A partially nested cortical hierarchy of neural states underlies event segmentation in the human brain
- Radboud University Nijmegen, Netherlands
- Brock University, Canada
Abstract
A fundamental aspect of human experience is that it is segmented into discrete events. This may be underpinned by transitions between distinct neural states. Using an innovative data-driven state segmentation method, we investigate how neural states are organized across the cortical hierarchy and where in the cortex neural state boundaries and perceived event boundaries overlap. Our results show that neural state boundaries are organized in a temporal cortical hierarchy, with short states in primary sensory regions, and long states in lateral and medial prefrontal cortex. State boundaries are shared within and between groups of brain regions that resemble well-known functional networks. Perceived event boundaries overlap with neural state boundaries across large parts of the cortical hierarchy, particularly when those state boundaries demarcate a strong transition or are shared between brain regions. Taken together, these findings suggest that a partially nested cortical hierarchy of neural states forms the basis of event segmentation.
Data availability
*The data used in this project can be requested via -https://camcan-archive.mrc-cbu.cam.ac.uk/dataaccess/*The code used to generate the results in the paper is available at - https://github.com/lgeerligs/NestedHierarchy*The improvements to our GSBS algorithm that are presented in this paper are released in a Python package: https://pypi.org/project/statesegmentation/
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Data from the Cambridge Centre for Ageing and Neuroscience10.1186/s12883-014-0204-1.
Article and author information
Author details
Funding
Nederlandse Organisatie voor Wetenschappelijk Onderzoek (VI.Vidi.201.150)
- Linda Geerligs
Natural Sciences and Engineering Research Council of Canada (RGPIN-2017-03804)
- Karen L Campbell
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: This Cambridge Centre for Ageing Neuroscience study was conducted in compliance with the Helsinki Declaration, and has been approved by the local ethics committee, Cambridgeshire 2 Research Ethics Committee (now East of England - Cambridge Central; reference: 10/H0308/50). Participants gave written informed consent prior to participating in the study.
Copyright
© 2022, Geerligs et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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A partially nested cortical hierarchy of neural states underlies event segmentation in the human brain
eLife 11:e77430.
https://doi.org/10.7554/eLife.77430
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