Beyond race model predictions: The temporal dynamics of multisensory attentional capture

Attentional resources are crucial in determining whether and how a specific stimulus is selected for further processing from a multitude of concurrent inputs. Within this framework, multisensory integration enhances the salience of environmental stimuli amplifying perceptual responses to events. According to the race model, competition among sensory modalities in multisensory stimulation resembles a race; thus, when bimodal or trimodal stimulation elicits faster responses compared to unimodal stimulation, the model's prediction is violated. The present study aimed to validate a technological device capable of delivering unimodal, bimodal and trimodal stimulation, and to investigate perceptual processes and attentional dynamics by applying the race model to multisensory data, utilizing a previous multisensory attentional paradigm. Our findings provide compelling evidence of facilitatory attentional capture by multisensory events, as reflected in faster detection times compared to unisensory stimuli. Notably, this advantage is most pronounced in the initial segment of the cumulative distribution function, where responses are less influenced by higher cognitive mechanisms. Additionally, manipulation of perceptual load created an interfering effect in preliminary analyses, not found within the race model. The Tech-PAD proves to be a valuable tool for replicating and expanding research paradigms. The results reinforce previous findings and extend the multisensory advantage to the trimodal condition, including the tactile modality. Furthermore, this study highlights the role of attentional control mechanisms in multisensory environments, particularly in the early stages of sensory perception. The findings are interpreted in relation to attentional mechanisms and cognitively efficient strategies, offering new insights into the optimization of sensory processing.