Disorders of spatial orientation

Publisher Summary This chapter presents a study on disorders of spatial orientation. Orienting in space requires not only visual spatial abilities, for example visual localization, but also spatial cognition, and spatial attention. A further spatial capacity is to use incoming or stored visuo-spatial information for construction. Disorders of visual spatial localization can occur in the hemifield contralateral to the damaged hemisphere and are typically associated with defective saccadic localization accuracy. Patients with bilateral posterior brain damage and disturbance of visual localization in the entire visual field report difficulties in visually guided activities, because accurate fixating of, reaching for, and grasping of objects, as well as reading, writing, and drawing are impaired. In patients with hemianopia, the shifts are typically toward the affected hemifield and are associated with corresponding fixation behavior. In contrast, patients with left-sided visual neglect may show right-sided displacement. Patients with impaired visual spatial orientation have difficulties in orientating themselves in a scene or a stimulus array and may "get lost" in reading and picture viewing. The chapter discusses visuoconstructive abilities, balint syndrome, spatial neglect, and pusher syndrome. In the case of balint syndrome, the final feature that makes up the triad of symptoms is optic, or visuomotor, ataxia,, an inability to direct movement of an extremity using visual guidance. The discussion on principles of therapy and practical management includes active orienting to the contralesional side, limb activation and contralesional cueing, neck muscle vibration, and eye patching and prism exposure.