Poster Session D, Monday, March 25, 8:00 – 10:00 am, Pacific Concourse
Does sound-shape correspondence modulate a neuronal signature of visual shape processing for attended shapes?
Erinda Morina1, Hiu Mei Chow2, Vivian M. Ciaramitaro1; 1University of Massachusetts Boston, 2University of British Columbia
Crossmodal correspondences highlight naturally occurring associations across our senses. In the bouba/kiki effect, abstract shapes are associated with unrelated nonsense words, such that round shapes are matched to /bouba/ sounds and spiky shapes to /kiki/ sounds. Such associations have been found across cultures, languages, and across development. We used steady state evoked potentials (SSEPs) to examine how neural responses to a given visual feature depend on the auditory feature naturally associated with the visual feature. We hypothesized that neuronal responses to the same attended shape (e.g. spiky) would be enhanced for congruent (e.g. /ki/) vs incongruent (e.g. /ba/) sounds. Twenty-four subjects viewed one round and one spikey shape, each half-shape presented in a given visual hemifield. Visual shapes flickered at different frequencies (5.45, 7.5Hz) and were presented under one of three auditory conditions: no sound, /ba/ sound or /ki/ sound (3 Hz). Participants attended fixation to detect a color change, attended a given visual shape to detect a shape border thickening, or attended the auditory sound to detect a volume change. Signal-to-noise ratios were measured at the fundamental frequencies of visual stimulus presentation to quantify the strength of neural processing of visual shapes under different attention and crossmodal conditions. We found enhanced neuronal responses for a given attended shape when the unattended sound was congruent vs incongruent, but no difference in neural responses based on sound congruence when attention was directed to fixation and visual shapes were unattended, suggesting an influence of endogenous feature-based attention on crossmodal correspondence.
Topic Area: ATTENTION: Multisensory