Speedy eye movements in multiple sclerosis: Association with performance on visual and nonvisual cognitive tests

Objective: Eye movement difficulties in multiple sclerosis (MS) are common and may influence performance on cognitive tests. The following studies examined associations between a new measure of speedy eye movement speed and visual/nonvisual cognitive tests. Method: In Experiment 1, MS patients (N = 71) were administered cognitive tests and the Speedy Eyes Test (SET) as a measure of purposeful speedy eye movements under timed conditions. Experiment 2 was composed of MS patients (n = 60) and a neurologically healthy comparison group (n = 31) and examined group differences in an abbreviated version of the SET. Results: In both studies, slower eye movements were significantly associated with poorer performance on cognitive tests with a large effect size in Experiment 1 and a medium effect size in Experiment 2. Analyses in Experiment 2 also revealed significant group differences in an abbreviated measure of the SET, where MS patients had slower eye movements than the comparison group. Conclusions: Pending further research, the SET, a brief, inexpensive, and nontechnical measure of speedy eye movement, may serve as a visual/oculomotor indicator of cognitive impairment in multiple sclerosis.