Examining the Feature-Based Filtering Hypothesis of the Attentional Boost Effect

Prior study suggests that the attentional boost effect (ABE) operates at the object level and is modulated by feature-based filtering (Joe et al., 2026). The present study aims to examine the feature-based filtering out hypothesis. If the feature-based filtering out is the core mechanism for ABE, background images presented with distractors containing target features but misbound would show memory enhancement. This research project investigates the mechanisms underlying the attentional boost effect (ABE), with a particular focus on the role of feature-based filtering in modulating memory enhancement. The attentional boost effect refers to the phenomenon in which the detection of behaviorally relevant targets during a task transiently enhances the encoding of concurrently presented information. Joe et al. (2026) suggest that the ABE operates at the object level and may be influenced by feature-based filtering. However, the precise role of feature-based filtering in producing the attentional boost remains unclear. The present study aims to directly test the feature-based filtering-out hypothesis as a potential core mechanism underlying the ABE. This hypothesis proposes that attentional enhancement during target detection is not restricted to correctly bound target objects but can also be triggered by stimuli that share relevant features with the target, even when those features are incorrectly bound to other object attributes. In other words, if the ABE operates primarily at the level of features rather than fully integrated objects, stimuli containing target-defining features—even when those features are incorrectly bound—may still produce memory benefits for background images presented concurrently with those stimuli. The present study examines whether background images presented concurrently with distractor stimuli containing misbound target features show enhanced subsequent memory. In the experimental paradigm, participants perform a detection task in which they respond to specific target features. Critically, some distractor stimuli will contain the same target-defining features but combined in incorrect configurations (i.e., misbound). If feature-based filtering-out is the primary mechanism driving the attentional boost effect, then distractors containing misbound target features should still trigger the ABE. Consequently, background images presented with these distractors should exhibit enhanced memory performance, comparable to that observed when true targets are detected. Conversely, if the ABE requires correctly bound target objects, memory enhancement should occur only when genuine targets are presented, and not when distractors merely contain target features in incorrect bindings. The expected outcomes of this research will clarify whether the ABE is primarily driven by feature-level attentional filtering or by object-level target detection processes. Evidence supporting memory enhancement in the presence of misbound target features would provide strong support for the feature-based filtering-out hypothesis.