How does the homophone meaning generation test associate with the phonemic and semantic fluency tests? A quantitative and qualitative analysis

Semantic verbal fluency impairment is detectable in patients with subjective cognitive decline

Patients with subjective cognitive decline (SCD) are at higher risk for conversion to dementia due to Alzheimer's disease (AD). Semantic verbal fluency (SVF) seems to be impaired in the early stages of AD. The goal of the present study was to identify the discriminative potential of verbal fluency (VF) in patients with SCD to show if very early signs of cognitive decline may be detected in SCD. We examined 93 normal controls (NC) and 61 participants with SCD. Each participant was administered a comprehensive neuropsychological battery. All participants underwent tests of VF: phonemic verbal fluency (PVF), letters K and P and SVF (animals and vegetables categories). In addition to the total score, two 30-second intervals, and clustering and switching indices in SVF were evaluated. SCD generated fewer words in the total score and 30- to 60-second interval in vegetables category and they performed more switches in animals category. There was no significant difference between the SCD and the NC groups in all other VF measures. Quantitative measures of SVF (a decreased number of vegetables) as well as qualitative measures were detected in SCD group and could be considered as an early neuropsychological marker of subtle cognitive impairment.

Verbal Versus Figural Fluency Tests in Currently Ill and Weight Restored Anorexia Nervosa Patients

Fluency tests allow domain-specific assessment of verbal and non-verbal executive functions (EF) comparison and also enable utilizing of both quantitative and qualitative scoring methods. Thirty-five currently ill anorexia nervosa patients (PANs), 33 weight-restored patients (WRAN) and 47 healthy controls (HCs) were administered the word fluency test and the five-point test. Results show that WRANs tended to perseverate more than HCs in the verbal-fluency test. In addition, PANs produced significantly less correct figures and perseverated more than HCs and WRANs; HCs used more strategy methods than PANs and WRANs. Additionally, a positive correlation was found in the HC group between the total number of words in the verbal phonemic test and the number of designs produced and the number of correct designs. No such correlations were found in both anorexia groups. In conclusion, there is a differentiation between verbal and non-verbal EF in PANs and WRANs, showing a deficiency in the non-verbal domain. These findings may contribute to our understanding of the cognitive nature of the disorder.

Age-related differences in word-retrieval but not in meaning generation

This study examines age-associated changes in retrieval on a picture-naming task, phonemic and semantic fluency tasks, and the Homophone Meaning Generation Test (HMGT). The sample included 152 Hebrew-speaking adults, half young (mean age 22.75) and half old (mean age 76.05). Groups differed on the picture-naming task and on both verbal fluency tasks, but not on the HMGT. Age explained a greater share of the variance than did education level on these three tests, whereas the opposite pattern of results was seen on the HMGT. We suggest that age-related word finding difficulties are attenuated when performance allows for semantic rather than phonological access.

Searching for the right word: performance on four word-retrieval tasks across childhood

Word retrieval was assessed in 207 normally developing Hebrew-speaking children aged 8-17 through four tasks: picture naming, phonemic fluency, semantic fluency, and homophone meaning generation (HMGT). Scores on all tests correlated positively and significantly with participant age. Yet, age effects and the correlation between age and test scores were weakest for the naming test and strongest for the HMGT. We discuss the nature of the word search involved in each task and suggest that the more executive demands required by a test the steeper the slope of performance increase on this test.

Verbal fluency, semantics, context and symptom complexes in schizophrenia

Lexical-semantic access and retrieval was examined in 15 adults diagnosed with schizophrenia and matched controls. This study extends the literature through the inclusion of multiple examinations of lexical-semantic production within the same patient group and through correlating performance on these tasks with various positive and negative clinical symptoms. On tasks of verbal fluency, meaning generation, sentence production using contextual information and confrontation naming, participants with schizophrenia made significantly more semantic errors on naming tasks; produced fewer meanings for homophones; produced fewer items on semantic, phonological, cued and switching fluency tasks; and produced more errors on sentence production tasks when compared to healthy controls. Significant correlations were also observed between ratings of psychomotor poverty and measures of semantic production and mental inflexibility. This study has provided additional evidence for deficits in lexical-semantic retrieval which are not due to underlying semantic store degradation, do not involve phonological based retrieval, and at the level of sentence generation appear to vary as a function of the contextual constraints provided.

Subthalamic stimulation affects homophone meaning generation in Parkinson's disease

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) in individuals with Parkinson's disease (PD) has often been associated with reduced verbal fluency performance. This study aimed to directly assess semantic switching as a function of STN stimulation in PD participants with the Homophone Meaning Generation Test (HMGT). Seventeen participants with PD who had received STN DBS completed the HMGT in on and off stimulation conditions. Twenty-one non-neurologically impaired participants acted as controls. PD participants (in both on and off stimulation conditions) generated significantly fewer meanings than control participants and consistent with the previous reports of verbal fluency impairment, PD participants produced fewer definitions in the on stimulation condition. PD participants (in both on and off stimulation conditions) also had greater difficulty generating definitions for nonhomographic homophones compared with homographic homographs. The results of this study indicate that STN stimulation exacerbates impairment in semantic switching.

Switching and clustering in verbal fluency tasks throughout childhood

An analysis of switching and clustering in fluency tasks was conducted on data from 180 Hebrew speakers aged 8-29. On the phonemic task, total output, number of switches, and number of clusters differed significantly across age groups and increased with age, whereas mean cluster size did not. On the semantic task, all measures increased with age. No differences were found between adolescents and adults on the phonemic variables, but adults provided more switches on the semantic task than did adolescents. The results suggest that the development of word retrieval might be more dependent on maturation of executive search strategies than on lexical enrichment.