The inferior parietal lobe (IPL) is a key neural substrate underlying diverse mental processes, from basic attention to language and social cognition, that define human interactions. Its putative domain-global role appears to tie into poorly understood differences between cognitive domains in both hemispheres. Across attentional, semantic, and social cognitive tasks, our study explored functional specialization within the IPL. The task specificity of IPL subregion activity was substantiated by distinct predictive signatures identified by multivariate pattern-learning algorithms. Moreover, the left and right IPL exerted domain-specific modulation of effective connectivity among their subregions. Task-evoked functional interactions of the anterior and posterior IPL subregions involved recruitment of distributed cortical partners. While anterior IPL subregions were engaged in strongly lateralized coupling links, both posterior subregions showed more symmetric coupling patterns across hemispheres. Our collective results shed light on how under-appreciated functional specialization in the IPL supports some of the most distinctive human mental capacities.
Preprocessed fMRI data and behavioral data are publicly available at the Open Science Framework doi:10.17605/OSF.IO/9NDHP .
FuncSegOpen Science Framework, 9NDHP.
- Danilo Bzdok
- Danilo Bzdok
- Gesa Hartwigsen
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Human subjects: The study was performed according to the guidelines of the Declaration of Helsinki and approved by the Ethics Committee of the Medical Faculty of the University of Leipzig, Germany (282/16-eh). Written informed consent was obtained from all subjects before the experiment.
- Dwight Kravitz, The George Washington University, United States
© 2021, Numssen 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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