The independence of endogenous attentional orienting and object individuation

Object individuation is the process whereby the brain infers that dynamic input reflects multiple discrete objects, rather than a single, continuing object over time. Object substitution masking is a popular method for operationalizing object individuation inferences in the laboratory. Although object substitution masking was historically thought to interact with attentional processes, an emerging body of literature indicates that this form of visual masking is impervious to some attentional manipulations. However, one form of attention that has not been systematically studied in relation to object-substitution masking is endogenous attentional orienting. This is important because in other domains, endogenous attentional orienting has been found to have qualitatively distinct effects from other forms of attention, including impacting visual perception when other forms of attention do not. Therefore, if attention does interact with object individuation processes, then endogenous attentional orienting is the most likely candidate mechanism for such a relationship. Here, therefore, the impact of endogenous attentional on objectsubstitution masking was tested. Across 2 experiments, although endogenous attentional orienting impacted overall target perception, it had no impact on object substitution masking. This implies that object individuation inferences are indeed independent of attention.