract

This study examined the relationship between inhibition of return (IOR) in covert orienting and microsaccade statistics. Unlike a previous study [Galfano, G., Betta, E., & Turatto, M. (2004)], IOR was assessed by means of a target-target paradigm, and microsaccade dynamics were monitored as a function of both the first and the second visual event. In line with what has been reported with a cue-target paradigm, a significant directional modulation was observed opposite to the first visual event. Because participants were to respond to any stimulus, this rules out the possibility that the modulation resulted from a generic motor inhibition, showing instead that it is peculiarly coupled to the oculomotor system. Importantly, after the second visual event, a different response was observed in microsaccade orientation, whose direction critically depended of whether the second visual event appeared at the same location as the first visual event. The results are consistent with the notion that IOR is composed of both attentional and oculomotor components, and challenge the view that covert orienting paradigms engage the attentional component in isolation.

Microsaccadic modulation of response times in spatial attention tasks

“…100-300 ms), whereas with longer SOAs it is impaired, as if the target location was inhibited. IOR explanations of cue-induced eVects on microsaccade direction were reported by Betta, Galfano, and Turatto (2007) and Galfano et al (2004). There are two parallels between the current results and IOR: Wrst, the majority of cue-incongruent microsaccades (or target-congruent microsaccades following invalid cues) occurred in trials with more than a single microsaccade.…”

“…Maintenance of attention must be assumed, because it is well known that, at least with uninformative peripheral cues, inhibition of return develops over time, leading to a reduced likelihood of detecting a target at the cued location and hence to cueing costs. Inhibition of return has also been observed for microsaccades (Betta et al, 2007;Galfano et al, 2004). These attentional dynamics will likely involve saccade-preparation mechanisms.…”

Microsaccades: a neurophysiological analysis

“…By contrast, salient peripheral cues (visual or auditory, informative or uninformative) that engage exogenous attention might result in microsaccade biases opposite to the cue [72,80,83]. The observation of microsaccade biases opposite to salient and abrupt peripheral events is consistent with inhibition of return [16,75,84,85].…”

“…A related topic of ongoing debate is whether biases in microsaccade directions indicate shifts in covert attention [12,13,79] and/or motor programming [42,78,82,84].…”

Microsaccadic responses in a bimodal oddball task

“…In particular, a series of studies have been published demonstrating that the preferential direction of microsaccades is inXuenced by the orienting of spatial attention in response to central visual cues (Engbert & Kliegl, 2003;Laubrock, Engbert & Kliegl, 2005;Laubrock, Engbert, Rolfs & Kliegl, 2007; but see Horowitz, Fine, Fencsik, Yurgenson & Wolfe, 2007), peripheral visual and auditory cues (Hafed & Clark, 2002;Rolfs, Engbert & Kliegl, 2004;Galfano, Betta & Turatto, 2004;Betta, Galfano & Turatto, 2007;Rolfs, Engbert & Kliegl, 2005), and during visual search (Turatto, Valsecchi, Tamè & Betta, 2007). Furthermore, the frequency of microsaccades has also been shown to vary as a function of the preparatory state of the manual (Betta & Turatto, 2006) and ocular (Rolfs, Laubrock & Kliegl, 2006) motor systems.…”