title: Metabolic and structural connectivity within the default mode network relates to working memory performance in young healthy adults.
abstract: Studies of functional connectivity suggest that the default mode network (DMN) might be relevant for cognitive functions. Here, we examined metabolic and structural connectivity between major DMN nodes, the posterior cingulate (PCC) and medial prefrontal cortex (MPFC), in relation to normal working memory (WM). DMN was captured using independent component analysis of [18F]fluorodeoxyglucose positron emission tomography (FDG-PET) data from 35 young healthy adults (27.1 ± 5.1 years). Metabolic connectivity, a correlation between FDG uptake in PCC and MPFC, was examined in groups of subjects with (relative to median) low (n=18) and high (n=17) performance on digit span backward test as an index of verbal WM. In addition, fiber tractography based on PCC and MPFC nodes as way points was performed in a subset of subjects. FDG uptake in the DMN nodes did not differ between high and low performers. However, significantly (p=0.01) lower metabolic connectivity was found in the group of low performers. Furthermore, as compared to high performers, low performers showed lower density of the left superior cingulate bundle. Verbal WM performance is related to metabolic and structural connectivity within the DMN in young healthy adults. Metabolic connectivity as quantified with FDG-PET might be a sensitive marker of the normal variability in some cognitive functions.
authors: Department of Psychiatry and Psychotherapy, University Medical Center Mainz, Mainz, Germany. igor.yakushev@lrz.tum.de
authors: Igor
authors: I
authors: Yakushev
authors: Gael
authors: G
authors: Chételat
authors: Florian U
authors: FU
authors: Fischer
authors: Brigitte
authors: B
authors: Landeau
authors: Christine
authors: C
authors: Bastin
authors: Armin
authors: A
authors: Scheurich
authors: Audrey
authors: A
authors: Perrotin
authors: Mohamed Ali
authors: MA
authors: Bahri
authors: Alexander
authors: A
authors: Drzezga
authors: Francis
authors: F
authors: Eustache
authors: Mathias
authors: M
authors: Schreckenberger
authors: Andreas
authors: A
authors: Fellgiebel
authors: Eric
authors: E
authors: Salmon
mesh_terms: D000328:Adult; D001921:Brain / Q000502:physiology*; D063132:Connectome / Q000379:methods*; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics*; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D009415:Nerve Net / Q000033:anatomy & histology* / Q000502:physiology*; D049268:Positron-Emission Tomography / Q000379:methods; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D015398:Signal Transduction / Q000502:physiology*
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18