Licata, Abigail E.Zhao, YiHerrmann, OliviaHillis, Argye E.Desmond, JohnOnyike, ChiadiTsapkini, Kyrana2023-10-172023-10-172023Licata AE, Zhao Y, Herrmann O, et al. Sex differences in effects of tDCS and language treatments on brain functional connectivity in primary progressive aphasia. Neuroimage Clin. 2023;37:103329. doi:10.1016/j.nicl.2023.103329https://hdl.handle.net/1805/36389Primary Progressive Aphasia (PPA) is a neurodegenerative disorder primarily affecting language functions. Neuromodulatory techniques (e.g., transcranial direct current stimulation, active-tDCS) and behavioral (speech-language) therapy have shown promising results in treating speech and language deficits in PPA patients. One mechanism of active-tDCS efficacy is through modulation of network functional connectivity (FC). It remains unknown how biological sex influences FC and active-tDCS or language treatment(s). In the current study, we compared sex differences, induced by active-tDCS and language therapy alone, in the default mode and language networks, acquired during resting-state fMRI in 36 PPA patients. Using a novel statistical method, the covariate-assisted-principal-regression (CAPs) technique, we found sex and age differences in FC changes following active-tDCS. In the default mode network (DMN): (1) men (in both conditions) showed greater FC in DMN than women. (2) men who received active-tDCS showed greater FC in the DMN than men who received language-treatment only. In the language network: (1) women who received active-tDCS showed significantly greater FC across the language network than women who received sham-tDCS. As age increases, regardless of sex and treatment condition, FC in language regions decreases. The current findings suggest active-tDCS treatment in PPA alters network-specific FC in a sex-dependent manner.en-USAttribution-NonCommercial-NoDerivatives 4.0 InternationalSex differencesLanguage therapyPrimary progressive aphasia (PPA)Transcranial direct current stimulation (tDCS)Functional connectivityArticle