Multidimensional object properties are dynamically represented in the human brain

Our visual world consists of an immense number of unique objects and yet, we are easily able to identify, distinguish, interact, and reason about the things we see within several hundred milliseconds. This requires that we flexibly integrate and focus on different object properties to support specific behavioral goals. In the current study, we examined how these rich object representations unfold in the human brain by modelling time-resolved MEG signals evoked by viewing thousands of objects. Using millions of behavioral judgments to guide our understanding of the neural representation of the object space, we find distinct temporal profiles across the object dimensions. These profiles fell into two broad types with either a distinct and early peak (~150 ms) or a slow rise to a late peak (~300 ms). Further, the early effects are stable across participants in contrast to later effects which show more variability across people. This highlights that early peaks may carry stimulus-specific and later peaks subject-specific information. Given that the dimensions with early peaks seem to be primarily visual dimensions and those with later peaks more conceptual, our results suggest that conceptual processing is more variable across people. Together, these data provide a comprehensive account of how a variety of object properties unfold in the human brain and contribute to the rich nature of object vision.