Background: One cognitive feature of schizophrenia (SZ) is a deficit in the ability to disengage attention from salient events in peripheral vision (Maruff et al., 1998). We investigated whether an analogous attention deficit might occur in SZ in the auditory sensory modality; i.e., whether individuals with SZ may experience a difficulty shifting attention away from the location of a sound. Methods: We used a technique similar to Posner's (1980) spatial cueing paradigm, but with peripheral auditory cues and visual targets. The target could be presented either same side or contralateral to the spatial location from which the cue had sounded 200 ms prior, and participants executed a saccadic eye movement to the target. Three conditions varied the probability of the target appearing on the same side as the cue (20%, 50%, and 80% target-at-cue conditions). Saccadic latencies were subjected to an ANOVA with 2 repeated measures factors (Congruency and Condition), and with Group (SZ vs. Controls) as a between-groups measure.
Results: The ANOVA revealed a sig. Congruency effect (i.e., latency advantage for visual targets same side vs. opposite side to the auditory cue), F = 108.9, p < .001, and a sig. Congruency x Condition interaction, F = 18.31, p < .001; post hoc contrasts revealed a greater Congruency effect in the 80% target-at-cue condition. The only significant interaction involving Group was Group x Congruency, F = 9.94, p < .005, indicating a larger Congruency effect for SZ.
Discussion: In both healthy individuals and patients with SZ, visual attention is reflexively drawn to the spatial location of an auditory stimulus, even if the target visual event is unlikely to occur at that location. The magnitude of this effect is larger in SZ, however, suggesting that, on congruent trials the visual attention of individuals with SZ is more readily captured by an auditory stimulus, and they may also be slower to disengage attention from an auditory signal.