title: Is functional integration of resting state brain networks an unspecific biomarker for working memory performance?
abstract: Is there one optimal topology of functional brain networks at rest from which our cognitive performance would profit? Previous studies suggest that functional integration of resting state brain networks is an important biomarker for cognitive performance. However, it is still unknown whether higher network integration is an unspecific predictor for good cognitive performance or, alternatively, whether specific network organization during rest predicts only specific cognitive abilities. Here, we investigated the relationship between network integration at rest and cognitive performance using two tasks that measured different aspects of working memory; one task assessed visual-spatial and the other numerical working memory. Network clustering, modularity and efficiency were computed to capture network integration on different levels of network organization, and to statistically compare their correlations with the performance in each working memory test. The results revealed that each working memory aspect profits from a different resting state topology, and the tests showed significantly different correlations with each of the measures of network integration. While higher global network integration and modularity predicted significantly better performance in visual-spatial working memory, both measures showed no significant correlation with numerical working memory performance. In contrast, numerical working memory was superior in subjects with highly clustered brain networks, predominantly in the intraparietal sulcus, a core brain region of the working memory network. Our findings suggest that a specific balance between local and global functional integration of resting state brain networks facilitates special aspects of cognitive performance. In the context of working memory, while visual-spatial performance is facilitated by globally integrated functional resting state brain networks, numerical working memory profits from increased capacities for local processing, especially in brain regions involved in working memory performance.
authors.affiliation: Biological Psychology Lab, Department of Psychology, European Medical School, Carl von Ossietzky Universität, 26111 Oldenburg, Germany. Electronic address: mohsen.alavash@uni-oldenburg.de.
authors.forename: Mohsen
authors.initials: M
authors.lastname: Alavash
authors.affiliation: Department of Psychology and Sport Sciences, Westfälische Wilhelms-Universität, 48149 Münster, Germany. Electronic address: doebler@uni-muenster.de.
authors.forename: Philipp
authors.initials: P
authors.lastname: Doebler
authors.affiliation: Department of Psychology and Sport Sciences, Westfälische Wilhelms-Universität, 48149 Münster, Germany. Electronic address: holling@uni-muenster.de.
authors.forename: Heinz
authors.initials: H
authors.lastname: Holling
authors.affiliation: Biological Psychology Lab, Department of Psychology, European Medical School, Carl von Ossietzky Universität, 26111 Oldenburg, Germany. Electronic address: christiane.thiel@uni-oldenburg.de.
authors.forename: Christiane M
authors.initials: CM
authors.lastname: Thiel
authors.affiliation: Biological Psychology Lab, Department of Psychology, European Medical School, Carl von Ossietzky Universität, 26111 Oldenburg, Germany. Electronic address: carsten.giessing@uni-oldenburg.de.
authors.forename: Carsten
authors.initials: C
authors.lastname: Gießing
mesh_terms: D000328:Adult; D015415:Biomarkers; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D009415:Nerve Net / Q000502:physiology*; D055815:Young Adult
chemical_list: D015415:Biomarkers
keywords: Computational span; Graph theory; Network integration; Resting state fMRI; Visual–spatial working memory