Diverse temporal dynamics of repetition suppression revealed by intracranial recordings in human ventral temporal cortex [article]

Vinitha Rangarajan, Corentin Jacques, Robert Knight, Kevin Weiner, Kalanit Grill-Spector
2019 bioRxiv   pre-print
Repeated stimulus presentations commonly produce decreased neural responses - a phenomenon known as repetition suppression (RS) or adaptation - in ventral temporal cortex (VTC) in humans and nonhuman primates. However, the temporal features of RS in human VTC are not well understood. To fill this gap in knowledge, we utilized the precise spatial localization and high temporal resolution of electrocorticography (ECoG) from 9 human subjects implanted with intracranial electrodes in VTC. Subjects
more » ... iewed non-repeated and repeated images of faces with (long-lagged) intervening stimuli between repeats. We report three main findings: (i) robust RS occurs for VTC activity in high-frequency broadband (HFB), but not lower frequency bands, (ii) RS is associated with lower peak magnitude, lower total responses of the HFB signal, and earlier peak responses, and (iii) RS effects occur early within initial stimulus processing and persist for the entire stimulus duration. We discuss these findings in the context of early and late components of visual perception, as well as theoretical models of RS in which these ECoG data empirically support timing predictions stemming from the facilitation model of RS in human VTC for the first time.
doi:10.1101/711523 fatcat:zyge464pkbeunno2op7doiiyoy