Abstract
Attentional filters ensure that relevant information is processed and irrelevant information is filtered out. It is well known that a distractor appearing outside the focus of attention disrupts spatial attention, but what are the consequences for non-spatial attentional filters? In two fMRI experiments, participants attended different object categories while viewing hybrid image arrays (superimposed face/house [E1] or face/house/shoe [E2] pairs). On distractor-absent trials, we observed the standard signature of category-tuned attentional filtering: greater FFA activation when attending faces, PPA when attending scenes, and LOC when attending shoes. When a salient distractor appeared, however, category-tuned filtering was dramatically disrupted. Strikingly, the neural filters were not simply reset, but briefly inverted, such that to-be-ignored categories were incidentally prioritized. To further quantify attentional facilitation and suppression, in E2, single-category image conditions (faces only, houses only, shoes only) were also included as benchmarks. On distractor-absent trials, activation in FFA when attending faces in hybrids was comparable to viewing faces-only, and activation when ignoring-faces in hybrids was comparable to faces-absent; the same was true for the other ROIs, suggesting effective facilitation of the target category and suppression of the nontarget category. Interestingly, on distractor-present trials, facilitation and suppression were both disrupted. Thus, when there is attentional competition (hybrid images), spatial distraction can be so disruptive as to actually invert these filters; processing of the task-relevant object category is reduced, while processing of the task-irrelevant category is boosted. Extending the Filter Disruption Theory (Dube & Golomb, 2022), the current results reveal that in addition to disrupting spatial attention, distraction disrupts category-tuned attentional filters, via temporary disruptions to mechanisms of both facilitation and suppression.