Irrelevant auditory and tactile signals, but not visual signals, interact with the target onset and modulate saccade latencies

Abstract

Saccadic eye movements bring events of interest to the center of the retina, enabling 11 detailed visual analysis. This study explored whether irrelevant auditory (experiments A, B & F), visual 12 (C & D) or tactile signals (E & F) delivered around the onset of a visual target modulates saccade 13 latency. Participants were instructed to execute a quick saccade toward a target stepping left or right 14 from a fixation position. We observed an interaction between auditory beeps or tactile vibrations 15 and the oculomotor reaction that included two components: a warning effect resulting in faster 16 saccades when the signal and the target were presented simultaneously; and a modulation effect 17 with shorter -or longer -latencies when auditory and tactile signals were delivered before -or after 18 -the target onset. Combining both modalities only increased the modulation effect to a limited 19extent, pointing to a saturation of the multisensory interaction with the motor control. Interestingly, 20 irrelevant visual stimuli (black background or isoluminant noise stripes in peripheral vision, flashed 21 for 10 ms) increased saccade latency whether they were presented just before or after target onset. 22 The lack of latency reduction with visual signals suggests that the modulation observed in the 23 auditory and tactile experiments was not related to priming effects but rather to low-level audio-and 24 tactile-visual integration. The increase in saccade latency observed with irrelevant visual stimuli is 25 discussed in relation to saccadic inhibition. Our results demonstrate that signals conveying no 26 information regarding where and when a visual target would appear modulate saccadic reactivity, 27 much like in multisensory temporal binding, but only when these signals come from a different 28 modality. 29

Cross-modal perceptual enhancement of unisensory targets is uni-directional and does not affect temporal expectations

“…However, multisensory interactions are typically reported to enhance performance (Alais & Burr, 2004; Driver & Noesselt, 2008; Gondan et al, 2005; McDonald et al, 2000; Noesselt et al, 2007, 2010; Parise et al, 2012; Starke et al, 2020; Teder-Sälejärvi et al, 2005; Werner & Noppeney, 2010) which was only the case for the visual but not the auditory target in multisensory sequences. Thus, our results extend the literature of improvements of visual performance by irrelevant sounds (Maddox et al, 2015; Noesselt et al, 2010; Stein et al, 1996; Van der Burg et al, 2008; Van Vleet & Robertson, 2006; Vidal et al, 2020; Vroomen & De Gelder, 2000) by showing that such enhancement can also be achieved by asynchronously presented sounds embedded in fast stimulus sequences and when participants are oblivious about target’s modality (i.e. the multisensory sequence type was non-predictive of target’s modality).…”

“…To start with, a plethora of studies showed that an irrelevant stimulus can affect perception and reactions to a relevant target stimulus of a different modality (Lovelace et al, 2003; Maddox et al, 2015; Noesselt et al, 2010; Starke et al, 2020; Stein et al, 1996; Thorne & Debener, 2008; Van der Burg et al, 2008; Van Vleet & Robertson, 2006; Vidal et al, 2020; Vroomen & De Gelder, 2000). For instance, presenting an irrelevant auditory stimulus in combination with a visual target can result in increased perceived brightness of the visual target stimulus (Noesselt et al, 2008; Stein et al, 1996).…”

“…While most previous studies focussed on the influence of the auditory on the visual modality there is also partial evidence that the visual modality can affect perception of relevant auditory targets (Lovelace et al, 2003; Starke et al, 2020; Thorne & Debener, 2008). For instance, Starke et al (2020) showed that an uninformative and irrelevant visual stimulus improves performance in an auditory tasks (though see Vidal et al, 2020). Irrespective of the direction of cross-modal influences, all the effects mentioned above might be linked to activity changes of bimodal neurons which often exhibit supramodal superadditive activity (Meredith & Stein, 1986; Noesselt et al, 2010; Stevenson et al, 2007; Stevenson & James, 2009; Werner & Noppeney, 2010) but can also exhibit subadditive activity (Angelaki et al, 2009).…”