The impact of oculomotor functioning on neuropsychological performance in Huntington disease

ABSTRACT

Huntington disease (HD) is a neurodegenerative condition with prominent motor (including oculomotor), cognitive, and psychiatric effects. While neuropsychological deficits are present in HD, motor impairments may impact performance on neuropsychological measures, especially those requiring a speeded response, as has been demonstrated in multiple sclerosis and schizophrenia. The current study is the first to explore associations between oculomotor functions and neuropsychological performance in HD. Participants with impaired oculomotor functioning performed worse than those with normal oculomotor functioning on cognitive tasks requiring oculomotor involvement, particularly on psychomotor speed tasks, controlling for covariates. Consideration of oculomotor dysfunction on neuropsychological performance is critical, particularly for populations with motor deficits.

KEYWORDS:

• Huntington disease
• PREDICT-HD
• oculomotor functioning
• neuropsychology
• processing speed

Acknowledgements

We thank the PREDICT-HD sites, the study participants, the National Research Roster for Huntington Disease Patients and Families, the Huntington’s Disease Society of America, and the Huntington Study Group.

Notes

¹ On the Buttons task, a touch screen computer monitor displayed a series of “buttons” arranged in 10 vertical pairs, with the pairs arranged in a line across the screen, along with additional buttons at the left and right of the rows to indicate the start and finish positions. The buttons were blue when depressed and turned white when pressed. Each participant was instructed to touch the white button in each pair as quickly and as accurately as possible. When each button was touched, a sound was produced to indicate the correct response. The participant continued to touch each illuminated white button down the sequence until the last column was depressed. The computer recorded the time for which each button was held down and the time between the release of one button and the depression of the next.

Additional information

Funding

This work was supported by the National Institutes for Health, National Institute of Neurological Disorders and Stroke [grant number 5R01NS040068] awarded to Jane Paulsen; CHDI Foundation, Inc. [grant number A6266], [grant number A2015] awarded to Jane Paulsen; and Cognitive and Functional Brain Changes in Preclinical Huntington’s Disease (HD) [grant number R01NS054893] awarded to Jane Paulsen.