Modality-specific interaction between phonology and semantics Gail Moroschan & Chris Westbury Department of Psychology, University of Alberta, Edmonton, Alberta, Canada Introduction: Previous psycholinguistic studies have suggested that semantics feeds back to phonology during lexical access. The results of an fMRI study done by Binder, Westbury, Possing, and McKiernan (2003) suggest that word imageability could also play a role as abstract words and concrete words activate different areas involved in phonological and semantic processing (Figure 1). The two experiments presented here are a continuation of a group of experiments conducted by Westbury and Binder (2003) to show behavioral evidence of this interaction effect. Method: In the following two experiments, subjects had to make a semantic decision based on imageability. Both experiments looked at reaction times (RT) and used the manipulation of phonological neighborhood (PN) as well as imageability (concrete vs. abstract). The stimuli was presented using two modalities: auditory presentation, and visual presentation using pseudohomophones. Pseudohomophones are non-words that sound like real words when pronounced. The use of pseudohomophones in the visual experiment was necessary to rule out orthographic effects. Subjects were asked to decide if the stimuli presented to them sounded like a concrete word (that is, something you can see, touch, hold in your hand, etc) and respond ‘yes’ or ‘no’. We excluded RT’s below 300 ms or above 3500 ms, and only used RT’s for correct decisions. Auditory Concreteness Decision Experiment (Figure 2) 30 subjects (6 male, 24 female) listened to 82 words presented auditorily through headphones. Results: A main effect of imageability was found (p<0.01), but no effects of PN (p=0.1). However, a significant interaction effect was seen between PN and imageability (p<0.01) when auditory presentation was used. Figure 1: Abstract and Concrete word activation. Abstract words (blue) activated areas in the frontal and temporal lobes associated with phonological processing. Concrete words (orange) showed activations in sensory association areas. Visual Pseudohomophone Concreteness Decision Experiment (Figure 3) 30 subjects (9 male, 21 female) saw a visual presentation of 100 pseudohomophones on an iMac monitor. Results: Again, a main effect of imageability was found (p<0.01). However, no effects of PN or interaction effects between PN and imageability were found when visual presentation was used. Discussion and Conclusion: We were successful in showing an interaction effect between phonology and imageability for words presented auditorily but not for those presented visually. This interaction effect does provide further support that semantics feeds back to phonology during lexical access, especially when phonology is emphasized over orthography by using auditory presentation. References: Binder,J.R., Westbury, C.F., Possing, E.T., McKiernan, K.A.(2003). Neural correlates of concrete and abstract word recognition. Poster presentation at the Annual Meeting of the Society for Cognitive Neuroscience, New York, NY. Binder,J.R., Westbury, C.F., Possing, E.T., McKiernan, K.A.(2003). Neural correlates of concrete and abstract word recognition. Poster presentation at the Annual Meeting of the Society for Cognitive Neuroscience, New York, NY. Westbury, C.F., Binder, J.R.(November, 2003). Abstracting meaning from sound: Interactions between concreteness and phonology. Poster presentation at Psychonomics Society Annual Meeting, Vancouver, BC. Westbury, C.F., Binder, J.R.(November, 2003). Abstracting meaning from sound: Interactions between concreteness and phonology. Poster presentation at Psychonomics Society Annual Meeting, Vancouver, BC. * Figure 2: A significant interaction effect was found when using the auditory modality. Figure 3: No significant interaction effects were found when using the visual modality. L R