Cell Press, Neuron, 2(72), p. 404-416, 2011
DOI: 10.1016/j.neuron.2011.08.026
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We present a high-dimensional model of the representational space in human ventral temporal (VT) cortex in which dimensions are response-tuning functions that are common across individuals and patterns of response are modeled as weighted sums of basis patterns associated with these response-tunings. We map response pattern vectors, measured with fMRI, from individual subjects’ voxel spaces into this common model space using a new method, ‘hyperalignment’. Hyperalignment parameters based on responses during one experiment – movie-viewing – identified 35 common response-tuning functions that captured fine-grained distinctions among a wide range of stimuli in the movie and in two category perception experiments. Between-subject classification (BSC, multivariate pattern classification based on other subjects’ data) of response pattern vectors in common model space greatly exceeded BSC of anatomically-aligned responses and matched within-subject classification. Results indicate that population codes for complex visual stimuli in VT cortex are based on response-tuning functions that are common across individuals.