title: The role of right temporal lobe structures in off-line action: evidence from lesion-behavior mapping in stroke patients.
abstract: Recent evidence suggests the possibility that not all action modes depend on dorsal visual stream processing but that off-line nontarget-directed actions, such as antipointing, require additional and even distinct neural networks when compared with target-directed online actions. Here, we explored this potential dissociation in a group of 11 patients with left visual neglect, a syndrome characterized by a loss of awareness of the contralesional side of space. Ten healthy participants and 10 right hemisphere-damaged patients without neglect served as controls. Participants had to point either directly toward targets presented on their left or right (i.e., propointing) or to the mirror position in the opposite hemispace (i.e., antipointing). Compared with both control groups, neglect patients showed reduced accuracy when antipointing but not propointing. Lesion-behavior mapping revealed that the areas critically associated with these deficits were located in the middle and superior temporal and parahippocampal gyri. We argue that neglect patients present specific deficits only when the visuomotor task taps into more perceptual representations thought to rely on ventral visual stream processing and that our results indicate that right temporal brain regions are implicated in these off-line actions.
authors.affiliation: Centre for Brain and Mind, Department of Psychology, University of Western Ontario, London W6 8RP, Canada.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Rossit
authors.forename: Paresh
authors.initials: P
authors.lastname: Malhotra
authors.forename: Keith
authors.initials: K
authors.lastname: Muir
authors.forename: Ian
authors.initials: I
authors.lastname: Reeves
authors.forename: George
authors.initials: G
authors.lastname: Duncan
authors.forename: Monika
authors.initials: M
authors.lastname: Harvey
mesh_terms: D000368:Aged; D001931:Brain Mapping; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D010468:Perceptual Disorders / Q000503:physiopathology*; D011597:Psychomotor Performance / Q000502:physiology*; D020521:Stroke / Q000503:physiopathology*; D013702:Temporal Lobe / Q000503:physiopathology*; D014796:Visual Perception / Q000502:physiology