title: Brain stimulation over Broca's area differentially modulates naming skills in neurotypical adults and individuals with Asperger's syndrome.
abstract: In the present study we tested the hypothesis that, in subjects with Asperger's syndrome (ASP), the dynamics of language-related regions might be abnormal, so that repetitive transcranial magnetic stimulation (rTMS) over Broca's area leads to differential behavioral effects as seen in neurotypical controls. We conducted a five-stimulation-site, double-blind, multiple crossover, pseudo-randomized, sham-controlled study in 10 individuals with ASP and 10 age- and gender-matched healthy subjects. Object naming was assessed before and after low-frequency rTMS of the left pars opercularis, left pars triangularis, right pars opercularis and right pars triangularis, and sham stimulation, as guided stereotaxically by each individual's brain magnetic resonance imaging. In ASP participants, naming improved after rTMS of the left pars triangularis as compared with sham stimulation, whereas rTMS of the adjacent left opercularis lengthened naming latency. In healthy subjects, stimulation of parts of Broca's area did not lead to significant changes in naming skills, consistent with published data. Overall, these findings support our hypothesis of abnormal language neural network dynamics in individuals with ASP. From a methodological point of view, this work illustrates the use of rTMS to study the dynamics of brain-behavior relations by revealing the differential behavioral impact of non-invasive brain stimulation in a neuropsychiatric disorder.
authors.affiliation: Berenson-Allen Center for Noninvasive Brain Stimulation, Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA. sfecteau@bidmc.harvard.edu
authors.forename: Shirley
authors.initials: S
authors.lastname: Fecteau
authors.forename: Sara
authors.initials: S
authors.lastname: Agosta
authors.forename: Lindsay
authors.initials: L
authors.lastname: Oberman
authors.forename: Alvaro
authors.initials: A
authors.lastname: Pascual-Leone
mesh_terms: D000328:Adult; D020817:Asperger Syndrome / Q000503:physiopathology*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D005625:Frontal Lobe / Q000502:physiology*; D006801:Humans; D007802:Language; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D009275:Names; D009483:Neuropsychological Tests; D013238:Stereotaxic Techniques; D050781:Transcranial Magnetic Stimulation / Q000379:methods*; D055815:Young Adult