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Contemporary schemas of brain organization now include multisensory processes both in low-level cortices as well as at early stages of stimulus processing. Evidence has also accumulated showing that unisensory stimulus processing can result in cross-modal effects. For example, task-irrelevant and lateralised sounds can activate visual cortices; a phenomenon referred to as the auditory-evoked contralateral occipital positivity (ACOP). Some claim this is an example of automatic attentional capture in visual cortices. Other results, however, indicate that context may play a determinant role. Here, we investigated whether selective attention to spatial features of sounds is a determining factor in eliciting the ACOP. We recorded high-density auditory evoked potentials (AEPs) while participants selectively attended and discriminated sounds according to four possible stimulus attributes: location, pitch, speaker identity or syllable. Sound acoustics were held constant, and their location was always equiprobable (50% left, 50% right). The only manipulation was to which sound dimension participants attended. We analysed the AEP data from healthy participants within an electrical neuroimaging framework. The presence of sound-elicited activations of visual cortices depended on the to-be-discriminated, goal-based dimension. The ACOP was elicited only when participants were required to discriminate sound location, but not when they attended to any of the non-spatial features. These results provide a further indication that the ACOP is not automatic. Moreover, our findings showcase the interplay between task-relevance and spatial (un)predictability in determining the presence of the cross-modal activation of visual cortices., Competing Interests: Declaration of competing interest Authors report no conflict of interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Real-world environments are nearly always multisensory in nature. Processing in such situations confers perceptual advantages, but its automaticity remains poorly understood. Automaticity has been invoked to explain the activation of visual cortices by laterally-presented sounds. This has been observed even when the sounds were task-irrelevant and spatially uninformative about subsequent targets. An auditory-evoked contralateral occipital positivity (ACOP) at ~250ms post-sound onset has been postulated as the event-related potential (ERP) correlate of this cross-modal effect. However, the spatial dimension of the stimuli was nevertheless relevant in virtually all prior studies where the ACOP was observed. By manipulating the implicit predictability of the location of lateralised sounds in a passive auditory paradigm, we tested the automaticity of cross-modal activations of visual cortices. 128-channel ERP data from healthy participants were analysed within an electrical neuroimaging framework. The timing, topography, and localisation resembled previous characterisations of the ACOP. However, the cross-modal activations of visual cortices by sounds were critically dependent on whether the sound location was (un)predictable. Our results are the first direct evidence that this particular cross-modal process is not (fully) automatic; instead, it is context-contingent. More generally, the present findings provide novel insights into the importance of context-related factors in controlling information processing across the senses, and call for a revision of current models of automaticity in cognitive sciences., (Copyright © 2015 Elsevier Inc. All rights reserved.)