Cognitive skills and gesture-speech redundancy Formulation difficulty or communicative strategy?

Speakers sometimes convey information in their gestures that they do not convey in the accompanying speech. The present study examined whether individual differences in the production of non-redundant gesture-speech combinations are related to individual differences in speakers' spatial and verbal skills. We classified speakers as spatial dominant, verbal dominant, or equally matched on the basis of the difference in their performance on a spatial visualization test and a verbal fluency test. We used the coding procedure developed by Alibali et al. (2009) to code speakers' gesture-speech redundancy as they narrated an animated cartoon. Spatial-dominant speakers produced a higher proportion of non-redundant gesture-speech combinations than other speakers. The results suggest that some speakers may use non-redundant gesture-speech combinations as a communicative strategy that enables them to capitalize on their strong imagistic representations.