Clinical neuroanatomy Dorsal and ventral language pathways in persistent developmental stuttering Vered Kronfeld-Duenias a,* , Ofer Amir b , Ruth Ezrati-Vinacour b , Oren Civier a and Michal Ben-Shachar a,c,* a The Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat-Gan, Israel b The Department of Communication Disorders, Sackler Faculty of Medicine, Tel-Aviv University, Israel c The Department of English Literature and Linguistics, Bar-Ilan University, Ramat-Gan, Israel article info Article history: Received 9 July 2015 Reviewed 6 September 2015 Revised 20 November 2015 Accepted 1 April 2016 Action editor Marco Catani Published online 12 April 2016 Keywords: White matter Diffusion imaging Stuttering Tractography Language pathways abstract Persistent developmental stuttering is a speech disorder that affects an individual's ability to fluently produce speech. While the disorder mainly manifests in situations that require language production, it is still unclear whether persistent developmental stuttering is indeed a language impairment, and if so, which language stream is implicated in people who stutter. In this study, we take a neuroanatomical approach to this question by examining the structural properties of the dorsal and ventral language pathways in adults who stutter (AWS) and fluent controls. We use diffusion magnetic resonance imaging and individualized tract identification to extract white matter volumes and diffusion properties of these tracts in samples of adults who do and do not stutter. We further quantify diffusion properties at multiple points along the tract and examine group differences within these diffusivity profiles. Our results show differences in the dorsal, but not in the ventral, language-related tracts. Specifically, AWS show reduced volume of the left dorsal stream, as well as lower anisotropy in the right dorsal stream. These data provide neuroanatomical support for the view that stuttering involves an impairment in the bidi- rectional mapping between auditory and articulatory cortices supported by the dorsal pathways, not in lexical access and semantic aspects of language processing which are thought to rely more heavily on the left ventral pathways. © 2016 Elsevier Ltd. All rights reserved. Persistent developmental stuttering is a speech disorder that affects verbal fluency in about 1% of the adult population. While the main manifestation of persistent developmental stuttering is the difficulty to fluently produce speech, it is still unclear whether this disorder is indeed a language impairment (as suggested by Bernstein Ratner, 1997, among others), or, rather, a motor impairment that manifests pri- marily in speech production, possibly due to the complexity of motor coordination required (Max, Guenther, Gracco, Ghash, & Wallace, 2004; Namasivayam & van Lieshout, 2011). The * Corresponding authors. The Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat-Gan 5290002, Israel. E-mail addresses: vered.kronfeld@gmail.com (V. Kronfeld-Duenias), michalb@mail.biu.ac.il (M. Ben-Shachar). Available online at www.sciencedirect.com ScienceDirect Journal homepage: www.elsevier.com/locate/cortex cortex 81 (2016) 79 e92 http://dx.doi.org/10.1016/j.cortex.2016.04.001 0010-9452/© 2016 Elsevier Ltd. All rights reserved.