Emmanuel Mandonnet1, Guillaume Herbet2, Sylvie Moritz-Gasser2, Isabelle Poisson2, François Rheault2, Hugues Duffau2. 1. From the Department of Neurosurgery (E.M., I.P., F.R.), Lariboisière Hospital; University Paris 7 (E.M.); Frontlab (E.M.), INSERM, Institut du Cerveau et de la Moelle, Paris, France; Sherbrook Connectivity Imaging Lab (F.R.), Department of Computer Science, Faculty of Sciences, Université de Sherbrook, Quebec, Canada; Department of Neurosurgery (G.H., S.M.-G., H.D.), Hôpital Gui de Chauliac, Montpellier Medical University Center; Institute of Neuroscience of Montpellier (G.H., S.M.-G., H.D.), INSERM U1051; and University of Montpellier (G.H., S.M.-G., H.D.), Montpellier, France. emmanuel.mandonnet@aphp.fr. 2. From the Department of Neurosurgery (E.M., I.P., F.R.), Lariboisière Hospital; University Paris 7 (E.M.); Frontlab (E.M.), INSERM, Institut du Cerveau et de la Moelle, Paris, France; Sherbrook Connectivity Imaging Lab (F.R.), Department of Computer Science, Faculty of Sciences, Université de Sherbrook, Quebec, Canada; Department of Neurosurgery (G.H., S.M.-G., H.D.), Hôpital Gui de Chauliac, Montpellier Medical University Center; Institute of Neuroscience of Montpellier (G.H., S.M.-G., H.D.), INSERM U1051; and University of Montpellier (G.H., S.M.-G., H.D.), Montpellier, France.
Abstract
OBJECTIVE: The present study aimed to elucidate the neural correlates of the deafferentation cognitive model of verbal perseveration (VP) by analyzing the connectomics of the sites where electric stimulation elicited VP during awake left glioma surgery. METHODS: We retrospectively reviewed the anatomic sites that generated VP when electrically stimulated in a series of 21 patients operated on while awake for a left glioma. Each stimulation point was manually located on the postoperative MRI and then registered to the Montreal Neurological Institute template. Connectomics of these sites were further analyzed with Tractotron and disconnectome maps. RESULTS: VP stimulation sites were located within the white matter surrounding the posterosuperior head of the caudate nucleus, as well as within the white matter of the external capsule and the superolateral wall of the temporal horn of the ventricle. Furthermore, Tractotron and disconnectome maps revealed the connectome of these stimulation sites: the inferior fronto-occipital fasciculus, frontostriatal tract, and anterior thalamic radiations. CONCLUSION: On the basis of these results and other data, we propose the following anatomic implementation of the deafferentation cognitive model: the lexico-semantic system, comprising different areas linked together through direct cortico-cortical connections, sends information to the striatum; the striato-thalamic system acts as a tunable filter of this lexico-semantic input; and the thalamus projects back to the lexico-semantic system, amplifying the targeted response and inhibiting its competitors.
OBJECTIVE: The present study aimed to elucidate the neural correlates of the deafferentation cognitive model of verbal perseveration (VP) by analyzing the connectomics of the sites where electric stimulation elicited VP during awake left glioma surgery. METHODS: We retrospectively reviewed the anatomic sites that generated VP when electrically stimulated in a series of 21 patients operated on while awake for a left glioma. Each stimulation point was manually located on the postoperative MRI and then registered to the Montreal Neurological Institute template. Connectomics of these sites were further analyzed with Tractotron and disconnectome maps. RESULTS:VP stimulation sites were located within the white matter surrounding the posterosuperior head of the caudate nucleus, as well as within the white matter of the external capsule and the superolateral wall of the temporal horn of the ventricle. Furthermore, Tractotron and disconnectome maps revealed the connectome of these stimulation sites: the inferior fronto-occipital fasciculus, frontostriatal tract, and anterior thalamic radiations. CONCLUSION: On the basis of these results and other data, we propose the following anatomic implementation of the deafferentation cognitive model: the lexico-semantic system, comprising different areas linked together through direct cortico-cortical connections, sends information to the striatum; the striato-thalamic system acts as a tunable filter of this lexico-semantic input; and the thalamus projects back to the lexico-semantic system, amplifying the targeted response and inhibiting its competitors.