Abstract
In a spatial negative priming (SNP) paradigm, when a previously ignored location subsequently contains the target to be selected, responses to it are impaired, resulting in increased response times. Previous studies have measured SNP using simple button presses. In the present experiment, we asked whether the oculomotor system would exhibit a similar pattern of results: increased latencies to shift the gaze toward a location that previously contained a stimulus but was ignored (not fixated). Participants were presented with a cross-shaped grid containing four possible locations in which a stimulus could appear as we recorded eye movements with a corneal reflection eye tracker. Two conditions were presented randomly, ignored repetition and control, for a total of 48 trials. Each trial consisted of two parts, a prime and a probe, each lasting 2000 ms. In the prime trials, the target (an animated moving toy with accompanying sound) in one location was accompanied by a distractor (gray diamond) in another location. In ignored repetition probe trials, a target appeared next in the location that the distractor had previously occupied. Control trials were identical except that the probe target appeared in a different location than the distractor. The task was simply to fixate the target and ignore the distractor. We found that saccade latencies to the target were faster on control trials than on ignored repetition trials, (M=245.11ms, SD=37.97 for ignored repetition condition, M=187.9 ms, SD=23.46 for control condition; p < .05). These results suggest that selective attention mechanisms can be measured at the level of eye movements, and that the SNP effect may generalize across response domains.