title: Right inferior longitudinal fasciculus lesions disrupt visual-emotional integration.
abstract: The mechanism by which the brain integrates visual and emotional information remains incompletely understood, and can be studied through focal lesions that selectively disrupt this process. To date, three reported cases of visual hypoemotionality, a vision-specific form of derealization, have resulted from lesions of the temporo-occipital junction. We present a fourth case of this rare phenomenon, and investigate the role of the inferior longitudinal fasciculus (ILF) in the underlying pathophysiology. A 50-year-old right-handed male was found to have a right medial temporal lobe tumor following new-onset seizures. Interstitial laser ablation of the lesion was complicated by a right temporo-parieto-occipital intraparenchymal hemorrhage. The patient subsequently experienced emotional estrangement from visual stimuli. A lesion overlap analysis was conducted to assess involvement of the ILF by this patient's lesion and those of the three previously described cases, and diffusion tensor imaging was acquired in our case to further investigate ILF disruption. All four lesions specifically overlapped with the expected trajectory of the right ILF, and diminished structural integrity of the right ILF was observed in our case. These findings implicate the ILF in visual hypoemotionality, suggesting that the ILF is critical for integrating visual information with its emotional content.
authors.affiliation: Harvard Medical School, Boston, MA 02115, USA, Department of Neurology, Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA, dlperez@partners.org.
authors.forename: David B
authors.initials: DB
authors.lastname: Fischer
authors.affiliation: Department of Neurology and Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA and Department of Psychiatry.
authors.forename: David L
authors.initials: DL
authors.lastname: Perez
authors.affiliation: Department of Neurology, and.
authors.forename: Sashank
authors.initials: S
authors.lastname: Prasad
authors.affiliation: Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Laura
authors.initials: L
authors.lastname: Rigolo
authors.affiliation: Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Lauren
authors.initials: L
authors.lastname: O'Donnell
authors.affiliation: Department of Neurology, and.
authors.forename: Diler
authors.initials: D
authors.lastname: Acar
authors.affiliation: Department of Neurology, and.
authors.forename: Mary-Ellen
authors.initials: ME
authors.lastname: Meadows
authors.affiliation: Department of Psychiatry.
authors.forename: Gaston
authors.initials: G
authors.lastname: Baslet
authors.affiliation: Department of Neurology, Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA, Department of Neurology and.
authors.forename: Aaron D
authors.initials: AD
authors.lastname: Boes
authors.affiliation: Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Alexandra J
authors.initials: AJ
authors.lastname: Golby
authors.affiliation: Department of Neurology, and.
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Dworetzky
mesh_terms: D001932:Brain Neoplasms / Q000150:complications*; D002540:Cerebral Cortex / Q000473:pathology / Q000503:physiopathology; D002543:Cerebral Hemorrhage / Q000150:complications*; D003861:Depersonalization / Q000209:etiology / Q000503:physiopathology; D056324:Diffusion Tensor Imaging; D004213:Dissociative Disorders / Q000209:etiology / Q000503:physiopathology*; D004644:Emotions / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018302:Neoplasms, Neuroepithelial / Q000150:complications*; D009434:Neural Pathways / Q000473:pathology / Q000503:physiopathology; D012640:Seizures / Q000209:etiology / Q000503:physiopathology*
keywords: derealization; dissociative disorders; emotions; visual hypoemotionality