Expected but omitted stimuli affect crossmodal interaction

Abstract

One of the most important ability of our brain is to integrate input from different sensory modalities to create a coherent representation of the environment. Does expectation affect such multisensory integration? In this paper, we tackled this issue by taking advantage from the crossmodal congruency effect (CCE). Participants made elevation judgments to visual target while ignoring tactile distractors. We manipulated the expectation of the tactile distractor by pairing the tactile stimulus to the index finger with a high-frequency tone and the tactile stimulus to the thumb with a low-frequency tone in 80% of the trials. In the remaining trials we delivered the tone and the visual target, but the tactile distractor was omitted (Study 1). Results fully replicated the basic crossmodal congruency effect. Strikingly, the CCE was observed, though at a lesser degree, also when the tactile distractor was not presented but merely expected. The contingencies between tones and tactile distractors were reversed in a follow-up study (Study 2), and the effect was further tested in two conceptual replications using different combinations of stimuli (Studies 5 and 6). Two control studies ruled out alternative explanations of the observed effect that would not involve a role for tactile distractors (Studies 3, 4). Two additional control studies unequivocally proved the dependency of the CCE on the spatial and temporal expectation of the distractors (Study 7, 8). An internal small-scale meta-analysis showed that the crossmodal congruency effect with predicted distractors is a robust medium size effect. Our findings reveal that multisensory integration, one of the most basic and ubiquitous mechanisms to encode external events, benefits from expectation of sensory input.

Implicit expectation modulates multisensory perception

“…Finally, the association is entirely arbitrary and not driven by an underlying spatiotemporal effect, semantic association, or crossmodal correspondence. This supports previous research suggesting that expectations create predictions about forthcoming sensory events, providing a key mechanism to cope with sensory ambiguity (Costantini et al, 2018 ).…”

“…This is a distinction that previous research has not typically made. For example, Gekas et al ( 2015 ) and Van Wanrooij et al ( 2010 ) examined expectation in visual search and audio-visual orienting paradigms respectively, and Costantini et al ( 2018 ) found a visuo-tactile cross congruency effect even when a tactile distractor was expected but omitted. While each of these studies show an effect of expectation on perceptual processes, the expectation itself is purely stimulus driven.…”

Heart is deceitful above all things: Threat expectancy induces the illusory perception of increased heartrate

“…Nevertheless, a growing body of evidence suggests that top-down influences in the tasks used here do not just reflect heartbeat beliefs themselves, but their integration into cardiac perception (Körmendi et al, 2021(Körmendi et al, , 2022Ring & Brener, 2018), as proposed by the predictive coding frameworks our work is based on (Barrett & Simmons, 2015;Costantini, 2014;Costantini et al, 2018;Critchley & Garfinkel, 2017;Ferri et al, 2013). Here, several aspects of the present data similarly point to the predicted integration of higher-order beliefs with the cardiac perception itself, rather than an influence of the heartrate beliefs themselves.…”