Abstract
Synaesthesia is a fascinating condition whereby individuals report extraordinary experiences when presented with ordinary stimuli. Here we examined an individual (EM) who experiences time units (i.e., months of the year and hours of the day) as occupying specific spatial locations (January is 30° to the left of midline). This time-space synaesthesia has been recently investigated by Smilek, Callejas, Dixon, and Merikle (2007) who demonstrated that the time-space associations are highly consistent, occur regardless of intention, and can direct spatial attention. We extended this work by showing that for EM, her time-space associations change depending on whether the time units are seen or heard. For example, when EM sees the word JANUARY, she reports experiencing January on her left side, however when she hears the word “January” then this month is synaesthetically experienced on her right side. EM's subjective reports were supported using a spatial cueing paradigm. The names of months were centrally presented followed by targets on the left or right. EM was faster at detecting targets in validly cued relative to invalidly cued locations both for visually presented cues (January orients attention to the left) and for aurally presented cues (January orients attention to the right). We replicated these different visual and aural cueing effects using hours of day. Our findings support previous research showing that time-space synaesthesia can bias visual spatial attention, and further suggest that for some synaesthetes, time-space associations can differ depending on whether they are visually or aurally induced.
This research was supported by the Natural Sciences and Engineering Research Council of Canada (NSERC) with a grant to M.D. and a graduate scholarship to M.J.