The Development of Cross-modal Perception in Tactile and Visual Domains.

Abstract

Cross-modal perception in tactile-visual modalities has been studied in the normal population. Developmental theories have suggested that cross-modal associations are naturally biased, and are stronger in children. This study aimed to test tactile-visual cross-modal interactions in adults and children and to see whether these interactions influence word naming. Forty-five adults and 39 pre-school children participated in two experiments. In experiment 1, participants either touched or looked at three pairs of 3D objects - a round vs. angular object, a soft vs. hard object and a rough vs. smooth object. For each shape, they made object-luminance associations by placing objects in a black or white box. No differences were found between whether participants touched or looked at the objects. Strong preferences were found in adults to place the round, smooth and soft objects in the white box, but contrary to predictions and developmental theories, this was not found in children. Learned experience is proposed as an explanation to support these findings. Experiment 2 was a replication of Maurer, Pathman and Mondloch’s (2006) study on the ‘bouba/kiki’ paradigm, in which children were shown two 2D shapes (one rounded and one angular) and asked which was called ‘bouba’. They found preferences to name the rounded shape ‘bouba’, and hypothesised that children were making cross-modal associations between sound and shape. We replicated Maurer et al.’s study excluding their approach of drawing attention to the experimenter’s mouth as they said the nonsense words. Contrary to Maurer et al., we found that children showed no preferences to match ‘bouba’ to the rounded shape, suggesting that Maurer et al.’s study reflected visual-visual uni-sensory mapping. This study has shown that tactile-visual cross-modality occurs in the normal population, and suggests that preferences in cross-modal associations may be stronger in adults than in children as a result of learning.