Thalamocortical contribution to cognitive task activity
Abstract
Thalamocortical interaction is a ubiquitous functional motif in the mammalian brain. Previously (Hwang et al., 2021), we reported that lesions to network hubs in the human thalamus are associated with multi-domain behavioral impairments in language, memory, and executive functions. Here we show how task-evoked thalamic activity are organized to support these broad cognitive abilities. We analyzed functional MRI data from human subjects that performed 127 tasks encompassing a broad range of cognitive representations. We first investigated the spatial organization of task-evoked activity and found a basis set of activity patterns evoked to support processing needs of each task. Specifically, the anterior, medial, and posterior-medial thalamus exhibit hub-like activity profiles that are suggestive of broad functional participation. These thalamic task hubs overlapped with network hubs interlinking cortical systems. To further determine the cognitive relevance of thalamic activity and thalamocortical functional connectivity, we built a data-driven thalamocortical model to test whether thalamic activity can be used to predict cortical task activity. The thalamocortical model predicted task-specific cortical activity patterns, and outperformed comparison models built on cortical, hippocampal, and striatal regions. Simulated lesions to low-dimensional, multi-task thalamic hub regions impaired task activity prediction. This simulation result was further supported by profiles of neuropsychological impairments in human patients with focal thalamic lesions. In summary, our results suggest a general organizational principle of how the human thalamocortical system supports cognitive task activity.
Data availability
Raw data are available at OpenNeuro.org (https://openneuro.org/datasets/ds002105/ and https://openneuro.org/datasets/ds002306/). Code and data are available at (https://github.com/HwangLabNeuroCogDynamics/ThalamicTaskHubs)
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multi-domain task batterydoi:10.18112/openneuro.ds002105.v1.1.0.
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Over 100 Task fMRI Datasetdoi:10.18112/openneuro.ds002306.v1.0.3.
Article and author information
Author details
Funding
National Institutes of Health (R01MH122613)
- Kai Hwang
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: All participants gave written informed consent, and the study was approved by the University of Iowa Institutional Review Board (IRB protocol #200105018).
Copyright
© 2022, Hwang 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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