Visuoperceptual impairment in MS patients: nature and possible neural origins

Abstract

Failures on visuoperceptual neuropsychological tasks (on neuropsychological tests of visuo-spatial perception or on tests concerning semantic properties of visual objects), may indicate focal deficits of visuoperceptual function, or could be the result of (an)other (peripheral) visual deficit(s), or be the effect of a more general cognitive decline. In multiple sclerosis (MS) patients exhibiting sufficient visual acuity and not showing severe cognitive deterioration, impairment on a comprehensive set of 31 visuoperceptual neuropsychological tasks was compared with spatial resolution deficits (SRD), temporal resolution deficits (TRD) for visual stimuli, abnormal pattern shift visual evoked potential (PSVEP) responses, and failing scores on neuropsychological tasks other than visuoperceptual tasks. Impairment on the visuoperceptual neuropsychological tasks was highly independent from the other abnormal visual and cognitive neurological impairments examined, suggesting that it mostly represented focal deficits. Only TRD in both eyes related to this impairment and this relationship was rather weak. Thus in some MS patients a slowed visual information processing may be one of the combined deficits underlying visuoperceptual neuropsychological task impairment. Given that SRD and TRD were not related to another stage of MS and reflect disturbances of a P (parvocellular channel and ventral stream projections) and M (magnocellular channel and dorsal stream projections) visual-system function respectively, demyelination of a certain M pathway may become a co-determinant of visuoperceptual neuropsychological task impairment more rapidly than damage to a certain P pathway.

Differentiation of Cognitive Deficit Profiles in Multiple Sclerosis Patients: Latent Profile Analysis

“…Previous studies on cognitive impairment in MS patients have not classified cognitively intact persons with poor visuospatial functions as a separate group; however, they also found a relationship between visuospatial functions and global cognitive functioning in MS patients [23]. When this profile was analyzed by comparing scores on other cognitive functions, these subjects were found to have better cognitive functioning in the domains of recall (immediate and delayed), attention, and verbal fluency compared to subjects classified as CD.…”

“…Within the MS group, 35.2% of all subjects were classified as CIVSI profile. Although visuospatial functions have received less consideration in the literature [3], around 25% of MS patients have been reported to have a deficit in visual perceptional functions [23]. Another important aspect of this latent profile is visuomotor integration and planning.…”

“…A study by Julian et al [26] on a large sample of children with MS showed that pronounced deficits in visuomotor planning were present even at a young age. Additionally, different aspects of visual perception can be affected in individuals with MS, such as the recognition of persons, perception of form, and visuospatial perception [23]. This calls for careful consideration when visuospatial functions in persons with MS are analyzed, as poorer functioning in this domain can be associated with the involvement of fine motor skills and executive functions.…”

Optic Neuritis: From Magnocellular to Cognitive Residual Dysfunction

“…Magnocellular deficits have been proposed to represent a behavioural correlate of demyelination in ON patients [31,32]. However, it is interesting to note that in ON patients, the deficit in processing LSF only occurs in terms of error rate and not in terms of reaction time.…”

Update on the relationships between neuropsychological dysfunction and structural MRI in multiple sclerosis

“…Research shows that impairment in these domains occurs with considerable frequency in MS [33][34][35][36], although less commonly than in the domains of processing speed and memory. For example, in an extensive battery of visuospatial tests, Vleugels and colleagues reported visuoperceptual deficits in MS patients that were relatively independent of other cognitive or visual problems [37]. The authors suggested that this pattern of visuoperceptual impairment may represent a focal deficit.…”