Despite the rapid growth of research on the crossmodal correspondence between visually presented shapes and basic tastes (e.g., sweet, sour, bitter, and salty), most studies that have been published to date have focused on shape contour (roundness/angularity). Meanwhile, other important features, such as symmetry, as well as the underlying mechanisms of the shape-taste correspondence, have rarely been studied. Over two experiments, we systematically manipulated the symmetry and contours of shapes and measured the influences of these variables on shape-taste correspondences. Furthermore, we investigated a potential underlying mechanism, based on the common affective appraisal of stimuli in different sensory modalities. We replicated the results of previous studies showing that round shapes are associated with sweet taste, whereas angular shapes are associated with sour and bitter tastes. In addition, we demonstrated a novel effect that the symmetry group of a shape influences how it is associated with taste. A significant relationship was observed between the taste and appraisal scores of the shapes, suggesting that the affective factors of pleasantness and threat underlie the shape-taste correspondence. These results were consistent across cultures, when we compared participants from Taiwanese and Western (UK, US, Canada) cultures. Our findings highlight that perceived pleasantness and threat are culturally common factors involved in at least some crossmodal correspondences.

In real-world environments, information is typically multisensory, and objects are a primary unit of information processing. Object recognition and action necessitate attentional selection of task-relevant from among task-irrelevant objects. However, the brain and cognitive mechanisms governing these processes remain not well understood. Here, we demonstrate that attentional selection of visual objects is controlled by integrated top–down audiovisual object representations (“attentional templates”) while revealing a new brain mechanism through which they can operate. In multistimulus (visual) arrays, attentional selection of objects in humans and animal models is traditionally quantified via “the N2pc component”: spatially selective enhancements of neural processing of objects within ventral visual cortices at approximately 150–300 msec poststimulus. In our adaptation of Folk et al.'s [Folk, C. L., Remington, R. W., & Johnston, J. C. Involuntary covert orienting is contingent on attentional control settings. Journal of Experimental Psychology: Human Perception and Performance, 18, 1030–1044, 1992] spatial cueing paradigm, visual cues elicited weaker behavioral attention capture and an attenuated N2pc during audiovisual versus visual search. To provide direct evidence for the brain, and so, cognitive, mechanisms underlying top–down control in multisensory search, we analyzed global features of the electrical field at the scalp across our N2pcs. In the N2pc time window (170–270 msec), color cues elicited brain responses differing in strength and their topography. This latter finding is indicative of changes in active brain sources. Thus, in multisensory environments, attentional selection is controlled via integrated top–down object representations, and so not only by separate sensory-specific top–down feature templates (as suggested by traditional N2pc analyses). We discuss how the electrical neuroimaging approach can aid research on top–down attentional control in naturalistic, multisensory settings and on other neurocognitive functions in the growing area of real-world neuroscience.

AbstractAttentional control outside of the laboratory operates in multisensory settings, but the development of mechanisms subserving such control remains poorly understood. We investigated when, over the course of childhood, adult-like attentional control mechanisms begin to emerge. Children aged five, seven, and nine were compared with adults on behavioural performance in a computer game-like multisensory spatial cueing task, while simultaneous 129-channel EEG was recorded. Markers of attentional control were behavioural spatial cueing effects and the N2pc ERP component (analysed both traditionally and using a novel, multivariate electrical neuroimaging framework). In behaviour, adult-like visual attentional control was present from age 7 onwards, whereas multisensory control was not seen in children. In EEG, multivariate analyses of the activity over the N2pc time-window, revealed stable patterns of brain activity in children. Adult activity patterns linked to visual attentional control were present age 7 onwards, mirroring behaviour. Activity patterns linked to multisensory control were found in 9-year-olds, even though such patterns were not noted in behaviour. By combining rigorous yet naturalistic paradigms with multivariate signal analyses, we provided new insights into the development of visual attentional control skills vis-à-vis multisensory attentional control, thus generating a more complete account of attentional development.HighlightsBehaviourally, visual attentional control, as measured by task-set contingent attentional capture, was found to reach an adult-like state as early as age 7Behaviourally, attentional enhancement from multisensory stimuli was not found in 9-year-olds, but their EEG topographic patterns were different for multisensory vs. purely visual distractorsTraditional visual attentional event-related analyses, such as the N2pc, are not sensitive to detect attentional enhancement for multisensory objects in adults, and visual or multisensory attention in childrenSensitive, multivariate analyses of the event-related potential signal, such as electrical neuroimaging, are adept at revealing the neural underpinnings of attentional control processes over development