Abstract
Decades of research have provided evidence that high-level conceptual information can influence attentional allocation when task-relevant. Accumulating evidence in recent years has also demonstrated that the influence of semantic information on attention is not restricted to task-relevant situations (Shomstein, Malcolm, & Nah, 2019). These results demonstrate that high-level associations in the real-world automatically and continuously influence attentional processing. So far, however, the definition of “semantic” within the attentional literature has only been broadly construed. However, within the concept literature, semantic associations are divided into two types: taxonomic (i.e., similar intrinsic features, dog - bear) and thematic (i.e., common co-occurrence, dog - leash) relationships. This division is supported by behavioral and neural evidence (Mirman, Landridgan, & Britt, 2017). Here, we investigate whether attentional allocation is sensitive to the taxonomic and thematic relationships between objects. Participants were presented with two objects appearing on either side of fixation. The two objects were taxonomically, thematically, or neutrally related to one another. After 750ms, a Gabor patch appeared in the center of each object. Participants reported whether the orientation of two target Gabors were matched or mismatched. Shortest response times were observed when the objects were thematically-related, followed by the taxonomically-related and neutrally-related objects; all were significantly different from each other. When the object presentation time was shortened (500 ms), however, there was no difference between any of the three conditions. These results suggest that the efficiency of attentional allocation is sensitive to the specific type of semantic relationships and evolves over time (Malcolm, Rattinger, & Shomstein, 2016). Thus, while the semantic influence of task-irrelevant taxonomic and thematic relationships between objects follow a similar time course, the amount of influence depends on the type of relationship. This suggests that the distribution of attention is sensitive to the pre-existing organization of semantic networks in the brain.