Non-verbal and verbal fluency in prodromal Huntington’s disease

• Background: This study examines nonverbal (design) and verbal (phonemic and semantic) fluency in prodromal Huntington’s disease (HD). An accumulating body of research indicates subtle deficits in cognitive functioning among prodromal mutation carriers for HD. Methods: Performance was compared between 32 mutation carriers and 38 noncarriers in order to examine the magnitude of impairment across fluency tasks. The Predicted Years To Onset (PYTO) in mutation carriers was calculated by a regression equation and used to divide the group according to whether onset was predicted less than 12.75 years (HD+CLOSE; n=16) or greater than 12.75 years (HD+DISTANT; n=16). Results: The results indicate that both nonverbal and verbal fluency are sensitive to subtle impairment in prodromal HD. HD+CLOSE group produced fewer items in all assessed fluency tasks compared to noncarriers. HD+DISTANT produced fewer drawings than noncarriers in the nonverbal task. PYTO correlated significantly with all measures of nonverbal and verbal fluency. Conclusion: The pattern of results indicates that subtle cognitive deficits exist in prodromal HD, and that less structured tasks with high executive demands are the most sensitive in detecting divergence from the normal range of functioning. These selective impairments can be attributed to the early involvement of frontostriatal circuitry and frontal lobes.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Annan medicin och hälsovetenskap -- Gerontologi, medicinsk/hälsovetenskaplig inriktning (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Other Medical and Health Sciences -- Gerontology, specialising in Medical and Health Sciences (hsv//eng)

Nyckelord

Prodromal

cognition

neuropsychology

nonverbal fluency

phonemic fluency

semantic fluency

executive functioning

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)