title: Neural mechanisms of savant calendar calculating in autism: an MEG-study of few single cases.
abstract: This study contrasted the neurological correlates of calendar calculating (CC) between those individuals with autism spectrum disorder (ASD) and typically developing individuals. CC is the ability to correctly and quickly state the day of the week of a given date. Using magnetoencephalography (MEG), we presented 126 calendar tasks with dates of the present, past, and future. Event-related magnetic fields (ERF) of 3000ms duration and brain activation patterns were compared in three savant calendar calculators with ASD (ASDCC) and three typically developing calendar calculators (TYPCC). ASDCC outperformed TYPCC in correct responses, but not in answering speed. Comparing amplitudes of their ERFs, there was a main effect of group between 1000 and 3000ms, but no further effects of hemisphere or sensor location. We conducted CLARA source analysis across the entire CC period in each individual. Both ASDCC and TYPCC exhibited activation maxima in prefrontal areas including the insulae and the left superior temporal gyrus. This is in accordance with verbal fact retrieval and working memory as well as monitoring and coordination processes. In ASDCC, additional activation sites at the right superior occipital gyrus, the right precuneus, and the right putamen point to visual-spatial strategies and are in line with the preference of autistic individuals for engaging posterior regions relatively more strongly in various reasoning and problem solving tasks.
authors.affiliation: Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Silcherstr. 5, 72076 Tübingen, Germany.
authors.forename: Anna Milena
authors.initials: AM
authors.lastname: Dubischar-Krivec
authors.affiliation: Department of Women's and Children's Health, Karolinska Institute, Center of Neurodevelopmental Disorders (KIND), 17177 Stockholm, Sweden.
authors.forename: Sven
authors.initials: S
authors.lastname: Bölte
authors.affiliation: MEG-Center, University of Tübingen, Otfried-Müller-Str. 47, 72076 Tübingen, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Braun
authors.affiliation: Department of Child and Adolescent Psychiatry and Psychotherapy, J.W. Goethe University of Frankfurt, Deutschordenstr. 50, 60528 Frankfurt/M., Germany.
authors.forename: Fritz
authors.initials: F
authors.lastname: Poustka
authors.affiliation: Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Silcherstr. 5, 72076 Tübingen, Germany; Ospedale San Camillo, Istituto Ricovero e Cura a Carattere Scientifico (IRCCS), Via Alberoni 70, 30126 Venezia, Italy.
authors.forename: Niels
authors.initials: N
authors.lastname: Birbaumer
authors.affiliation: Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Silcherstr. 5, 72076 Tübingen, Germany; Center for Diagnostic Radiology and Neuroradiology, Functional Imaging Unit, University of Greifswald, Walther-Rathenau-Str. 46, 17475 Greifswald, Germany. Electronic address: nicola.neumann@uni-greifswald.de.
authors.forename: Nicola
authors.initials: N
authors.lastname: Neumann
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000503:physiopathology*; D002659:Child Development Disorders, Pervasive / Q000503:physiopathology*; D005260:Female; D006801:Humans; D015225:Magnetoencephalography; D008297:Male; D055641:Mathematical Concepts; D011939:Mental Recall / Q000502:physiology; D008875:Middle Aged; D011340:Problem Solving / Q000502:physiology*
keywords: Autism; Calendar calculation; Magnetoencephalography; Savant syndrome