Ipsilesional intentional neglect and the effect of cueing

Background: Contralesional hemispatial neglect may be induced by an attenti onal deficit where patients are inattentive to or unaware of stimuli in con tralesional hemispace, an intentional deficit where patients are unable to act in or towards contralesional hemispace, or both. The deficits associate d with ipsilesional neglect have not been as well chararacterized. Because cueing may be used as a rehabilitative assistive device, we wanted to learn whether the efficacy of an attentional or intentional cue was related to t he type of bias. Methods: We studied a patient with a right frontotemporal stroke who had ipsilesional neglect by using a video apparatus that dissoci ates sensory-attentional and motor-intentional systems. We also performed a cueing experiment with primarily sensory-attentional cues (i.e., read the letter at the end of the line) and primarily motor-intentional cues (i.e., touch the end of the line). Results and Conclusions: Ipsilesional neglect w as primarily a motor-intentional deficit with a motor-action bias to the le ft and a secondary sensory-attentional bias for stimuli to the right. With cueing we found a double dissociation: the rightwards motor-intentional cue improved the primary left-sided intentional bias and the leftwards sensory -attentional cue improved the secondary right-sided attentional bias. Effec tive rehabilitation strategies need to address both sensory-attentional and motor-intentional deficits in patients with neglect.