title: The role of left inferior fronto-occipital fascicle in verbal perseveration: a brain electrostimulation mapping study.
abstract: The subcortical connectivity underlying verbal perseveration (VP) remains poorly understood. We have previously reported that intraoperative electrical stimulation of the caudate nucleus during awake surgery resulted in VP. Here, our purpose is to study the white matter pathway underlying VP using subcortical stimulation mapping in a series of patients who underwent glioma resection. Eleven patients with a left hemispheric low grade glioma were operated on while awake. Intraoperative direct electrical stimulation was used both at cortical and subcortical levels while the patients carried out motor and naming tasks during the resection. All patients experienced VP during electrical stimulation performed at the level of different subcortical locations, which corresponded in the 11 cases to different parts of the left inferior fronto-occipital fascicle. Perseveration persisted into the postoperative days, but resolved completely by three months.Our original findings provide further insight into the neuroanatomical basis of VP, by supporting the role of left inferior fronto-occipital fascicle. Such data may have both fundamental and clinical implications.
authors.affiliation: Division of Neurosurgery, Toronto Western Hospital, University of Toronto, 399 Bathurst St, Toronto, ON, M5T 2S8, Canada.
authors.forename: Osaama H
authors.initials: OH
authors.lastname: Khan
authors.forename: Guillaume
authors.initials: G
authors.lastname: Herbet
authors.forename: Sylvie
authors.initials: S
authors.lastname: Moritz-Gasser
authors.forename: Hugues
authors.initials: H
authors.lastname: Duffau
mesh_terms: D000328:Adult; D000368:Aged; D001921:Brain / Q000473:pathology / Q000503:physiopathology*; D001931:Brain Mapping; D001932:Brain Neoplasms / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D004558:Electric Stimulation; D005260:Female; D005625:Frontal Lobe / Q000473:pathology / Q000503:physiopathology; D007839:Functional Laterality; D005910:Glioma / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology; D009434:Neural Pathways / Q000473:pathology / Q000503:physiopathology; D019635:Neurosurgical Procedures / Q000009:adverse effects; D009778:Occipital Lobe / Q000473:pathology / Q000503:physiopathology; D020127:Recovery of Function; D013060:Speech / Q000502:physiology; D013064:Speech Disorders / Q000209:etiology / Q000473:pathology / Q000503:physiopathology*; D055815:Young Adult