Central Cognitive Processing Speed Is an Early Marker of Huntington's Disease Onset

BACKGROUND: Several studies have suggested that cognitive processing speed may be useful for assessing early cognitive change in premanifest Huntington's disease (HD); however, current measures lack the ability to control for the effects of motor dysfunction commonly found in HD. The Computerized Test of Information Processing (CTiP) is a rapidly administered computerized tool that allows for the examination of central cognitive processing speed by using motor‐corrected scores to account for motor dysfunction. OBJECTIVE: To examine central cognitive processing speed as an early marker of HD onset using the CTiP. METHODS: The CTiP and other measures were administered to 102 HD gene carriers and 55 healthy adults (HA). Gene carriers included presymptomatic HD (pre‐HD; n = 33), prodromal HD (pro‐HD; ie, individuals close to disease onset; n = 23), and mild–moderate HD (HD; n = 46). RESULTS: The HD group performed significantly slower than all other groups (HA, pre‐HD, and pro‐HD) on most subtests (Ps