Functional and anatomical profile of visual motion impairments in stroke patients correlate with fMRI in normal subjects

• Published in: Journal of neuropsychology Vol. 4; no. 2; pp. 121 - 145
• Main Authors: Vaina, Lucia M., Sikoglu, Elif M., Soloviev, Sergei, LeMay, Marjorie, Squatrito, Salvatore, Pandiani, Gabriella, Cowey, Alan
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.09.2010; British Psychological Society
• Subjects: Adult; Adult and adolescent clinical studies; Aged; Aged, 80 and over; Biological and medical sciences; Brain Mapping; Cerebral Cortex - blood supply; Cerebral Cortex - pathology; Discrimination (Psychology); Female; Functional Laterality - physiology; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging - methods; Male; Medical sciences; Middle Aged; Motion Perception - physiology; Neurology; Neuropsychological Tests; Organic mental disorders. Neuropsychology; Orientation - physiology; Oxygen - blood; Perceptual Disorders - etiology; Perceptual Disorders - pathology; Photic Stimulation - methods; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Psychophysics - methods; Reaction Time; Stroke - complications; Stroke - pathology; Vascular diseases and vascular malformations of the nervous system; Human; Nervous system diseases; Stroke; Stimulus movement; Vision disorder; Central nervous system; Cardiovascular disease; Nuclear magnetic resonance imaging; Cerebral disorder; Encephalon; Vascular disease; Eye disease; Visual impairment; Vision; Central nervous system disease; Perception; Cerebrovascular disease; Functional imaging
• ISSN: 1748-6645; 1748-6653
• DOI: 10.1348/174866409X471760

We used six psychophysical tasks to measure sensitivity to different types of global motion in 45 healthy adults and in 57 stroke patients who had recovered from the initial results of the stroke, but a large subset of them had enduring deficits on selective visual motion perception tasks. The patients were divided into four groups on the basis of the location of their cortical lesion: occipito‐temporal, occipito‐parietal, rostro‐dorsal parietal, or frontal‐prefrontal. The six tasks were: direction discrimination, speed discrimination, motion coherence, motion discontinuity, two‐dimensional form‐from‐motion, and motion coherence – radial. We found both qualitative and quantitative differences among the motion impairments in the four groups: patients with frontal lesions or occipito‐temporal lesions were not impaired on any task. The other two groups had substantial impairments, most severe in the group with occipito‐parietal damage. We also tested eight healthy control subjects on the same tasks while they were scanned by functional magnetic resonance imaging. The BOLD signal provoked by the different tasks correlated well with the locus of the lesions that led to impairments among the different tasks. The results highlight the advantage of using psychophysical techniques and a variety of visual tasks with neurological patients to tease apart the contribution of different cortical areas to motion processing.