Verbal Fluency Deficits Research Articles

Clustering strategies on tasks of verbal fluency in Parkinson's disease

The verbal output of patients with Parkinson's disease (PD) was analyzed for semantic and phonemic clusters on tasks of verbal fluency. One task required cued retrieval by semantic category (i.e. animals), and one required non-cued retrieval by initial letter (e.g. words beginning with ‘F’). Nondemented PD patients ( N=25) produced significantly fewer words on the cued semantic retrieval task than age-, gender- and education-matched normal control subjects ( N=22), but were not impaired on the non-cued letter retrieval task. However, overall, PD patients were able to form more semantic clusters than phonemic clusters. These results are discussed in light of other studies of verbal fluency deficits in patients with PD.

Verbal fluency deficits in female alcoholics

Verbal fluency deficits in female alcoholics (n = 48) were investigated using Thurstone's Word Fluency Test (TWFT) and a category fluency test. Overall, alcoholics performed less well than did controls (n = 36). Simple effects indicate that although controls performed less well on category fluency than on the TWFT, alcoholics did not differ between the two tests. Simple effects also show that controls' performance was superior to that of alcoholics on the category fluency test, but the groups did not differ on the TWFT. The pattern of results suggests that the process of shifting rapidly between categories is more difficult than perusing a mental lexicon. Correlations between these tasks and other tests of cognitive functioning suggest that the TWFT and the category fluency test may be assessing different types of verbal fluency.

SPECT, MRI and cognitive functions in multiple sclerosis.

Seventeen patients with relapsing remitting multiple sclerosis (MS) and mild physical disability had neuropsychological testing, magnetic resonance imaging (MRI) and single photon emission computerised tomography (SPECT) using technetium 99m (99mTc) hexamethyl-propyleneamine oxime (HMPAO). Performance in verbal fluency, naming and memory testing appeared to be impaired in MS patients compared with 17 age-sex and education matched normal controls. Weighted periventricular and confluent lesion scores and the width of the third ventricle, proved to be the most sensitive MRI measures in differentiating more cognitively impaired patients from those who were relatively unimpaired. Ratios of regional to whole brain activity, measured by SPECT, showed significant reduction in the frontal lobes and in the left temporal lobe of MS patients. A relationship was found between left temporal abnormality in 99mTc-HMPAO uptake and deficit in verbal fluency and verbal memory. Finally, asymmetrical lobar activity indicated a predominant left rather than right temporo-parietal involvement.

Retrieval from semantic and letter-initial categories in patients with Parkinson's disease

We report the impaired performance by a group of 27 patients with Parkinson's disease (vs matched controls) on semantic and letter-initial verbal fluency tasks, carried out in both single and alternating category conditions. Individual differences in fluency were significantly correlated with confrontation picture naming scores in the patient group, but not in control subjects. However, the PD patients showed no significant correlation between verbal fluency scores, and rate of reciting days of the week as rapidly as possible. Both controls and patients produced more items when retrieving words from a single category than when alternately retrieving words from two categories. The magnitude of the decrement was nonetheless no greater in the patient than in the control population. This findings shows that “task switching” per se is not impaired in PD. We suggest that the verbal fluency deficit, while it may in part be attributed to motor-speech factors, primarily reflects an underlying cognitive disorder.

The verbal selective reminding test: preliminary data for healthy elderly.

The verbal selective reminding test was administered to sixty independent living well-educated, healthy elderly, aged 65-75. All subjects met exclusion criteria which were designed to ensure that the results were not secondary to deficits in attention, verbal fluency and intellectual function. On selective reminding, the females did significantly better than the males on most dependent measures. Males and females showed a significant decrease from last trial recall to recall following a fifteen minute delay.