Phonological and semantic verbal fluency test: Scoring criteria and normative data for clustering and switching strategies for Colombian children and adolescents.

BACKGROUND: Verbal fluency tests (VFT) are highly sensitive to cognitive deficits. Usually, the score on VFT is based on the number of correct words produced, yet it alone gives little information regarding underlying test performance. The implementation of different strategies (cluster and switching) to perform efficiently during the tasks provide more valuable information. However, normative data for clustering and switching strategies are scarce. Moreover, scoring criteria adapted to Colombian Spanish are missing. AIMS: (1) To describe the Colombian adaptation of the scoring system guidelines for clustering and switching strategies in VFT; (2) to determine its reliability; and (3) to provide normative data for Colombian children and adolescents aged 6-17 years. METHODS & PROCEDURES: A total of 691 children and adolescents from Colombia completed phonological (/f/, /a/, /s/, /m/, /r/ and /p/) and semantic (animals and fruits) VFT, and five scores were calculated: total score (TS), number of clusters (NC), cluster size (CS), mean cluster size (MCS) and number of switches (NS). The intraclass correlation coefficient was used for interrater reliability. Hierarchical multiple regressions were conducted to investigate which strategies were associated with VFT TS. Multiple regressions were conducted for each strategy, including as predictors age, age2 , sex, mean parents' education (MPE), MPE2 and type of school, to generate normative data. OUTCOMES & RESULTS: Reliability indexes were excellent. Age was associated with VFT TS, but weakly compared with strategies. For both VFT TS, NS was the strongest variable, followed by CS and NC. Regarding norms, age was the strongest predictor for all measures, while age2 was relevant for NC (/f/ phoneme) and NS (/m/ phoneme). Participants with higher MPE obtained more NC, and NS, and larger CS in several phonemes and categories. Children and adolescents from private school generated more NC, NS and larger CS in /s/ phoneme. CONCLUSIONS & IMPLICATIONS: This study provides new scoring guidelines and normative data for clustering and switching strategies for Colombian children and adolescents between 6 and 17 years old. Clinical neuropsychologists should include these measures as part of their everyday practice. WHAT THIS PAPER ADDS: What is already known on the subject VFT are widely used within the paediatric population due to its sensitivity to brain injury. Its score is based on the number of correct words produced; however, TS alone gives little information regarding underlying test performance. Several normative data for VFT TS in the paediatric population exist, but normative data for clustering and switching strategies are scarce. What this paper adds to existing knowledge The present study is the first to describe the Colombian adaptation of the scoring guidelines for clustering and switching strategies, and provided normative data for these strategies for children and adolescents between 6 and 17 years old. What are the potential or actual clinical implications of this work? Knowing VFT's performance, including strategy development and use in healthy children and adolescents, may be useful for clinical settings. We encourage clinicians to include not only TS, but also a careful analysis of strategies that may be more informative of the underlying cognitive processes failure than TS.

Tres tareas para la exploración de la fluidez verbal: evidencias de su fiabilidad test-retest en adultos argentinos / Three tasks for the exploration of verbal fluency: evidence of test-retest reliability in Argentine adults

Introducción: Las tareas de fluidez fonológica y semántica son de uso frecuente en la evaluación neuropsicológica por su fácil aplicación y buena sensibilidad al deterioro cognitivo. En Argentina es limitado el cuerpo de evidencia psicométrica para dichas tareas, con especial desconocimiento de la estabilidad temporal de sus medidas. La producción psicométrica es aún menor para la variante fluidez de acción (emisión de verbos en infinitivo en un minuto). En efecto, este estudio analiza la fiabilidad test-retest de tres tareas de fluidez en adultos argentinos. Sujetos y métodos: La muestra se compuso de 85 argentinos (medida de edad, 63,7) de población general no clínica, un 75,3% mujeres, de nivel de instrucción medio-alto. Se efectuó un diseño longitudinal-prospectivo administrando tareas de fluidez fonológica, semántica y de acción en dos momentos distintos con un intervalo hasta de cuatro meses. Se analizó el coeficiente de correlación intraclase (CCI), método estadístico sugerido para estudios de fiabilidad test-retest. Para interpretar el CCI se adoptaron los criterios de Fleiss. Resultados: Las tareas de fluidez fonológica y semántica demostraron buena fiabilidad, con un CCI de 0,77 y 0,79. La fluidez de acción obtuvo excelente fiabilidad, con un CCI de 0,9. Conclusión: Las tareas de fluidez relevadas poseen apropiada estabilidad temporal, por lo que se sugiere su uso en investigaciones neuropsicológicas prospectivas (cuando se evalúe el lenguaje en distintos momentos) o cuando se requiera un seguimiento de la evolución de pacientes afásicos en neurorrehabilitación. Basándose en su excelente fiabilidad, se recomienda utilizar con más frecuencia la variante de acción.(AU)

Introduction: The phonological and semantic verbal fluency tasks are frequently used in neuropsychological assessment due to their easy application and good sensitivity to dementia. In Argentina, the psychometric evidence for these tasks is limited, with a special lack of knowledge of the temporal stability of its measurements. The psychometric production is even lower for the action fluency variant (emission of verbs in the infinitive in one minute). In effect, this research analyzes the test-retest reliability of three verbal fluency tasks in Argentine adults. Subjects and methods: The sample was made up of 85 Argentine (average age, 63.7 years), 75,3% women and with a medium-high educational level. A prospective longitudinal design was carried out, administering phonological, semantic and action fluency tasks at two different times with an interval of up to four months. The intraclass correlation coefficient (ICC), a statistical method suggested for test-retest reliability studies, was analyzed. For the interpretation of the ICC, the Fleiss criteria were adopted. Results: The phonological and semantic fluency tasks showed good reliability, with ICCs of 0.77 and 0.79. The fluidity of action variant yielded ICC of 0.90, indicating excellent reliability. Conclusions: All fluency tasks have appropriate temporal stability, and their use is recommended when prospective neuropsychological research is planned (with language evaluation at di fferent times) or as a method of monitoring the evolution of aphasic patients undergoing neurorehabilitation. Based on its excellent reliability, it is recommended to use the action variant more frequently.(AU)

The impact of executive dysfunctions on Theory of Mind abilities in Parkinson's disease.

Theory of Mind (ToM) is the ability to infer and reason about others' mental states, a process impaired by Parkinson's disease (PD). ToM performance in PD seems to be strongly related to executive functioning but the exact nature of this relationship is still unclear. We aim to investigate the direct impact of several executive dysfunctions on ToM deficits (Affective and Cognitive ToM) in PD patients. Sixty-eight PD patients underwent neuropsychological tests evaluating executive control such as inhibition, cognitive flexibility, processing speed or working memory and Cognitive and Affective ToM. We divided participants into two groups based on their performance on executive tests: PD patients with poor executive functioning (PD-EF-) and those with preserved executive functioning (PD-EF+). To explore the direct impact of executive subdomains on ToM abilities, two mediation models were executed in the whole sample. We found that PD patients with poor executive functioning reported poorer scores on Affective and Cognitive ToM tasks than PD patients with preserved executive functions, controlling for age and education. Moreover, parallel mediation models, conducted in the whole sample, indicated that performance on phonological fluency mediated the relationships between educational level and both Affective and Cognitive ToM, controlling the effect of other executive tests. These findings further support the idea that executive functions are crucial in ToM processes. Particularly, phonological fluency, whose execution requires both verbal abilities and cognitive flexibility, mediated ToM performance controlling the effect of other executive functions. The identification of neuropsychological processes underpinning ToM abilities might represent a plausible target for cognitive training to strengthen ToM abilities in PD.

Características fonológicas en población escolar con dislexia: Un modelo de ecuaciones estructurales / Phonological features in a school population with dyslexia: A structural equation model

Resumen Introducción: El trastorno específico del aprendizaje es una entidad nosológica del neurodesarrollo, las manifestaciones clínicas se hacen evidentes en la etapa escolar y son persistentes en el transcurso de la vida. La dislexia (DS) se caracteriza por una afectación en la comprensión y fluidez del proceso lector, asociada a déficits neurocognitivos. Objetivo: Analizar. la relación existente entre fluidez fonológica, repetición, denominación y comprensión verbal en niños con diagnóstico de DS. Método: Se empleó una muestra de N=114 personas con diagnóstico de DS escolarizados, en edades entre 7 y 16 años y un. muestreo no probabilístico. Construimos un modelo de ecuaciones estructurales (MEE) en el software RCran 4.0.4, para analizar la relación entre las variables latentes (fluidez fonológica, fluidez semántica, repetición de pseudopalabras, repetición de frases, denominación y comprensión verbal), a través de los resultados de pruebas psicométricas estandarizadas; Test de Fluencia Verbal, Test de Boston, Evaluación Neuropsicológica Infantil y Escala Weschler IV de Inteligencia. Resultados: Las covarianzas entre fluidez fonológica y todos los componentes del lenguaje (LG) fueron positivas; fluidez semántica (σxy=0,55), repetición de pseudopalabras (σxz=0,53), repetición de frases (σxw=0,64), denominación del LG (σxv=0,60), comprensión verbal (σxy=0,57), lo que indica una relación directa. En las personas con DS, a menor fluidez fonológica mayores deficiencias del LG. Conclusión: En la DS la fluidez fonológica y semántica es limitada y se relaciona de manera directa con las manifestaciones clínicas de este trastorno del neurodesarrollo (TN).

Abstract Introduction: The specific learning disorder is a nosological entity of neurodevelopment, the clinical manifestations become evident in the school stage and are persistent throughout life. Dyslexia (DS) is characterized by an impairment in the comprehension and fluency of the reading process, associated with neurocognitive deficits. Objective: To analyze the relationship between phonological fluency, repetition, naming and verbal comprehension in children diagnosed with dyslexia (DS). Method: A sample of (N=114) school patients with DS diagnosis between the ages of 7 and 16 years, selected by non-probability sampling, was used. We built a structural equation model (MEE) in RCran 4.0.4 software, to analyze the relationship between the latent variables (phonological fluency, semantic fluency, pseudoword repetition, sentence repetition, naming and verbal comprehension), through the results of standardized psychometric tests; Verbal Fluency Test, Boston Test, Child Neuropsychological Assessment and Weschler Intelligence Scale IV. Results: Covariances between phonological fluency and all language (LG) components were positive; semantic fluency (σxy=0.55), pseudoword repetition (σxz=0.53), sentence repetition (σxw=0.64), LG naming (σxv=0.60), verbal comprehension (σxy=0.57), indicating a direct relationship. In people with DS, the lower the phonological fluency the greater the language deficits. Conclusion: In DS, phonological and semantic fluency is limited and is directly related to the clinical manifestations of this neurodevelopmental disorder (TN).

Verbal fluency in school-aged Spanish children: analysis of clustering and switching organizational strategies, employing different semantic categories and letters / Fluidez verbal en niños españoles en edad escolar: análisis de las estrategias organizativas de agrupación y cambio, empleando diferentes categorías semánticas y letras

The verbal fluency task is a measure of cognitive flexibility and search strategy within the lexicon and semantic topic. The use of organizational strategies was tested in healthy Spanish children divided in two groups: group 1 of younger children and group 2 of older children introducing different letters and semantic categories. Semantic fluency was greater than phonological fluency in both age groups. In addition, older children showed better performance of both fluencies than younger children. From the phonological analyses, younger children evoked more word with the PMR letter group than with the FAS one. Moreover, an improvement of semantic fluency associated with the animal's category faced to meals and drink was observed only in the younger children group. In respect to organizational strategies, older children used more switches specifically in FAS group and more clusters for the meals or drinks category compared with the older children group. The relationships between the number of words evoked and the number of clusters and switches for both VF tasks were significant and positive. These data suggest that the type of letter and the semantic category employed in the VF evaluation modulate the verbal fluency performance in both groups of age.

La tarea de fluidez verbal es una medida de flexibilidad cognitiva y estrategia de búsqueda dentro del contenido léxico y semántico. Se evaluó el uso de estrategias organizativas en niños españoles sanos divididos en dos grupos: grupo 1 de niños más pequeños y grupo 2 de niños mayores introduciendo diferentes letras y categorías semánticas. La fluidez semántica fue mayor que la fluidez fonológica en ambos grupos de edad. Además, los niños mayores mostraron un mejor rendimiento de ambas fluencias que los niños más pequeños. A partir de los análisis fonológicos, los niños más pequeños evocaron más palabras con el grupo de letras PMR que con el de FAS. Además, se observó una mejora de la fluidez semántica asociada con la categoría animales frente a la categoría comidas y bebidas únicamente en el grupo de niños más pequeños. Con respecto a las estrategias organizativas, los niños mayores utilizaron más cambios, específicamente en el grupo FAS y más agrupamientos para la categoría de comidas o bebidas, en comparación con el grupo de niños mayores. Las relaciones entre el número de palabras evocadas y el número de agrupamientos y cambios para ambas tareas de VF fueron significativas y positivas. Estos datos sugieren que el tipo de letra y la categoría semántica empleada en la evaluación de la VF modulan el rendimiento en fluidez verbal en ambos grupos de edad.(AU)

Neural Correlates of Letter and Semantic Fluency in Primary Progressive Aphasia.

Verbal fluency (VF) is an informative cognitive task. Lesion and functional imaging studies implicate distinct cerebral areas that support letter versus semantic fluency and the understanding of neural and cognitive mechanisms underlying task performance. Most lesion studies include chronic stroke patients. People with primary progressive aphasia (PPA) provide complementary evidence for lesion-deficit associations, as different brain areas are affected in stroke versus PPA. In the present study we sought to determine imaging, clinical and demographic correlates of VF in PPA. Thirty-five patients with PPA underwent an assessment with letter and category VF tasks, evaluation of clinical features and an MRI scan for volumetric analysis. We used stepwise regression models to determine which brain areas are associated with VF performance while acknowledging the independent contribution of clinical and demographic factors. Letter fluency was predominantly associated with language severity (R2 = 38%), and correlated with the volume of the left superior temporal regions (R2 = 12%) and the right dorsolateral prefrontal area (R2 = 5%). Semantic fluency was predominantly associated with dementia severity (R2 = 47%) and correlated with the volume of the left inferior temporal gyrus (R2 = 7%). No other variables were significantly associated with performance in the two VF tasks. We concluded that, independently of disease severity, letter fluency is significantly associated with the volume of frontal and temporal areas whereas semantic fluency is associated mainly with the volume of temporal areas. Furthermore, our findings indicated that clinical severity plays a critical role in explaining VF performance in PPA, compared to the other clinical and demographic factors.

Postprandial effects of breakfast glycaemic index on cognitive performance among young, healthy adults: A crossover clinical trial.

Objective: To evaluate the postprandial effects of high and low glycaemic index (GI) breakfasts on cognitive performance in young, healthy adults.Methods: A crossover clinical trial including 40 young, healthy adults (aged 20-40 years, 50% females) recruited from primary healthcare centres in Salamanca, Spain. Verbal memory, phonological fluency, attention, and executive functions were examined 0, 60, and 120 minutes after consuming a low GI (LGI), high GI (HGI), or water breakfast. Every subject tried each breakfast variant, in a randomized order, separated by a washout period of 7 days, for a total of 3 weeks.Results: A significant interaction between the type of breakfast consumed and immediate verbal memory was identified (P<.05). We observed a trend towards better performance in verbal memory (delayed and immediate), attention, and phonological fluency following an LGI breakfast.Discussion: Cognitive performance during the postprandial phase in young, healthy adults was minimally affected by the GI of breakfast. The potential for breakfast's GI modulation to improve short- and long-term cognitive functioning requires further research.

Deficient Explicit Access to Phonological Representations Explains Phonological Fluency Difficulties in Greek Children With Dyslexia and/or Developmental Language Disorder.

It is well-established that children with dyslexia and/or Developmental Language Disorder (hereafter children with DDLD) perform poorly on phonological tasks compared to typically developing (TD) children. However, there has been some debate as to whether their phonological deficit arises directly from an impairment in phonological representations, or instead from deficient access to (intact) phonological representations. This study tested the Degraded Phonological Representations Hypothesis and the Deficient Phonological Access Hypothesis using a task that is not often used with children with DDLD, namely phonological fluency. Both hypotheses predict that children with DDLD will retrieve fewer items than their TD peers in the phonological fluency task. However, while the Degraded Phonological Representations Hypothesis predicts smaller clusters of phonologically related items in children with DDLD, the Deficient Phonological Access Hypothesis predicts that the two groups will not differ in cluster size. How phonological fluency performance related to children's language, literacy, and phonological skills was investigated. Further, the specificity of a phonological fluency deficit in children with DDLD was tested using a nonverbal (design) fluency task. Sixty-six children with DDLD aged 7-12 years and 83 TD children aged 6-12 years, all monolingual Greek speakers, were tested on three phonological fluency categories, on nonverbal IQ, language, literacy, and phonological tasks, and on a design fluency task. The DDLD group produced significantly fewer correct responses and fewer switches compared to the TD group, but the two groups showed similar clustering and average cluster size. After controlling for age, children's language, literacy, and phonological skills significantly predicted the number of correct responses produced. The two groups did not differ significantly on the number of unique designs generated in the design fluency task. Furthermore, children with DDLD showed poorer phonological fluency performance relative to their TD peers even after design fluency performance was controlled, demonstrating the specificity of their phonological fluency deficit. This study adds to the theoretical debate on the locus of the phonological deficit in dyslexia and DLD. The findings support the hypothesis that the phonological deficit in dyslexia and DLD lies in deficient explicit access to intact phonological representations.

Patrones de correlación de fluencias semánticas y fonológicas en niños en edad escolar / Correlational Patterns in Semantic and Phonological Fluency in School Aged Children

Resumen Las tareas de fluidez verbal semántica (FVS) y fluidez verbal fonológica (FVF) son medidas sensibles para detectar y diagnosticar diversas patologías tanto en la población adulta como en la infantil. Dado que las tareas de FVS y FVF permiten detectar problemas específicos de determinadas facultades lingüísticas o cognitivas, el objetivo de este trabajo es indagar las posibles relaciones existentes entre FVS y FVF en una población de niños argentinos de nivel escolar primario de 3°, 5° y 7° grado y edades comprendidas entre los 8 y 12 años. Los 86 niños participantes respondieron a una tarea de FVS en la que se evaluaron cinco categorías (animales, partes del cuerpo, medios de transportes, ropa e instrumentos musicales) y una tarea de FVF en la que respondieron a los fonemas /f/, /a/, /s/. Se realizó un análisis de correlaciones cuyo resultado muestra que existe una asociación de mediana intensidad entre ambas tareas. Además, se llevaron a cabo un análisis factorial exploratorio y uno confirmatorio, que detectaron dos factores diferenciados: un factor verbal semántico y un factor verbal fonológico. Los resultados obtenidos muestran que los procesos fonológicos y semánticos se encuentran diferenciados desde edades tempranas, aunque por su correlación es posible concluir que ambos procesos confluyen en un mismo almacén de búsqueda en la memoria verbal.

Abstract Semantic verbal fluency tasks (SVF) and phonological verbal fluency tasks (PVF) are highly sensitive measures used to detect and diagnose different pathologies in adult and child populations. The results of numerous investigations point out differential performances between these two tasks both in adults and children. Based on this evidence, we intend to identify the possible connections between SVF and PVF in a group of Argentinian children aged 8 to 12 years old who attended to 3rd, 5th and 7th school primary levels. Participants answered to a SVF task which tested five categories (animals and body parts for living things and transports, cloth and musical instruments for inanimate objects domain) and a PVF task where the phonemes /f, a, s/ were assessed. A correlations analysis was carried out. The result showed there is a mild association between both tasks. In addition, an exploratory factor analysis and a confirmatory factor analysis were conducted. Two differential factors were detected: a semantic verbal factor and a phonological verbal factor. Our results show that phonological and semantic are different processes and function separately in early development, although due to their correlation it is possible to conclude that both processes converge in the same store in verbal memory.

Fluidez verbal semántica y fonológica en una muestra de niños de Argentina / Fluência semântica e fonológica em uma amostra de crianças Argentinas / Phonological and semantic verbal fluency tasks in a sample of Argentinean children

El objetivo del presente trabajo es obtener información del patrón evolutivo de desempeño en tareas de fluidez verbal para una muestra de niños argentinos de nivel primario de 3°, 5° y 7° grado. Se evaluó a los participantes con una tarea de fluidez semántica, en la que se evaluaron las categorías de animales, frutas y verduras, y partes del cuerpo para el dominio de seres vivos, y medios de transporte, instrumentos musicales y ropa para el de objetos inanimados. Asimismo fueron evaluados con una tarea de fluidez fonológica en la que se testearon los fonemas /f/, /a/ y /s/. Los datos obtenidos dan cuenta de diferencias de rendimiento entre las tareas de fluidez con un mejor desempeño en las tareas de fluidez semántica. Asimismo, en las tareas de fluidez semántica se observa un mejor rendimiento en el dominio de seres vivos. Las diferencias obtenidas en ambas tareas se identifican al comparar los grupos según escolaridad, siendo únicamente los niños de 3° grado los que, con menor cantidad de ejemplares recuperados, se disocian significativamente de los de 5° y 7° grado. Estos hallazgos son discutidos a la luz de posibles diferencias en función del desarrollo cognitivo, de las funciones ejecutivas y del sistema semántico.

No presente trabalho oferecemos dados de tarefas de fluência verbal para crianças argentinas de 3°, 5° e 7 ° ano do ensino fundamental. Os participantes foram avaliados com uma tarefa de fluência semântica, que testou as categorias de animais, frutas e legumes e partes do corpo para o domínio dos seres vivos e meios de transporte, instrumentos musicais e roupas para os objetos inanimados. As crianças também foram avaliadas com uma tarefa de fluência fonológica que testou os fonemas /f/, /a/ e /s/. Os dados obtidos apontam para diferenças de desempenho entre as tarefas e mostraram um melhor desempenho nas de fluência semântica. Além disso, nas tarefas de fluência semântica os participantes tiveram um melhor desempenho no domínio dos seres vivos. Tanto para fluência semântica quanto fonológica, as diferenças estiveram presentes quando os grupos foram comparados pelo nível de escolaridade, de modo que os alunos de 3° ano se dissociam significativamente dos 5° e 7 ° anos, produzindo menor quantidade de exemplares. Os resultados são discutidos à luz de possíveis diferenças originadas no desenvolvimento cognitivo, as funções executivas e o sistema semântico.

The aim of this work is to obtain data about the evolutionary pattern of performance in verbal fluency tasks for a sample of Argentinean primary school aged children (3rd, 5th y 7th grade) in semantic and phonological verbal fluency tasks. For the semantic fluency task, children were assessed in different categories: animals, fruits and vegetables, and body parts for living things domain, and means of transport, musical instruments and clothes for inanimate objects. For the phonological fluency assessment, children were tested with /f/, /a/and /s/phonemes. Both fluency tasks showed differences between grades, indicating the influence of education. Besides, irrespective of the grade, children performed better on the semantic fluency tasks. Results in the semantic fluency task also showed a better performance for the living things domain over the inanimate objects domain. Further analysis on the results showed that 3rd grade children have the worst performance, compared to 5th and 7th grade children. The results of our work are discussed taking in account cognitive mechanisms, executive functions and semantic memory development.

Structural connectivity subserving verbal fluency revealed by lesion-behavior mapping in stroke patients.

Tests of verbal fluency have been widely used to assess the cognitive functioning of persons, and are typically classified into two categories (semantic and phonological fluency). While widely-distributed divergent and convergent brain regions have been found to be involved in semantic and phonological fluency, the anatomical connectivity underlying the fluency is not well understood. The present study aims to construct a comprehensive white-matter network associated with semantic and phonological fluency by investigating the relationship between the integrity of 22 major tracts in the whole brain and semantic fluency (measured by 3 cues) and phonological fluency (measured by 2 cues) in a group of 51 stroke patients. We found five left-lateralized tracts including the anterior thalamic radiation (ATR), inferior fronto-occipital fasciculus (IFOF), uncinate fasciculus (UF), superior longitudinal fasciculus (SLF) and frontal aslant tract (FAT) were significantly correlated with the scores of both semantic and phonological fluencies. These effects persisted even when we ruled out the influence of potential confounding factors (e.g., total lesion volume). Moreover, the damage to the first three tracts caused additional impairments in the semantic compared to the phonological fluency. These findings reveal the white-matter neuroanatomical connectivity underlying semantic and phonological fluency, and deepen the understanding of the neural network of verbal fluency.

Word recognition in Alzheimer's disease: Effects of semantic degeneration.

Impairments of word recognition in Alzheimer's disease (AD) have been less widely investigated than impairments affecting word retrieval and production. In particular, we know little about what makes individual words easier or harder for patients with AD to recognize. We used a lexical selection task in which participants were shown sets of four items, each set consisting of one word and three non-words. The task was simply to point to the word on each trial. Forty patients with mild-to-moderate AD were significantly impaired on this task relative to matched controls who made very few errors. The number of patients with AD able to recognize each word correctly was predicted by the frequency, age of acquisition, and imageability of the words, but not by their length or number of orthographic neighbours. Patient Mini-Mental State Examination and phonological fluency scores also predicted the number of words recognized. We propose that progressive degradation of central semantic representations in AD differentially affects the ability to recognize low-imageability, low-frequency, late-acquired words, with the same factors affecting word recognition as affecting word retrieval.

Examining the contribution of motor movement and language dominance to increased left lateralization during sign generation in native signers.

The neural systems supporting speech and sign processing are very similar, although not identical. In a previous fTCD study of hearing native signers (Gutierrez-Sigut, Daws, et al., 2015) we found stronger left lateralization for sign than speech. Given that this increased lateralization could not be explained by hand movement alone, the contribution of motor movement versus 'linguistic' processes to the strength of hemispheric lateralization during sign production remains unclear. Here we directly contrast lateralization strength of covert versus overt signing during phonological and semantic fluency tasks. To address the possibility that hearing native signers' elevated lateralization indices (LIs) were due to performing a task in their less dominant language, here we test deaf native signers, whose dominant language is British Sign Language (BSL). Signers were more strongly left lateralized for overt than covert sign generation. However, the strength of lateralization was not correlated with the amount of time producing movements of the right hand. Comparisons with previous data from hearing native English speakers suggest stronger laterality indices for sign than speech in both covert and overt tasks. This increased left lateralization may be driven by specific properties of sign production such as the increased use of self-monitoring mechanisms or the nature of phonological encoding of signs.

Language lateralization of hearing native signers: A functional transcranial Doppler sonography (fTCD) study of speech and sign production.

Neuroimaging studies suggest greater involvement of the left parietal lobe in sign language compared to speech production. This stronger activation might be linked to the specific demands of sign encoding and proprioceptive monitoring. In Experiment 1 we investigate hemispheric lateralization during sign and speech generation in hearing native users of English and British Sign Language (BSL). Participants exhibited stronger lateralization during BSL than English production. In Experiment 2 we investigated whether this increased lateralization index could be due exclusively to the higher motoric demands of sign production. Sign naïve participants performed a phonological fluency task in English and a non-sign repetition task. Participants were left lateralized in the phonological fluency task but there was no consistent pattern of lateralization for the non-sign repetition in these hearing non-signers. The current data demonstrate stronger left hemisphere lateralization for producing signs than speech, which was not primarily driven by motoric articulatory demands.

The Name-Pronunciation Effect: Further Evidence from Chinese.

This study examined the Chinese name-pronunciation effect. The easy-to-pronounce and difficult-to-pronounce Chinese names were created using the same characters in order to control for visual perceptual and conceptual fluency. In Experiment 1, participants rated each name in terms of liking, electability as a state leader, income level, and baby name preference. An additional rating of prevalence was used to estimate familiarity. In Experiment 2, participants did not read the name aloud before rating and performed intentional recall and recognition tests. In both experiments, the easy-to-pronounce names were rated higher than difficult-to-pronounce names on liking. This effect generalized to judgments of electability and baby name preference but not to prevalence and income level. There were no differences in memory performances between the two types of names. Results are discussed in terms of the boundary condition of the name-pronunciation effect and the advantage of using Chinese names to study this effect.

Creativity and positive symptoms in schizophrenia revisited: Structural connectivity analysis with diffusion tensor imaging.

Both creativity and schizotypy are suggested to be manifestations of the hyperactivation of unusual or remote concepts/words. However, the results of studies on creativity in schizophrenia are diverse, possibly due to the multifaceted aspects of creativity and difficulties of differentiating adaptive creativity from pathological schizotypy/positive symptoms. To date, there have been no detailed studies comprehensively investigating creativity, positive symptoms including delusions, and their neural bases in schizophrenia. In this study, we investigated 43 schizophrenia and 36 healthy participants using diffusion tensor imaging. We used idea, design, and verbal (semantic and phonological) fluency tests as creativity scores and Peters Delusions Inventory as delusion scores. Subsequently, we investigated group differences in every psychological score, correlations between fluency and delusions, and relationships between these scores and white matter integrity using tract-based spatial statistics (TBSS). In schizophrenia, idea and verbal fluency were significantly lower in general, and delusion score was higher than in healthy controls, whereas there were no group differences in design fluency. We also found positive correlation between phonological fluency and delusions in schizophrenia. By correlation analyses using TBSS, we found that the anterior part of corpus callosum was the substantially overlapped area, negatively correlated with both phonological fluency and delusion severity. Our results suggest that the anterior interhemispheric dysconnectivity might be associated with executive dysfunction, and disinhibited automatic spreading activation in the semantic network was manifested as uncontrollable phonological fluency or delusions. This dysconnectivity could be one possible neural basis that differentiates pathological positive symptoms from adaptive creativity.

Investigating language lateralization during phonological and semantic fluency tasks using functional transcranial Doppler sonography.

Although there is consensus that the left hemisphere plays a critical role in language processing, some questions remain. Here we examine the influence of overt versus covert speech production on lateralization, the relationship between lateralization and behavioural measures of language performance and the strength of lateralization across the subcomponents of language. The present study used functional transcranial Doppler sonography (fTCD) to investigate lateralization of phonological and semantic fluency during both overt and covert word generation in right-handed adults. The laterality index (LI) was left lateralized in all conditions, and there was no difference in the strength of LI between overt and covert speech. This supports the validity of using overt speech in fTCD studies, another benefit of which is a reliable measure of speech production.

Recall strategies for the verbal fluency test in patients with multiple sclerosis.

UNLABELLED: Multiple sclerosis (MS) is a neurodegenerative disease characterised by inflammation and demyelination. It generates irreversible myelin changes, which in turn give rise to physical and cognitive disorders. The verbal fluency test (VF) has been shown to be a sensitive tool for detecting cognitive impairment in these patients. OBJECTIVE: To compare quantitative and qualitative aspects of performance on semantic and phonological fluency tests between MS patients and healthy controls by analysing total words produced and strategies used (clusters and switching). METHOD: We evaluated 46 patients with MS and 33 healthy controls using the VF test. RESULTS: The semantic VF task revealed no significant differences between groups; for the phonological task, patients demonstrated reduced word production (F [77]=2.286 P<.001) and poorer use of grouping strategies, resulting in more frequent switching (F [77]=3.808 P<.005). CONCLUSIONS: These results support using qualitative analysis for recall strategies, since the technique provides data about which components of the task are affected by brain damage. Clusters depend on the integrity of semantic memory, while switching has to do with developing effective search strategies, cognitive flexibility, and the ability to modify responses. Frontal lobe damage has been reported in MS, and this is consistent with results from the phonological VF test.