Semantic Dimensions Support the Cortical Representation of Object Memorability.

Recent work in vision sciences contends that objects carry an intrinsic property called memorability that describes the likelihood that an object can be successfully encoded and later retrieved from memory. It has been shown that object memorability is supported by semantic information, but the neural correlates of this relationship are largely unexplored. The present study explores these premises and asks whether neural correlates of object memorability can be accounted for by semantic dimensions. We combine three data sets: (1) feature norms for a database of ∼1000 natural object images, (2) normative conceptual and perceptual memory data for those objects, and (3) neuroimaging data from an fMRI study collected using a subset (n = 360) of those objects. We found that object-wise memorability elicits consistent brain activation across participants in key mnemonic regions, including the hippocampus and rhinal cortex, and that the variance in this neural activity is mediated by the semantic factors describing these images. We propose that the features of memorable images may be facilitating memory formation by more deeply engaging encoding processes.