Neural systems maintain stable operating ranges by engaging adaptation mechanisms such as gain control or homeostatic plasticity. Prior demonstrations of sensory adaptation typically used extreme or narrowly targeted stimuli. The present work examines whether similar adaptive processes occur under more naturalistic, ecologically valid conditions—specifically during and after viewing short movie clips.
The authors report a widespread adaptation phenomenon across human cortex that emerges following naturalistic movie watching. They label this post-stimulus phenomenon the Movie After-Effect (MvAE) and frame it as a candidate homeostatic response to prolonged, complex sensory input.
Analyses were performed on the Human Connectome Project (HCP) fMRI data set described in the source. In this data set, 170 participants watched 14 movie clips; each clip was followed by a rest period. The study evaluated cortical responses across a parcellation of cortical regions and assessed activity changes during movies and in the subsequent rest intervals.
Across the cortical parcels that exhibited significant stimulus-driven activation during the movies, the MvAE was highly prevalent. Specifically, out of 251 activated cortical regions, 218 regions (87%) showed the movie-induced adaptation effect in the post-movie rest periods. These observations indicate a broad cortical phenomenon rather than a localized response restricted to primary sensory areas.
Within individual cortical regions, the adaptation manifested as a population-level inversion of voxel responses. Voxels that were highly activated at the end of a movie subsequently showed activity that dropped below baseline during the following rest. Conversely, voxels that were persistently inactivated during the movie exhibited increased activation above baseline during rest. Critically, the magnitude of the post-movie activity decrease was proportional to the voxel's activation level at the end of the movie, yielding a consistent voxel-population inversion effect across regions.
This within-region inversion suggests a redistribution or rebalancing of activity across voxel populations after sustained naturalistic stimulation rather than a uniform suppression or facilitation across all voxels.
The MvAE pattern was sufficiently specific to enable decoding: the study reports that it was possible to decode which particular rest period followed which movie clip based on the post-movie activity pattern. In other words, the rest-period signatures carried information tied to the identity of the immediately preceding movie stimulus.
The authors interpret the MvAE as evidence that cortical neurons dynamically adjust their gain after prolonged naturalistic stimulation to restore homeostatic balance. The proportional relation between end-of-movie activation and subsequent drop below baseline supports a model in which stronger recent activation drives stronger compensatory downregulation during rest, and vice versa for persistently low-activity voxels.
To conceptualize the process, the authors draw an analogy to batch instance normalization techniques used in artificial neural networks. In this view, the cortex may perform a form of population-level normalization across voxels after batches of complex sensory input, adjusting activity scales to maintain stable operating ranges.
The authors note that while the MvAE is ubiquitous under the tested naturalistic conditions, its cognitive consequences are not yet known. Specifically, whether the MvAE influences memory consolidation, perceptual aftereffects, attention, or other cognitive processes remains to be determined. The source explicitly states that additional cognitive and memory-related implications are open questions for future research.
This report is a preprint posted on bioRxiv on August 18, 2026. As noted by the authors, the manuscript has not undergone peer review. The abstract supplies the principal findings and interpretations, but additional methodological details, full statistical reporting, temporal dynamics, precise region-by-region maps, and replication analyses are not provided in the source summary. Readers should consult the full preprint for complete methods and results and treat conclusions as preliminary until peer-reviewed confirmation.
The authors declared no competing interests.
Using HCP fMRI data from 170 participants who watched 14 movie clips, the authors document a widespread post-movie adaptation process (the Movie After-Effect, MvAE) across many cortical regions. The effect includes a reproducible voxel-population inversion—highly activated voxels decrease below baseline, while persistently inactive voxels increase above baseline—with magnitude proportional to prior activation. The MvAE permits decoding of which movie preceded a rest period and is interpreted as a homeostatic gain adjustment analogous to normalization procedures in artificial networks. Whether this ubiquitous adaptation has further cognitive or memory-related roles remains to be investigated in follow-up, peer-reviewed work.