title: Motor role of parietal cortex in a monkey model of hemispatial neglect.
abstract: Parietal cortex is central to spatial cognition. Lesions of parietal cortex often lead to hemispatial neglect, an impairment of choices of targets in space. It has been unclear whether parietal cortex implements target choice at the general cognitive level, or whether parietal cortex subserves the choice of targets of particular actions. To address this question, monkeys engaged in choice tasks in two distinct action contexts--eye movements and arm movements. We placed focused reversible lesions into specific parietal circuits using the GABAA receptor agonist muscimol and validated the lesion placement using MRI. We found that lesions on the lateral bank of the intraparietal sulcus [lateral intraparietal area (LIP)] specifically biased choices made using eye movements, whereas lesions on the medial bank of the intraparietal sulcus [parietal reach region (PRR)] specifically biased choices made using arm movements. This double dissociation suggests that target choice is implemented in dedicated parietal circuits in the context of specific actions. This finding emphasizes a motor role of parietal cortex in spatial choice making and contributes to our understanding of hemispatial neglect.
authors.affiliation: Department of Anatomy and Neurobiology, Washington University School of Medicine, St. Louis, MO 63110; and Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO 63130 jan@eye-hand.wustl.edu.
authors.forename: Jan
authors.identifier: http://orcid.org/0000-0003-0527-5559
authors.initials: J
authors.lastname: Kubanek
authors.affiliation: Department of Anatomy and Neurobiology, Washington University School of Medicine, St. Louis, MO 63110; and.
authors.forename: Jingfeng M
authors.identifier: http://orcid.org/0000-0001-6519-3462
authors.initials: JM
authors.lastname: Li
authors.affiliation: Department of Anatomy and Neurobiology, Washington University School of Medicine, St. Louis, MO 63110; and Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO 63130.
authors.forename: Lawrence H
authors.identifier: http://orcid.org/0000-0002-3776-0199
authors.initials: LH
authors.lastname: Snyder
mesh_terms: D000818:Animals; D002755:Choice Behavior; D004195:Disease Models, Animal; D000882:Haplorhini; D016015:Logistic Models; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D010296:Parietal Lobe / Q000503:physiopathology*; D010468:Perceptual Disorders / Q000503:physiopathology*; D012438:Saccades / Q000502:physiology; D013647:Task Performance and Analysis
keywords: LIP; attention; choice; decision; spatial cognition