A Simon effect for threat-related stimulus content.

When a threat-related stimulus is preferentially processed, it may act as if it is presented alone, and thus trigger processes comparable with the effects elicited by a single stimulus. Peripheral stimuli are known to yield a Simon effect: faster responses when stimulus and response spatially correspond than when not. We designed a task during which a threat-related (physical threat, social threat, or height) word is presented with a neutral word (14 or 500 ms, masked), one above the other, and spatial correspondence of threat-related word and response varies across trials. Undergraduates performed this task when exposed to height (N=22) or in a lab (N=25). The height group, compared to the control group, showed a content-specific Simon effect for physical-threat words. This result adds evidence to the hypothesis of preferential processing of relevant threat-related information.