Word Fluency Performance Research Articles

Anodal transcranial direct current stimulation (atDCS) and functional transcranial Doppler sonography (fTCD) in healthy elderly and patients with MCI: modulation of age-related changes in word fluency and language lateralization.

Introduction: In addition to age-related changes in language, hemispheric lateralization of language functions steadily declines with age. Also, performance on word fluency tasks declines and is sensitive to the expression of dementia-related changes. The aim of this study is to evaluate the effect of anodal tDCS combined with a word fluency training on language lateralization and word fluency performance in healthy elderly subjects and in persons with mild cognitive impairment (MCI). Methods: The effect of anodal tDCS over the left inferio frontal gyrus (IFG) was measured in a group of healthy elderly up to the age of 67years (YG, Ø = 63.9 ± 3.02), a group of healthy elderly aged 68years and older (OG, Ø = 78.1, ± 4.85), and a group of patients with MCI (Ø = 81.18, ± 7.35) by comparing performance in phonological and semantic word fluency tasks before and after 3days of tDCS. Half of the experimental participants received sham stimulation. In addition, language lateralization was determined using a lateralization index (LI) measured with functional transcranial Doppler sonography (fTCD) before and after the stimulation period. Results: Anodal tDCS was associated with significantly higher scores in phonological but not semantic word fluency in both YG and OG. In MCI patients, no difference was measured between the tDCS and sham groups in either word fluency task. fTCD showed significantly increased left lateralization in all three groups after the training phase. However, this effect was independent of tDCS and the degree of lateralization could not be predicted by word fluency performance in any of the groups. Discussion: Phonological word fluency can be increased with atDCS in healthy elderly people by stimulating the IFG in a 3-day training. When cognitive decline has reached a certain stage, as is the case with MCI, this paradigm does not seem to be effective enough.

Word Fluency Test Performance in Primary Progressive Aphasia and Primary Progressive Apraxia of Speech.

Purpose This study compared performance on three-word fluency measures among individuals with primary progressive aphasia (PPA) and primary progressive apraxia of speech (PPAOS), and examined the relationship between word fluency and other measures of language and speech. Method This study included 106 adults with PPA and 30 adults with PPAOS. PPA participants were divided into three clinical subgroups: semantic (svPPA), logopenic (lvPPA), and nonfluent/agrammatic with or without apraxia of speech (nfPPA). Category fluency, letter fluency, and action/verb fluency tasks were administered to all participants. Results The four clinical groups performed abnormally on the word fluency measures, although not to a degree that represented high sensitivity to their PPA or PPAOS diagnosis. All PPA subgroups produced fewer words compared to individuals with PPAOS on all word fluency measures. Moderate correlations were found between word fluency and aphasia severity and naming performance in some of the clinical groups. Conclusions Word fluency measures are often challenging for individuals with PPA and PPAOS, but they are not of equal difficulty, with letter fluency being the most difficult. Differences among word fluency tests also vary to some degree as a function of the clinical group in question, with least impairment in PPAOS. However, the findings of this study do not support statistically significant differences in word fluency task performance among the PPA subgroups. Correlations suggest that word fluency performance in PPA is at least partly related to aphasia severity.

Word fluency performance and strategies in children with cochlear implants: age‐dependent effects?

Word fluency was examined in 73 Swedish children aged 6-9 years divided into two age groups, 6-7 and 8-9 years; 34 deaf children with cochlear implants (CI) (15 girls/19 boys) and 39 age-matched children with normal hearing (NH) (20 girls/19 boys). One purpose was to compare the ability to retrieve words in two different word fluency tasks; one phonemically based (FAS letter fluency) and one semantically based (animal fluency). A second purpose was to examine retrieval strategies in the two tasks by conducting an analysis of clustering and switching of word sequences. In general we found that age was an important factor for word fluency ability, in both the CI and the NH groups. It was also demonstrated that children with CI aged 8-9 years retrieved significantly fewer words and used less efficient strategies in the retrieval process, especially on the phonemically based task compared to children with NH of the same ages, whereas children 6-7 years performed similarly in both groups regarding number of retrieved words and use of strategies. The results are discussed with respect to factors such as age differences in performance for children with CI, especially for the phonemically based task.

Using Automatic Item Generation to Simultaneously Construct German and English Versions of a Word Fluency Test

There has been an increased interest in psychometric tests that enable the comparison of test scores across different language versions. From a psychometric point of view, this endeavor requires empirical evidence on the full score equivalence of these measures. However, this aim is often rather difficult to achieve. This is particularly true for the assessment of verbal abilities. In the present article, we will outline how automatic item generation can be used to overcome some of the problems researchers face in constructing psychometric tests that are valid in multilingual assessment settings. The feasibility of this approach is illustrated in the context of the construction and empirical evaluation of a German and English word fluency test. The results of the various studies reported in this article indicate that automatic item generation enables the generation of a sufficient amount of word fluency items exhibiting a high psychometric quality in both languages. Furthermore, the item pool constructed for both languages can be linked to each other using a common set of anchor items that are identical to each other with regard to their conceptual, linguistic, and psychometric characteristics, thereby facilitating cross-lingual comparisons of word fluency performance.

Prognosis for aphasia: Relationship between selected biographical and behavioural variables and outcome and improvement

Background: Numerous biographical and behavioural variables have been investigated for their prognostic value in aphasia. Tompkins, Jackson, and Schulz (1990) recommended ways to reconceptualise some of these variables and suggested exploration of additional variables that have been neglected.Aims: The purpose of this investigation was to examine the relationship between selected biographical and behavioural variables and initial performance, outcome, and amount of change in aphasia.Methods & Procedures: A total of 34 participants, from the first Veterans Administration Cooperative Study on Aphasia, composed the study sample. Each was evaluated with the Porch Index of Communicative Ability (PICA) and the Rating of Functional Performance (RFP) (a modification of the Functional Communication Profile) at 4 and 48 weeks post‐onset (WPO), before and after a 44‐week treatment trial. Information for 10 biographical and behavioural variables was available for each participant at 4 WPO. Spearman's correlations were employed to determine the relationship between each biographical and behavioural variable and initial performance, outcome, and amount of change on the PICA and RFP.Outcomes & Results: Performance at 4 WPO, pre‐treatment, on the PICA and RFP was significantly correlated. Similarly, performance on the PICA and RFP at 4 WPO was significantly correlated with conversational, Token Test, and word fluency performance at 4 WPO. Outcome on the PICA and the RFP at 48 WPO, post‐treatment, was significantly correlated with PICA, RFP, and word fluency performance at 4 WPO. Moreover, outcome on the PICA at 48 WPO was significantly correlated with conversational and Token Test performance at 4 WPO. Amount of change on the PICA between 4 WPO and 48 WPO was significantly negatively correlated with PICA, word fluency, Token Test, and conversational performance at 4 WPO. Amount of change on the RFP between 4 WPO and 48 WPO was significantly negatively correlated with RFP performance at 4 WPO.Conclusions: The results indicate that there are significant relationships between specific behavioural variables and initial performance, outcome, and amount of change on measures of language impairment and functional communication. Moreover, there is a difference between formulating a prognosis for outcome and amount of change in aphasia–‐individuals who attain higher outcomes do not necessarily make more improvement. However, the influence of a ceiling effect must be considered in this relationship. Finally, to determine the predictive precision of these relationships, future investigations will require a larger sample size and application of multiple regression analysis.

Evolution of phonemic word fluency performance in post-stroke aphasia

In this longitudinal study, quantitative and qualitative changes in responses of people with aphasia were examined on a phonemic fluency task. Eighteen patients were tested at 3-month intervals on the letters F-A-S while they received comprehensive, intensive treatment from 3 to 12 months post-stroke. They returned for a follow-up evaluation at an average of 10 months post-intervention. Mean group scores improved significantly from beginning to end of treatment, but declined post-intervention. Patients produced a significantly greater number and proportion of modifiers (adjectives and adverbs) between the beginning and end of treatment, with no decline afterwards, implying that they had access to a wider range of grammatical categories over time. Moreover, patients used significantly more phonemic clusters in generating word lists by the end of treatment. These gains may be attributed to the combined effects of time since onset and the linguistic and cognitive stimulation that patients received in therapy. Learning outcomes: Readers of this paper should (1) gain a better understanding of verbal fluency performance in the assessment of aphasia, (2) recognize the importance of analyzing qualitative aspects of single word production in aphasia, and (3) contribute to their clinical judgment of long term improvement in aphasia.

White Matter Lesions Impair Initiation of FAS Flow

Word fluency performance is known to rely on left frontal cortical regions and has also been shown to be affected by lesions in the white matter, which may be seen as white matter hyperintensities (WMH) on magnetic resonance imaging. However, word fluency may be divided into two independent components, initial and late performance, separated in time [J Clin Exp Neuropsychol 1998;20:137–143]. The purpose of the current study was to investigate the relationship between the two components of FAS fluency performance and WMH. Patients varying in degree of memory impairment participated: Alzheimer’s disease, mild cognitive impairment and subjective memory disorder. WMH were rated with the Scheltens scale in the periventricular and deep subcortical areas. Results demonstrated that WMH in this sample of patients may be summarized in two indices according to a principal factor analysis, one anterior factor mainly related to WMH in the frontal lobes and adjacent to ventricles, and a second posterior factor related to parietal and occipital WMH. The initial FAS performance was related to anterior WMH, in particular left frontal or lateral periventricular hyperintensities, whereas the late FAS performance was not related to any index of WMH.

Pathological association and dissociation of functional systems in multiple sclerosis and Huntington's disease

This study examined pathological associations and dissociations of functional cognitive systems in patients with multiple sclerosis and Huntington's disease. Using the subtests of the WAIS-R, two motor tests, and the word fluency test, the intertest correlations showed distinct patterns. In comparison to normals, the two clinical groups exhibited a greater degree of association among the tests. Subsequently, word fluency performance was predicted from these tests. For the normals, the overall predictive power was quite low (7%). For the MS group, the predictive power rose to 28%. For the HD group, the predictive power was 50%. These results suggest that pathological association of functional systems may be a marker of brain dysfunction and that the affected systems may be delineated by these methods.

Prediction of psychosocial recovery after head injury with cognitive tests and neurobehavioral ratings

A series of 53 patients was studied using a battery of tests and a neurobehavioral rating scale on average 4 months after closed-head injury (CHI). Social outcome was assessed 1 year after injury by interviewing a family member. The results supported the hypothesis that tests of flexibility and programming rather than tests of cognitive skills predict psychosocial recovery after CHI. Spatial Learning with Self-Set Goals and Sorting were measures of flexibility and programming. Contrary to expectation, word fluency performance was unrelated to these measures, but was associated with conventional intelligence tests, which did not predict psychosocial recovery. Cognition/Energy deficit on the Neurobehavioral Rating Scale and increased age were useful predictors of poor psychosocial outcome, whereas computed tomography findings or the Glasgow Coma Score were weakly related to the outcome indices. Evidently, cognitive flexibility and mental programming are very important psychological prerequisites of social recovery after CHI.

The effects of lateralized temporal lobe dysfunction on normal and semantic word fluency

Word fluency performance was studied in 32 patients with unilateral temporal lobe epilepsy (TLE) and 25 healthy dextral controls. Two word fluency tasks were administered conforming to either formal-based criteria or semantic-based criteria. Performance for TLE patients was assessed both pre-operatively and approximately 1 week following anterior temporal lobectomy. Both formal and semantic word fluency decreased regardless of resection laterality. Left TLE patients performed significantly worse at both pre- and post-operative assessments compared to the right TLE patients, while right TLE patients performed significantly poorer than controls on all verbal fluency criteria at pre- and post-operative assessments. In addition, both TLE and control groups produced significantly fewer formal and semantic words during the second 30-sec portion of each task. These findings are discussed in terms of temporal lobe contributions to word fluency production and lexical semantic processing.

Word fluency performance on common categories by subjects with closed head injuries

Abstract Previous research on word fluency performance in subjects with closed head injuries has used ad hoc categories such as listing words that begin with particular letters. The nature of this category type may have contributed to the poor performance of these subjects. The present study used common categories, such as fruits and furniture, which are more semantically coherent to assess word fluency performance. In addition to tallying the number of examples retrieved, the nature of the examples was examined in terms of their typicality ratings. The results indicated that the subjects with closed head injuries retrieved significantly fewer examples than did non-brain-damaged subjects. This suggests that their retrieval problems exist independent of the type of category used. Despite the difficulty in retrieving sufficient numbers of category examples, those retrieved were similar to the examples recalled by non-brain-damaged subjects in terms of typicality ratings. This suggests that closed head-injured subjects' perceptions of what category members constitute good examples is relatively intact.