A Data-Driven Analysis of the Perceptual and Neural Responses to Natural Objects Reveals Organizing Principles of...

A key challenge in understanding the functional organization of the visual cortex stems from the fact that only a small proportion of the objects experienced during natural viewing can be presented in a typical experiment. This constraint often leads to experimental designs that compare responses to objects from experimenter-defined stimulus conditions, potentially limiting the interpretation of the data. To overcome this issue, we used images from the THINGS initiative, which provides a systematic sampling of natural objects. A data-driven analysis was then applied to reveal the functional organization of the visual brain, incorporating both perceptual and neural responses to these objects. Perceptual properties of the objects were taken from an analysis of similarity judgments, and neural properties were taken from whole-brain fMRI responses to the same objects. Partial least squares regression (PLSR) was then used to predict neural responses across the brain from the perceptual properties while simultaneously applying dimensionality reduction. The PLSR model accurately predicted neural responses across the visual cortex using only a small number of components. These components revealed smooth, graded neural topographies, which were similar in both hemispheres and captured a variety of object properties including animacy, real-world size, and object category. However, they did not accord in any simple way with previous theoretical perspectives on object perception. Instead, our findings suggest that the visual cortex encodes information in a statistically efficient manner, reflecting natural variability among objects.