Traditional neurological models of language were based on a single neural pathway (the dorsal pathway underpinned by the arcuate fasciculus). Contemporary neuroscience indicates that anterior temporal regions and the "ventral" language pathway also make a significant contribution, yet there is no computationally-implemented model of the dual pathway, nor any synthesis of normal and aphasic behavior. The "Lichtheim 2" model was implemented by developing a new variety of computational model which reproduces and explains normal and patient data but also incorporates neuroanatomical information into its architecture. By bridging the "mind-brain" gap in this way, the resultant "neurocomputational" model provides a unique opportunity to explore the relationship between lesion location and behavioral deficits, and to provide a platform for simulating functional neuroimaging data.

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Semantic memory is a crucial higher cortical function that codes the meaning of objects and words, and when impaired after neurological damage, patients are left with significant disability. Investigations of semantic dementia have implicated the anterior temporal lobe (ATL) region, in general, as crucial for multimodal semantic memory. The potentially crucial role of the ventral ATL subregion has been emphasized by recent functional neuroimaging studies, but the necessity of this precise area has not been selectively tested. The implantation of subdural electrode grids over this subregion, for the presurgical assessment of patients with partial epilepsy or brain tumor, offers the dual yet rare opportunities to record cortical local field potentials while participants complete semantic tasks and to stimulate the functionally identified regions in the same participants to evaluate the necessity of these areas in semantic processing. Across 6 patients, and utilizing a variety of semantic assessments, we evaluated and confirmed that the anterior fusiform/inferior temporal gyrus is crucial in multimodal, receptive, and expressive, semantic processing.