The expression of established cognitive brain states stabilizes with working memory development
Abstract
We present results from a longitudinal study conducted over 10 years in a sample of 126 8-33 year olds demonstrating that adolescent development of working memory is supported by decreased variability in the amplitude of expression of whole brain states of task-related activity. fMRI analyses reveal that putative gain signals affecting maintenance and retrieval aspects of working memory processing stabilize during adolescence, while those affecting sensorimotor processes do not. We show that trial-to-trial variability in the reaction time and accuracy of eye-movements during a memory guided saccade task are related to fluctuations in the amplitude of expression of task-related brain states, or brain state variability, and also provide evidence that individual developmental trajectories of reaction time variability are related to individual trajectories of brain state variability. These observations demonstrate that underlying the maturation of cognition through adolescence is the stabilization of widespread gain signals affecting already available cognitive processes.
Data availability
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Data from: The expression of established cognitive brain states stabilizes with working memory development.Available at Dryad Digital Repository under a CC0 Public Domain Dedication.
Article and author information
Author details
Funding
National Institutes of Health (5R01MH067924)
- David Florentino Montez
- Finnegan J Calabro
- Beatriz Luna
Staunton Farm Foundation
- Finnegan J Calabro
- Beatriz Luna
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: Participants and/or their legal guardians provided informed consent before participating in this study. Experimental procedures for this study complied with the Code of Ethics of the World Medical Association (1964; Declaration of Helsinki) and the Institutional Review Board at the University of Pittsburgh. Subjects were paid for their participation in the study.
Copyright
© 2017, Montez 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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