The basic level of abstraction is prioritized in early neural representations of objects

The same object can be described at multiple levels of abstraction (“parka”, “coat”, “clothing”), yet human observers consistently name objects at a mid-level of specificity known as the basic level. Little is known about the temporal dynamics involved in creating neural representations that prioritize the basic level, nor how these dynamics change with evolving task demands. In this study, observers viewed 1080 objects arranged in a three-tier category taxonomy while 64-channel EEG was recorded. Observers performed a categorical one-back task on the basic or subordinate levels in different recording sessions. We used time-resolved multiple regression to assess the utility of superordinate-, basic-, and subordinate-level categories across the scalp. We found robust use of basic-level category information starting about 80 ms after stimulus onset. Although we observed an earlier peak in posterior electrodes (168 ms) than in anterior (313 ms), the effect was observed in all regions of interest. In addition, we found that basic level feature use was negatively correlated with superordinate feature use, suggesting a competitive mechanism that sharpens category representations at the basic level. Task differences were not evident in the first 200 ms of processing but favored the task-relevant features in the 201-400 ms window. Together, this work demonstrates that the basic-level supremacy effect originates in early perceptual processing, congruent with results that show that basic-level categorization is an automatic and obligatory process.