title: Activation of the occipital cortex and deactivation of the default mode network during working memory in the early blind.
abstract: Although blind people heavily depend on working memory to manage daily life without visual information, it is not clear yet whether their working memory processing involves functional reorganization of the memory-related cortical network. To explore functional reorganization of the cortical network that supports various types of working memory processes in the early blind, we investigated activation differences between 2-back tasks and 0-back tasks using fMRI in 10 congenitally blind subjects and 10 sighted subjects. We used three types of stimulus sequences: words for a verbal task, pitches for a non-verbal task, and sound locations for a spatial task. When compared to the sighted, the blind showed additional activations in the occipital lobe for all types of stimulus sequences for working memory and more significant deactivation in the posterior cingulate cortex of the default mode network. The blind had increased effective connectivity from the default mode network to the left parieto-frontal network and from the occipital cortex to the right parieto-frontal network during the 2-back tasks than the 0-back tasks. These findings suggest not only cortical plasticity of the occipital cortex but also reorganization of the cortical network for the executive control of working memory.
authors.affiliation: 1Department of Radiology, Division of Nuclear Medicine and Research Institute of Radiological Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Hae-Jeong
authors.initials: HJ
authors.lastname: Park
authors.affiliation: 1Department of Radiology, Division of Nuclear Medicine and Research Institute of Radiological Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Ji-Won
authors.initials: JW
authors.lastname: Chun
authors.affiliation: 1Department of Radiology, Division of Nuclear Medicine and Research Institute of Radiological Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Bumhee
authors.initials: B
authors.lastname: Park
authors.affiliation: 1Department of Radiology, Division of Nuclear Medicine and Research Institute of Radiological Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Haeil
authors.initials: H
authors.lastname: Park
authors.affiliation: 1Department of Radiology, Division of Nuclear Medicine and Research Institute of Radiological Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Joong Il
authors.initials: JI
authors.lastname: Kim
authors.affiliation: 1Department of Radiology, Division of Nuclear Medicine and Research Institute of Radiological Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jong Doo
authors.initials: JD
authors.lastname: Lee
authors.affiliation: 1Department of Radiology, Division of Nuclear Medicine and Research Institute of Radiological Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jae-Jin
authors.initials: JJ
authors.lastname: Kim
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D001307:Auditory Perception / Q000502:physiology; D001766:Blindness / Q000473:pathology* / Q000503:physiopathology*; D001931:Brain Mapping; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008570:Memory, Short-Term / Q000502:physiology*; D016571:Neural Networks, Computer; D009483:Neuropsychological Tests; D009778:Occipital Lobe / Q000098:blood supply / Q000473:pathology*; D010100:Oxygen / Q000097:blood; D011930:Reaction Time / Q000502:physiology; D055815:Young Adult
chemical_list: D010100:Oxygen