Spatio‐temporal selectivity of loss of colour and luminance contrast sensitivity with multiple sclerosis and optic neuritis

Abstract

Colour and luminance-contrast thresholds were measured in the presence of dynamic Random Luminance-contrast Masking (RLM) in individuals who had had past diagnoses of optic neuritis (ON) some of whom have progressed to a diagnosis of multiple sclerosis (MS). To explore the spatio-temporal selectivity of chromatic and luminance losses in MS/ON, thresholds were measured using three different sizes and modulation rates of the RLM displays: small checks modulating slowly, medium-sized checks with moderate modulation and large checks modulating rapidly. The colour of the chromatic stimuli used were specified in a cone-excitation space to measure relative impairments in red-green and blue-yellow chromatic channels. These observers showed chromatic thresholds along the L/(L+M) axis that were higher than those along the S-cone axis for all display sizes/modulation rates and both red-green and blue-yellow colour thresholds were higher than luminance-contrast thresholds. The principal change in thresholds with spatio-temporal changes in the display was a reduction in thresholds for L/(L+M) and S-cones with increasing check size and modulation rate. However, luminance contrast thresholds did not change with display size/rate. These results are consistent with MS/ON selectively affecting processing in colour pathways rather than in the magnocellular pathway, and that within the colour pathways neurones with opposed L- and M-cone inputs are more damaged than colour-opponent neurons with input from S-cones.

Contrast sensitivity, first-order motion and Initial ocular following in demyelinating optic neuropathy

“…1E and F), suggesting preservation of the magnocellular visual function. This interpretation -that the affected eye of our patient showed a deficit of parvocellular pathway function, with relative sparing of magnocellular pathway function -is in agreement with some prior studies [12,29,34].…”

Spatio-temporal Contrast Sensitivity in the Cardinal Directions of the Colour Space. A Review

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] (Burr D, et al IOVS 2003;44: ARVO E-Abstract 3193). It has been shown, however, that the usefulness of these functions is rather limited in practice, for several reasons.…”

The Visual (dis)Function in Neurological Diseases

“…Color vision impairment has been observed in subjects with no history of optic neuritis and tends to be more impaired than luminance sensitivity [129][130][131][132]. A number of investigators have attempted to determine if there is a selective effect on red-green or blue-yellow mechanisms in optic neuritis.…”