eLife Assessment
This valuable study demonstrates that it is possible to decode information about characters and locations from single-unit responses in the human brain to a narrative movie, using a convincing technical approach to capture information in population-level dynamics. The study introduces an exciting dataset of single-unit responses in humans during a naturalistic and dynamic movie stimulus, with recordings from multiple regions within the medial temporal lobe. Using both a traditional firing-rate analysis as well as a population decoding analysis to connect these neural responses to the visual content of the movie, they show that in this dataset, the decoding of semantic scene features (e.g., the person currently on screen), but not scene transitions, is surprisingly driven by classically non-responsive neurons. Based on these findings, the authors argue that dynamic naturalistic semantic information may be processed within the medial temporal lobe at the population level.