Shared and Distinct Object Spaces in Human and Macaque Inferotemporal Cortex

Inferotemporal (IT) cortex is central to primate object vision, yet we still lack a systematic understanding of which aspects of its functional organization generalize across humans and macaques and which are species-specific. Here, we compared large-scale macaque multi-unit activity and human fMRI responses to 8,640 naturalistic object images shown to both species. Using multivariate cross-species alignment, we identified a shared high-dimensional geometry with representational axes that capture both visual properties and conceptual structure. A factorization of this continuous space further resolved a large set of interpretable dimensions shared across species. Beyond these commonalities, contrasting the within-species spaces revealed systematic asymmetries related to visual features, living and non-living categories, and higher-level concepts. Together, these findings provide a data-driven account of primate IT organization across object space, clarify the scope and limits of cross-species comparability, and establish cross-species alignment as a framework for mapping shared and species-specific dimensions.