Background and Purpose-To define the detailed spectrum of audiovestibular dysfunction in anterior inferior cerebellar artery territory infarction. Methods-Over 8.5 years, we prospectively identified 82 consecutive patients with anterior inferior cerebellar artery territory infarction diagnosed by MRI. Each patient completed a standardized audiovestibular questionnaire and underwent a neuro-otologic evaluation, including bithermal caloric tests and pure tone audiogram.

Otolith-related test abnormalities improve more rapidly than canal-related test abnormalities after vestibular neuritis. If patients have a positive head-thrust test result on follow-up, they are more likely to be dizzy.

The authors assessed comprehension of carefully matched classes of words, manipulating grammatical subcategory (noun and verb) and semantic (concrete and abstract) characteristics for participants with semantic dementia (SD) or probable Alzheimer's disease (AD). Participants selected the best of four words that matched a verbal description. Participants with AD or SD were significantly impaired with verbs compared with nouns. Moreover, participants with SD showed significantly greater difficulty with motion verbs compared to cognition verbs. The authors argue that two factors contribute to the difficulty with motion verbs for patients with SD. First, the verb semantic network is very poorly organized relative to the noun semantic network, leaving verbs more vulnerable to a progressive neurodegenerative disease. Second, visual feature knowledge is degraded in patients with SD because of the anatomic distribution of the disease in visual association cortex, causing relatively greater difficulty for concrete verbs compared to abstract verbs.

In addition to the hippocampus, the nucleus accumbens volume loss was also associated with increased risk of progression from MCI to AD. Furthermore, volume loss of subcortical grey matter structures was associated with severity of cognitive impairment.