title: Segregation of anterior temporal regions critical for retrieving names of unique and non-unique entities reflects underlying long-range connectivity.
abstract: Lesion-deficit studies support the hypothesis that the left anterior temporal lobe (ATL) plays a critical role in retrieving names of concrete entities. They further suggest that different regions of the left ATL process different conceptual categories. Here we test the specificity of these relationships and whether the anatomical segregation is related to the underlying organization of white matter connections. We reanalyzed data from a previous lesion study of naming and recognition across five categories of concrete entities. In voxelwise logistic regressions of lesion-deficit associations, we formally incorporated measures of disconnection of long-range association fiber tracts (FTs) and covaried for recognition and non-category-specific naming deficits. We also performed fiber tractwise analyses to assess whether damage to specific FTs was preferentially associated with category-selective naming deficits. Damage to the basolateral ATL was associated with naming deficits for both unique (famous faces) and non-unique entities, whereas the damage to the temporal pole was associated with naming deficits for unique entities only. This segregation pattern remained after accounting for comorbid recognition deficits or naming deficits in other categories. The tractwise analyses showed that damage to the uncinate fasciculus (UNC) was associated with naming impairments for unique entities, while damage to the inferior longitudinal fasciculus (ILF) was associated with naming impairments for non-unique entities. Covarying for FT transection in voxelwise analyses rendered the cortical association for unique entities more focal. These results are consistent with the partial segregation of brain system support for name retrieval of unique and non-unique entities at both the level of cortical components and underlying white matter fiber bundles. Our study reconciles theoretic accounts of the functional organization of the left ATL by revealing both category-related processing and semantic hub sectors.
authors.affiliation: Department of Psychology, University of Washington, Seattle, WA, USA; Department of Radiology, University of Washington School of Medicine, Seattle, WA, USA; Integrated Brain Imaging Center, University of Washington Medical Center, Seattle, WA, USA.
authors.forename: Sonya
authors.initials: S
authors.lastname: Mehta
authors.affiliation: Department of Radiology, University of Washington School of Medicine, Seattle, WA, USA; Integrated Brain Imaging Center, University of Washington Medical Center, Seattle, WA, USA.
authors.forename: Kayo
authors.initials: K
authors.lastname: Inoue
authors.affiliation: Grenoble Institut des Neurosciences, Inserm U 836 - UJF - CEA - CHU, Grenoble, France.
authors.forename: David
authors.initials: D
authors.lastname: Rudrauf
authors.affiliation: Departments of Psychology and Neurology, University of Southern California, Los Angeles, CA, USA; Brain and Creativity Institute, University of Southern California, Los Angeles, CA, USA; Dornsife Cognitive Neuroimaging Center, University of Southern California, Los Angeles, CA, USA.
authors.forename: Hanna
authors.initials: H
authors.lastname: Damasio
authors.affiliation: Departments of Neurology and Psychology, University of Iowa, Iowa City, IA, USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Tranel
authors.affiliation: Department of Psychology, University of Washington, Seattle, WA, USA; Department of Radiology, University of Washington School of Medicine, Seattle, WA, USA; Integrated Brain Imaging Center, University of Washington Medical Center, Seattle, WA, USA; Department of Neurology, University of Washington Medical Center, Seattle, WA, USA. Electronic address: tgrabow@uw.edu.
authors.forename: Thomas
authors.initials: T
authors.lastname: Grabowski
mesh_terms: D000328:Adult; D001931:Brain Mapping / Q000379:methods; D005145:Face / Q000473:pathology; D006801:Humans; D008568:Memory / Q000502:physiology; D009275:Names; D009483:Neuropsychological Tests; D021641:Recognition, Psychology / Q000502:physiology*; D012660:Semantics; D013702:Temporal Lobe / Q000502:physiology*
keywords: Anterior temporal cortex; Fiber tract disconnection; Lesion–deficit relationship; Lexical retrieval; Naming; Object recognition