Functional MRI mapping of brain activation during visually guided saccades and antisaccades: cortical and subcortical networks.
Antisaccade tasks require a subject to inhibit a saccade toward a briefly appearing peripheral target and instead to immediately generate a saccade to an equivalent point in the opposite hemifield. Using functional magnetic resonance imaging (fMRI), we investigated the neural networks required to inhibit reflexive saccades and to voluntarily generate saccades. The results demonstrated that saccade and antisaccade tasks often bilaterally activate frontal, parietal and supplementary eye fields, lenticular nuclei and occipital cortex. Additional activation of bilateral dorsolateral prefrontal cortices, supramarginal gyri, anterior cingulate cortices and thalamus was observed during antisaccade tasks. These results indicate that fronto-parietal and fronto-striato-thalamo-cortical circuits are involved in antisaccade tasks. The fronto-parietal circuit is thought to be related to the planning of saccadic eye movements that involve attentional control, while the fronto-striato-thalamo-cortical circuits connect to cortical region as a feedback network. We speculate that the abnormalities in spatial attention and eye movement control observed in schizophrenia stem from dysfunctions in the fronto-parietal and fronto-striato-thalamo-cortical circuits.
Department of Neuropsychiatry, Nihon University School of Medicine, 30-1 Oyaguchi-Kamimachi, Itabashi-ku, Tokyo 173-8610, Japan. matsuda.psyc@tmd.ac.jp
Tetsuya
T
Matsuda
Masato
M
Matsuura
Tatsunobu
T
Ohkubo
Hiromi
H
Ohkubo
Eisuke
E
Matsushima
Kentaro
K
Inoue
Masato
M
Taira
Takuya
T
Kojima
D000328:Adult; D001288:Attention / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000502:physiology; D004292:Dominance, Cerebral / Q000502:physiology; D017352:Echo-Planar Imaging; D005246:Feedback / Q000502:physiology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009415:Nerve Net / Q000502:physiology*; D009433:Neural Inhibition / Q000502:physiology*; D009802:Oculomotor Nerve / Q000502:physiology; D010100:Oxygen / Q000097:blood; D012018:Reflex / Q000502:physiology*; D012438:Saccades / Q000502:physiology*; D013788:Thalamus / Q000502:physiology; D014794:Visual Fields / Q000502:physiology*
D010100:Oxygen