The King–Devick test as a predictor of cognitive effects after chronic partial sleep restriction: a pilot study

The King–Devick test (K–D) is sensitive to the effects of acute sleep deprivation. It remains unclear whether the K–D is sensitive to the effects of chronic partial sleep restriction (SR). K–D performance was compared in a college student sample at baseline and after a week of SR. Subjects also completed measures of attention, processing speed, working memory, vocabulary and verbal reasoning. Subjects performed worse relative to their baselines on the K–D than previous test–retest reliability literature indicates, and worse on tests of attention, processing speed and working memory. Verbal reasoning and vocabulary were unaffected. An association between K–D performance and sleep duration during SR trended toward significance. These results provide initial support for the sensitivity of the K–D to SR.