A Toolkit for Analyzing Strategy Use in Phonemic Verbal Fluency Tasks preprint

The phonemic verbal fluency task is a common cognitive assessment of language and executive functioning which asks participants to list as many words as they can that begin with a given letter. Verbal fluency tasks are widely used to identify deficits in verbal fluency, which have been associated with disorders such as schizophrenia and dementia. Verbal fluency tasks are scored by the number of correct responses, however analysis of “clusters” of related words within a response list can give insights into the cognitive strategies used by participants. Unfortunately, manual word cluster analysis is time and labor intensive and inconsistent, since raters may cluster words differently depending on how they themselves have phonetically categorized the words. We present an automated pipeline for quantification of strategy use in the phonemic verbal fluency task, “LetterVF”. LetterVF is a python module (i.e., a script containing useful functions, which can be imported and used in other scripts) that uses a pronunciation dictionary to convert verbal fluency task data items into lists of phonemes, which can be analyzed to identify clusters of words that share similarities in any of several clustering categories. Additionally, LetterVF contains useful functions for identifying intrusions (words which do not follow the rules for the task), identifying perseverations (responses repeated within the same trial), counting the number of cluster switches in a list, and calculating the average size of clusters for a list. Analysis of data from 50 participants’ verbal fluency task responses indicated that analysis using LetterVF yields accuracy and consistency on par with manual analysis. Our hope is that this tool will allow researchers to get more out of their datasets, and explore new topics related to cognitive strategy use, such as how strategies change with age and differences in strategies between experimental groups.

Cognitive training with virtual reality at older people longterm residences

Purpose: to describe a series of cases of older people with a clinical diagnosis of mild cognitive impairment or dementia at elderly long-term residences using virtual reality as cognitive rehabilitation.Methods: this study is a series of cases. Older adults diagnosed with mild cognitive impairment or dementia were included. Elderly people with visual and/or hearing problems that made it impossible to carry out the training were excluded. The same tests were used after intervention and at follow up after 15 days.Results: final sample consisted of 13 women and the mean age was 81.77 years (± 6.94). Patients were divided into 2 groups: mild cognitive impairment group and the dementia group. According to the therapeutic objectives aimed at improving fluency, among the results, the improvement in the scores to the group mild cognitive impairment stands out for the phonemic verbal fluency tests 23.63 (± 12.72) pre-test and 29.50 (± 11.14) post-test. There was an improvement in mild cognitive impairment group scores for the phonemic verbal fluency tests 23.63 (± 12.72) pretest and 29.50 (± 11.14) post-test. In the dementia group, test scores were 10 (± 5, 47) pretest and 12.80 (± 5.72) post-test. On the semantic verbal fluency test, the mild cognitive impairment group showed improvement 11.00 (± 3.62) pretest and 13.88 (± 6.03) post-test, while the dementia group test scores were 7.60 (± 4.56) pretest and 8.20 (± 5.12) post-test.Conclusion: regarding phonemic verbal fluency, virtual reality may be a good resource for improving the performance of older adults with mild cognitive impairment. Results were not maintained in the medium term, showing the importance of continual training.

Characteristics of Clustering and Switching in Verbal Fluency according to Healthy Elderly Group

Objectives: The purpose of this study was to investigate the characteristics of clusters and switches through verbal fluency tasks by different age groups among the elderly.Methods: Ninety-four healthy elderly adults participated in this study. The verbal fluency task consisted of semantic verbal fluency and phonemic verbal fluency. The categories of ‘animal’ and ‘supermarket’ were used for semantic fluency, and the categories ‘/k/’, ‘/o/’ and ‘/s/’ were used for phonemic fluency.Results: First, there was a significant difference between the age groups. The number of correct responses in the verbal fluency task decreased as age increased. Second, the mean cluster size for verbal fluency did not show a significant difference among groups in tasks of semantic and phonemic verbal fluency. Third, the number of switches showed a significant difference between groups in semantic and phonemic verbal fluency. In the post-analysis results of semantic fluency, a significant difference was found in the category of ‘animals’ between the young-old and old-old age group, and a significant difference was found in the number of switches in the category of ‘supermarket’ between the middle-old and old-old age group. Finally, the semantic fluency task showed the highest frequency of perseverative error, and the phonemic fluency task showed the highest frequency of other errors.Conclusion: These results of this study are meaningful in investigating characteristics of cluster and switch as well as the performance of correct rate through the verbal fluency tasks according to the elderly group.

Phonemic Verbal Fluency and Midbrain Atrophy in Progressive Supranuclear Palsy

Background: The neuropsychological profile of progressive supranuclear palsy (PSP) patients is mainly characterized by executive dysfunction, but the relationship between the latter and midbrain atrophy is still unclear. Objective: The aims of the study were to investigate which test evaluating executive functioning is more frequently impaired in PSP patients and to evaluate the relationship between midbrain-based MRI morphometric measures and executive dysfunction. Methods: PSP patients who had undergone a neuropsychological battery assessing executive functioning with the Frontal Assessment Battery (FAB), the phonemic verbal fluency F-A-S, the Raven’s Progressive Colored Matrix, and the Stroop word colors test (time and errors) were enrolled in the study. A group of Parkinson’s disease (PD) patients matched by age, sex, education, and global cognitive status was selected. All the enrolled patients also underwent a volumetric T1-3D brain MRI. Results: Thirty-five PSP patients and 35 PD patients were enrolled. Patients with PSP as compared to patients with PD showed a significant greater impairment in verbal fluency (16.0±7.9 and 23.4±8.7 words/180 s; p < 0.001) and a significant lower score at the FAB total score (11.5±3.8 and 13.7±3.4; p = 0.013). Midbrain area was significantly smaller in PSP patients than in PD patients (83.9±20.1 and 134.5±19.9 mm2; p < 0.001). In PSP patients, a significant positive correlation between verbal fluency and the midbrain area (r = 0.421; p = 0.028) was observed. Conclusion: Our findings suggest that the phonemic verbal fluency is among the most frequently impaired executive functions in PSP patients and is strongly correlated to midbrain atrophy.

Characteristics of Resting-State Functional Connectivity in Older Adults after the PICMOR Intervention Program: A Preliminary Report

Background: The present study aimed to provide a basis for future research examining neural mechanisms underlying the beneficial effect of an intervention program named Photo-Integrated Conversation Moderated by Robots (PICMOR) on verbal fluency in older adults, which was identified in our previous study. In this preliminary report, we conducted an additional experiment using resting-state functional magnetic resonance imaging (rsfMRI) and investigated the characteristics of resting-state functional connectivity (rsFC) of participants in the intervention group (INT) by comparing with that of participants in the control group (CONT).Methods: The rsfMRI data were acquired from 31 participants in INT and 30 participants in CONT after the randomized control trial. These data were analyzed by a seed-based approach, in which the left inferior and middle frontal gyrus (IFG/MFG) were selected as seed regions and the rsFCs with them were compared between INT and CONT. To interpret the group difference in the rsFCs, we also conducted regression analyses using individual scores of the phonemic verbal fluency test, which were collected before and after the intervention.Results: We found higher rsFC in INT than in CONT between the left IFG and the temporal pole and MFG. The rsFC strength between the left IFG and temporal pole positively correlated with an increased score in the phonemic verbal fluency test through the intervention period. In contrast, we found lower rsFC in INT than in CONT between the left MFG and the posterior cingulate cortex, precuneus, and postcentral gyrus.Conclusions: Along with our previous findings that greater enhancement of the phonemic verbal fluency score through the intervention period was observed in INT than in CONT, the present findings suggest that the beneficial intervention effect is characterized by enhanced rsFC of the left IFG with semantic and executive control-related regions and suppressed rsFC between the left MFG and default mode network.Trial registration: The trial was retrospectively registered at the UMIN Clinical Trials Registry (UMIN000036667) (Date of registration: 7th May, 2019).