Cross-sensory correspondences:cross-activation of connotative feature dimensions through the felt heaviness of lifted objects

Cross-sensory correspondences are the systematic associations demonstrated to arise between various feature dimensions such that their relative extremes are aligned. It has been proposed that correspondences arise as a result of cross-talk between abstract, amodal connotations of a core set of feature dimensions (P. Walker, 2016). Although there is some evidence to suggest that a dimension denoting heaviness may be included among a set of aligned feature dimension, the evidence to demonstrate this is limited. The present work explores whether heaviness, as received through the lifting of weighted objects, may enter into this scheme of correspondences. In addition, the separate contributions of the heaviness and size of lifted objects to the cross-activation of other feature dimensions is also considered. The influences of size and heaviness were explored in light of the size-weight illusion; a phenomenon where the size of equally weighted objects alters their felt heaviness such that the smaller object is experienced to be heavier than the larger object. A series of rating scale tasks were conducted, examining whether heaviness can induce predicted correspondences with other feature dimensions. It was demonstrated that heavier objects were consistently aligned with dark and low pitch. Further confirmation for these mappings was sought through a series of speeded classification tasks. The heaviness-brightness mapping was demonstrated to influence response speed in a brightness classification task, where objects varying in heaviness were used as response keys. In both rating scale and speeded classification tasks, the heaviness-brightness correspondence continued to form the basis of cross-sensory interactions despite the potential for a size-brightness correspondence. The present work confirms that cross-activation between dimensions can be accessed through the manipulation of felt objects. What is more, support is provided for a framework of aligned feature dimensions, their conceptual nature and the inclusion of heaviness among this proposed network of dimensions

Cross-sensory correspondences:heaviness is dark and low-pitched

Everyday language reveals how stimuli encoded in one sensory feature domain can possess qualities normally associated with a different domain (e.g., higher pitch sounds are bright, light in weight, sharp, and thin). Such cross-sensory associations appear to reflect crosstalk among aligned (corresponding) feature dimensions, including brightness, heaviness, and sharpness. Evidence for heaviness being one such dimension is very limited, with heaviness appearing primarily as a verbal associate of other feature contrasts (e.g., darker objects and lower pitch sounds are heavier than their opposites). Given the presumed bi-directionality of the crosstalk between corresponding dimensions, heaviness should itself induce the cross-sensory associations observed elsewhere, including with brightness and pitch. Taking care to dissociate effects arising from the size and mass of an object this is confirmed. When hidden objects varying independently in size and mass are lifted, objects that feel heavier are judged to be darker and to make lower pitch sounds than objects feeling less heavy. These judgements track the changes in perceived heaviness induced by the size-weight illusion. The potential involvement of language, natural scene statistics, and Bayesian processes in correspondences, and the effects they induce, is considered

Heaviness-brightness correspondence and stimulus-response compatibility

Cross-sensory correspondences can reflect crosstalk between aligned conceptual feature dimensions, though uncertainty remains regarding the identities of all the dimensions involved. It is unclear, for example, if heaviness contributes to correspondences separately from size. Taking steps to dissociate variations in heaviness from variations in size, the question was asked if a heaviness-brightness correspondence will induce a congruity effect during the speeded brightness classification of simple visual stimuli. Participants classified the stimuli according to whether they were brighter or darker than the mid-gray background against which they appeared. They registered their speeded decisions by manipulating (e.g., tapping) the object they were holding in either their left or right hand (e.g., left for bright, right for dark). With these two otherwise identical objects contrasting in their weight, stimuli were classified more quickly when the relative heaviness of the object needing to be manipulated corresponded with the brightness of the stimulus being classified (e.g., the heavier object for a darker stimulus). This novel congruity effect, in the guise of a stimulus-response (S-R) compatibility effect, was induced when heaviness was isolated as an enduring feature of the object needing to be manipulated. It was also undiminished when participants completed a concurrent verbal memory load task, countering claims that the heaviness-brightness correspondence is verbally mediated. Heaviness, alongside size, appears to contribute to cross-sensory correspondences in its own right and in a manner confirming the far-reaching influence of corre- spondences, extending here to the fluency with which people communicate simple ideas by manipulating a hand-held object