RT Journal Article
SR Electronic
T1 Pinpointing the neural signatures of single-exposure visual familiarity
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2020.07.01.182881
DO 10.1101/2020.07.01.182881
A1 Vahid Mehrpour
A1 Travis Meyer
A1 Eero P. Simoncelli
A1 Nicole C. Rust
YR 2020
UL http://biorxiv.org/content/early/2020/07/02/2020.07.01.182881.abstract
AB Memories of the images that we have seen are thought to be reflected in the reduction of neural responses in high-level visual areas such as inferotemporal (IT) cortex, a phenomenon known as repetition suppression (RS). We challenged this hypothesis with a task that required rhesus monkeys to report image familiarity while ignoring variations in contrast, a stimulus attribute that is also known to modulate the overall IT response. The monkeys’ behavior was largely contrast-invariant, contrary to the predictions of the RS encoding scheme, which could not distinguish response familiarity from changes in contrast. However, the monkeys’ behavioral patterns were well predicted by a linearly decodable variant in which the total spike count is corrected for contrast modulation. These results suggest that the IT neural activity pattern that best aligns with single-exposure visual familiarity behavior is not RS but rather “sensory referenced suppression (SRS)”: reductions in IT population response magnitude, corrected for sensory modulation.Competing Interest StatementThe authors have declared no competing interest.