Representation of Perceived Object Shape by the Human Lateral Occipital Complex

TLDR

The lateral occipital complex is known to support object recognition, yet it is unclear if it encodes low‑level image features or higher‑level perceived shape. Using an event‑related fMRI adaptation paradigm, the authors compared responses to successive stimulus pairs, interpreting reduced activation for identical pairs as evidence of a shared neural representation invariant to the intervening change. They observed LOC adaptation when perceived shape was identical but contours varied, but not when contours matched yet shape differed, demonstrating that LOC encodes higher‑level shape rather than simple image features.

Abstract

The human lateral occipital complex (LOC) has been implicated in object recognition, but it is unknown whether this region represents low-level image features or perceived object shape. We used an event-related functional magnetic resonance imaging adaptation paradigm in which the response to pairs of successively presented stimuli is lower when they are identical than when they are different. Adaptation across a change between the two stimuli in a pair provides evidence for a common neural representation invariant to that change. We found adaptation in the LOC when perceived shape was identical but contours differed, but not when contours were identical but perceived shape differed. These data indicate that the LOC represents not simple image features, but rather higher level shape information.