ERP evidence of attentional selection outside of effective oculomotor range
摘要
The close link between visual attention and the oculomotor system is well documented. Within the selection-for-action framework, two perspectives exist. According to Visual Attention Model (VAM) attention is seen as a prerequisite for successful movement execution, though it is considered a distinct cognitive and neural process. By contrast, the premotor theory of attention (PMTA) argues that the beneficial effects of attention are fully accounted for by the system’s preparation for saccadic eye movements. From this standpoint, a central prediction emerges: attentional advantages should be confined to regions within the oculomotor range, since saccadic planning is not feasible outside those limits. A common way to examine this prediction is to present cues and targets in a hemifield beyond the oculomotor range, typically achieved by occluding one eye while abducting the other. Using this method, Smith et al. showed that in a visual search task, exogenous orienting is reduced in the temporal hemifield when the eye is abducted. They concluded that exogenous attentional orienting is constrained by the range of potential saccadic movements. In our study, we sought to replicate Smith et al.’s findings while extending the paradigm with EEG recordings—an approach not yet applied in this context. PMTA predicts that, under eye abduction, stimuli appearing in the temporal hemifield would yield diminished N2pc amplitudes. An ANOVA revealed no reduction of N2pc amplitude in the temporal hemifield. Taken together, our results support the growing body of evidence suggesting that visual attention is not strictly bound to the oculomotor range.