Semantic and Phonemic Verbal Fluency in Blinds

A person who has suffered the total loss of a sensory system has, indirectly, suffered a brain lesion. Semantic and phonologic verbal fluency are used for evaluation of executive function and language. The aim of this study is evaluation and comparison of phonemic and semantic verbal fluency in acquired blinds. We compare 137 blinds and 124 sighted people in verbal fluency task. The tasks were phonemic and semantic verbal fluency test that subjects should be generate as many word as possible in a limited amount of time for a given letter (Phonemic fluency) or a given category (Semantic fluency). Independent T Test was used to comparing blind with sighted. Findings show significant difference between two groups so that that sighted subjects have higher performance in semantic verbal fluency task (p = 0.000). Comparing sighted and blind subjects in phonemic verbal fluency task shows performance in sighted subjects (p = 0.000). Based on this study blinds have lower performance in semantic and phonemic verbal fluency task as a executive function of frontal lobe.     

Verbal fluency output in children aged 7-16 as a function of the production criterion: qualitative analysis of clustering, switching processes, and semantic network exploitation

Developmental changes in children's verbal fluency were explored in this study. One hundred and forty children aged from 7 to 16 completed four verbal fluency tasks, each with a different the production criterion (letter, sound, semantic, and free). The age differences were analyzed both in terms of number of words produced, and clustering, switching, and semantic network exploration. Analysis of the number of words produced showed a larger difference between the 7-8- and the 9-10-year-olds in semantic than in letter fluency, but this difference gradually disappeared with increasing age for semantic fluency while remaining constant for letter fluency. In letter fluency production, age modified both the number of switches and clusters formed whereas in semantic fluency tasks, only cluster size changed with age. Concerning the semantic network exploration indicators derived from the supermarket fluency task, the number of categories sampled increased from 11 to 12 years, but efficient semantic exploitation occurred only after the age of 13-14 years. These results are discussed in terms of the development of strategic retrieval components and categorical knowledge.     

Children's word fluency strategies

Two word fluency tasks, the FAS letter fluency task and the "animal" semantic fluency task, were administered to 130 healthy Swedish-speaking children between 6 and 15 years of age. The main aim was to gather normative data on these word fluency tasks for Swedish-speaking children. Another purpose was to examine the switching and clustering strategies used, along with the occurrence of erroneous responses, in relation to demographic data and number of words retrieved. Both phonological and semantic analyses of switching and clustering were conducted. Higher age was found to be related to a more effective use of phonological and semantic switching and clustering strategies. The reference data resulting from this study may be of clinical value in examinations of children with various diagnoses, including language impairment.     

Effects of Grammatical Categories on Letter Detection in Continuous Text

The present study focuses on the interplay between the linguistic principles and the psycholinguistic processes involved in reading. Results from 56 participants on a letter detection task reveal that readers do not process all function words in the same manner. Omission rates were highest for function words occupying the head of maximal projections such as complementizers and determiners. Prepositions were shown to occupy an intermediary position between content and function words, with omission rates varying depending on their semantic load. Together these results appear to bolster and offer a finer grained picture of the role of function words within the framework of both the Guidance Organization (Greenberg et al. in Psychon Bull Rev 11(3):428–433, 2004) and Attentional Disengagement (Roy-Charland et al. in Percept Psychophys 69(3):324–337, 2007) reading models. The results of the present study are discussed using an X-bar theory approach with the goal of refining the structural account of letter detection errors.     

Why do older adults have difficulty with semantic fluency?

Aging involves many cognitive declines, particularly in fluid intelligence, with relative maintenance of crystallized intelligence. This paradox is evident in the language domain: lexical retrieval becomes slower and less accurate, despite well preserved vocabularies. Verbal fluency assesses both crystallized and fluid aspects of language. Semantic fluency hypothetically reflects semantic knowledge, while letter fluency putatively reflects executive functioning, which would predict a greater impact of aging on the latter. However, the opposite is typically observed.

To investigate factors contributing to such asymmetries, we examined verbal fluency in 86 adults (30-89 years). Multiple regression analyses indicated that semantic fluency depends largely on lexical retrieval speed, as well as visualization strategies to support controlled retrieval, skills which may disproportionately decline with age. By contrast, letter fluency relies heavily on vocabulary knowledge, providing some protection against age-related declines. These findings contribute to our understanding of the mechanisms of typical age-related declines in word retrieval.     

Differential impacts of age of acquisition on letter and semantic fluency in Alzheimer's disease patients and healthy older adults

The degree to which the typical age of acquisition (AoA) of words and word frequency have separable influences on verbal production tasks has been strongly debated. To examine the overlap between these factors in verbal fluency tasks, the performance of Alzheimer's disease (AD) patients (N?=?34) and normal elderly controls (N?=?36) was compared on semantic (e.g., vegetables) and letter (e.g., words that begin with F) fluency tasks. These comparisons revealed that words generated for the semantic fluency task had an earlier AoA while words generated for the letter fluency task had a higher word frequency. Differences in AoA between AD patients and controls were larger for semantic than letter fluency. These results suggest that AoA has an effect on verbal production that is independent of word frequency and that AoA has a semantic locus.     

Verbal fluency and creativity: General and specific contributions of broad retrieval ability (Gr) factors to divergent thinking

The Cattell–Horn–Carroll (CHC) model of intelligence views creativity as a first-level factor within the second-level factor of broad retrieval ability (Gr), alongside other first-level abilities such as ideational fluency and word fluency. Traditional methods of measuring creativity, however, confound idea quality with idea quantity, which might exaggerate the relationship between creativity scores and verbal fluency factors. Participants (n = 131 adults) completed two divergent thinking tasks (unusual uses for a rope and a box), which were scored using newer methods that effectively separate creativity (scored via subjective ratings) and fluency (scored as number of responses). They then completed 16 verbal fluency tasks that assessed six lower-order Gr factors: word fluency, associational fluency, associative flexibility, ideational fluency, letter fluency, and dissociative ability. Viewed singly, many of the lower-order factors significantly predicted creative quality and fluency. General Gr had substantial effects on creative quality (standardized β = .443) and fluency (β = .339) in a higher-order model as well as in a bifactor model (quality β = .380, fluency β = .327). Moreover, general Gr was the only significant predictor in the bifactor model, suggesting that it, not the specific factors, was most important. All effects were essentially the same after controlling for typing speed and vocabulary knowledge. The findings thus support the CHC view of creativity/originality as a lower-order component of Gr, illuminate the relationships between creativity and first-level Gr factors, extend the study of creativity and intelligence beyond fluid intelligence, and further indicate that creativity is more closely tied to cognitive abilities than creativity research has yet recognized.     

Semantic priming occurs for word but not location pronunciation in the postcue task

Semantic priming refers to the finding that a word response is facilitated if it is preceded by a related word compared to when it is preceded by an unrelated word. Dallas and Merikle (Can J Psychol 30: 15–21 1976a; Bull Psychon Soc 8: 441–444 1976b) demonstrated that semantic priming occurred under conditions in which a pair of simultaneously displayed words was previewed for over a second prior to the onset of a cue indicating which of the words should be pronounced aloud (postcue task). In contrast, semantic interference effects have been reported for postcue picture-naming tasks (Dean et al. in J Exp Psychol Learn Mem Cogn 27: 733–743, 2001; Humphreys et al. in J Exp Psychol Learn Mem Cogn 21: 961–980, 1995). According to Dean et al., the semantic interference effects in postcue picture naming occur because the integration of the object and the cued attribute in memory is more difficult for categorically related pictures than for unrelated pictures. The aim of this experiment was to determine whether this idea was true for postcue word pronunciation tasks. Participants completed two postcue tasks, one requiring pronunciation of the target word indicated by a locational cue and another requiring pronunciation of the location of a centrally presented word. Results indicated a semantic priming effect only for the locational cue condition suggesting that the integration of the cue and identity information was unaffected by word context. These data suggest that priming in a postcue word pronunciation task may be due to feedback from residual activation within the semantic system facilitating access to the target word’s phonology.     

Qualitative analysis of verbal fluency output: review and comparison of several scoring methods

We compared three approaches to scoring qualitative aspects of verbal fluency performance in 88 healthy young adults. Phonemic and semantic fluency output was scored for word clustering and switching between clusters. Convergent validity analyses using other tests presumed to tap into strategy use (California Verbal Learning Test, Ruff Figural Fluency Test) support scoring of phonemic and semantic clusters on both fluency tasks. Task-discrepant clustering (e.g., semantic clustering on phonemic fluency) may index intentional strategy use on both fluency tasks, whereas task consistent clustering (e.g., phonemic clustering on phonemic fluency) appears strategic only on semantic fluency. Switching can be decomposed into subtypes that appear to reflect different cognitive processes on phonemic versus semantic fluency. Principal components analyses suggest that earlier scoring methods do not fully capture the "process" aspects of verbal fluency performance.     

Are two heuristics better than one? The fluency and distinctiveness heuristics in recognition memory

Four experiments were conducted to test the impact of having multiple heuristics (distinctiveness and fluency) available during a recognition test. Recent work by Gallo, Perlmutter, Moore, and Schacter (Memory & Cognition 36:461–466, 2008) suggested that fluency effects are reduced when the distinctiveness heuristic can be applied to a recognition decision. In Experiment 1, we used a response reversal paradigm (Van Zandt & Maldonado-Molina Journal of Experimental Psychology: Learning, Memory, and Cognition 30:1147–1166, 2004) to demonstrate that participants transitioned from an early response strategy that was largely reliant on fluency to a later strategy in which the influences of fluency and distinctiveness were both observable. Experiments 2a, 2b, and 3 showed no evidence for reduction of the fluency heuristic after picture study when the test required a delayed response (Exp. 2a), confidence ratings (Exp. 2b), or the application of conceptual fluency (Exp. 3). The results are consistent with models of memory that assume that familiarity and recollection influence individual memory decisions Wixted (Psychological Review, 114:152–176, 2007).     

Differential impacts of age of acquisition on letter and semantic fluency in Alzheimer's disease patients and healthy older adults

The degree to which the typical age of acquisition (AoA) of words and word frequency have separable influences on verbal production tasks has been strongly debated. To examine the overlap between these factors in verbal fluency tasks, the performance of Alzheimer's disease (AD) patients (N = 34) and normal elderly controls (N = 36) was compared on semantic (e.g., vegetables) and letter (e.g., words that begin with F) fluency tasks. These comparisons revealed that words generated for the semantic fluency task had an earlier AoA while words generated for the letter fluency task had a higher word frequency. Differences in AoA between AD patients and controls were larger for semantic than letter fluency. These results suggest that AoA has an effect on verbal production that is independent of word frequency and that AoA has a semantic locus.     

Working memory in the oldest-old: evidence from output serial position curves

In the present study, we examined adult age differences in short-term and working memory performance in middle-aged (45–64 years), young–old (65–74 years), old–old (75–89 years), and oldest–old adults (90 years and over) in the Louisiana Healthy Aging Study. Previous research suggests that measures of working memory are more sensitive to age effects than are simple tests of short-term memory Bopp and Verhaeghen (Journal of Gerontology: Psychological Sciences 60:223–233, 2005), Myerson, Emery, White, and Hale, (Aging, Neuropsychology, and Cognition 10:20–27, 2003). To test this hypothesis, we examined output serial position curves of recall data from three span tasks: forward and backward digit span and size judgment span. Participants’ recall patterns in the size judgment span task revealed that the two oldest groups of adults showed the largest decreases in recall performance across output serial positions, but did not differ significantly from each other. Correlation analyses indicated the strongest negative correlation with age occurred with the size judgment span task. Implications of these findings for understanding strategic processing abilities in late life are discussed.     

Category and letter fluency in semantic dementia, primary progressive aphasia, and Alzheimer's disease

This study examined the impact of various degenerative dementias on access to semantic knowledge and the status of semantic representations. Patients with semantic dementia, primary progressive aphasia, and Alzheimer's disease were compared with elderly controls on tasks of category and letter fluency, with number of words generated, mean lexical frequency and errors recorded. The findings are consistent with the view that category and letter fluency rely on both common and unique cognitive processes. Fluency tasks, with the richness of data obtained, are valuable in distinguishing different dementia syndromes from one another.     

Both-edges representation of letter position in reading

The representations that underlie our ability to read must encode not only the identities of the letters in a word, but also their relative positions. In recent years, many new proposals have been advanced concerning the representation of letter position in reading, but the available data do not distinguish among the competing proposals; multiple theories, each positing a different letter position representation scheme, are compatible with the evidence. In this article, we report two experiments that used the illusory word paradigm (e.g., Davis & Bowers, Journal of Experimental Psychology: Human Perception and Performance, 30: 923–941, 2004) to distinguish among alternative schemes for representing letter position in reading. The results support a scheme that uses both the beginning and the end of a word as anchoring points. This both-edges scheme has been implicated in letter position representation in spelling (Fischer-Baum, McCloskey, & Rapp, Cognition, 115: 466–490, 2010), as well as in position representation in verbal working memory (Henson, Memory & Cognition, 27: 915–927, 1999), suggesting that it may be a domain-general scheme for representing position in a sequence.     

Age-related Differences in Episodic Odour Recognition: The Role of Access to Specific Odour Names

This study addressed the relationship between semantic memory variables and episodic odour recognition across the adult lifespan. Young (19–34 years), young-old (60–69 years), and old women (70–79 years) were tested in a number of measures of semantic memory: letter fluency, category fluency, vocabulary, odour familiarity, and odour naming. Odour recognition memory was assessed on two occasions: immediately after and 48 hours after inspection. Young women outperformed both groups of older women in odour recognition and odour naming, although the two older age groups did not differ. For all age groups, performance declined from immediate to delayed testing. Individual differences in fluency and vocabulary did not predict performance in odour recognition. Rather, odour recognition was related to the subjects' specific semantic knowledge of the odour, as indexed by familiarity and accuracy in odour naming. Hierarchical regression analyses indicated that age and odour naming were the most potent variables in predicting performance in both immediate and delayed odour recognition. Controlling for odour naming resulted in the effect of age disappearing, indicating the pivotal role of accessibility of odour names for successful episodic odour recognition, and for age-related differences in odour recognition.     

Pervasive influence of semantics in letter and category fluency: a multidimensional approach

We used multidimensional statistical procedures to study semantic and lexical processes underlying word retrieval in verbal-fluency performance. Forty healthy participants were given a two-choice letter task (i.e., generate items beginning with the letter 'A' or 'F', in any order) and a two-choice category task (i.e., generate animal or fruit names, in any order). Using correspondence analysis (CoA) and hierarchical clustering (HC), we found evidence of prominent semantic organization in both letter and category fluency. For example, a striking categorical segregation between animate and inanimate entities emerged during the letter task. Analysis of inter-item times revealed strong sequential priming effects in both tasks. Taken together, these results indicate that semantic facilitation is pervasive in word retrieval processes, even in the letter-fluency task, and therefore suggest that the traditional view of letter fluency as a purely phonemically based task should be revised. Finally, our findings may help explain patterns of verbal-fluency measures obtained in focal brain lesion patients.     

Reading First kindergarten classroom instruction and students' growth in phonological awareness and letter naming–decoding fluency

This study investigated the role of the amount, content, and implementation of reading instruction provided by 17 kindergarten teachers in eight Reading First elementary schools as it related to students' progress (n = 286 students) on early reading assessments of phonological awareness and letter naming–decoding fluency. Children's phonological awareness and letter naming–decoding fluency grew significantly from fall to spring. On average, across the three 60 min observations, teachers provided over 30 min a day of phonological awareness and phonics instruction and 15 min a day of vocabulary and comprehension instruction. Global ratings of instructional quality revealed two implementation factors: explicit and individualized implementation and meaningful interactions around text. Hierarchical linear modeling revealed that the amounts of specific instructional content, as well as how this instruction was implemented, was related to students' letter knowledge and phonological awareness skill growth.     

Reporting of Subscores Using Multidimensional Item Response Theory

Recently, there has been increasing interest in reporting subscores. This paper examines reporting of subscores using multidimensional item response theory (MIRT) models (e.g., Reckase in Appl. Psychol. Meas. 21:25–36, 1997; C.R. Rao and S. Sinharay (Eds), Handbook of Statistics, vol. 26, pp. 607–642, North-Holland, Amsterdam, 2007; Beguin & Glas in Psychometrika, 66:471–488, 2001). A MIRT model is fitted using a stabilized Newton–Raphson algorithm (Haberman in The Analysis of Frequency Data, University of Chicago Press, Chicago, 1974; Sociol. Methodol. 18:193–211, 1988) with adaptive Gauss–Hermite quadrature (Haberman, von Davier, & Lee in ETS Research Rep. No. RR-08-45, ETS, Princeton, 2008). A new statistical approach is proposed to assess when subscores using the MIRT model have any added value over (i)  the total score or (ii)  subscores based on classical test theory (Haberman in J. Educ. Behav. Stat. 33:204–229, 2008; Haberman, Sinharay, & Puhan in Br. J. Math. Stat. Psychol. 62:79–95, 2008). The MIRT-based methods are applied to several operational data sets. The results show that the subscores based on MIRT are slightly more accurate than subscore estimates derived by classical test theory.     

Verbal fluency in children with ADHD: Strategy using and temporal properties

Verbal fluency tasks are commonly used in cognitive and developmental neuropsychology in assessing executive functions, language skills as well as divergent thinking. Twenty-two typically developing children and 22 children with ADHD between the ages of 8 and12 years were examined using verbal fluency tasks, prepotent response inhibition, and working memory tests. The clinical group showed impaired inhibitory and spatial working memory processes. We used different qualitative analyses of verbal fluency tasks to explore the lexical and executive strategies (word clustering and switching), and the temporal properties of the responses. Children with ADHD had a leeway in applying relevant lexical or executive strategies related to difficulties in strategy using. The reduced efficiency of children with ADHD in semantic fluency task is based on suboptimal shifting between word clusters and is related to the lack of ability of producing new clusters of items. The group difference appeared at the level of accessing and/or activating common words; however, the executive process of searching the lexicon extensively is intact.     

The Lexical Stroop Sort (LSS) picture-word task: a computerized task for assessing the relationship between language and executive functioning in school-aged children

The relationship between language development and executive function (EF) in children is not well understood. The Lexical Stroop Sort (LSS) task is a computerized EF task created for the purpose of examining the relationship between school-aged children’s oral language development and EF. To validate this new measure, a diverse sample of school-aged children completed standardized oral language assessments, the LSS task, and the widely used Dimensional Change Card Sort (DCCS; Zelazo, 2006) task. Both EF tasks require children to sort stimuli into categories based on predetermined rules. While the DCCS largely relies on visual stimuli, the LSS employs children’s phonological loop to access their semantic knowledge base. Accuracy and reaction times were recorded for both tasks. Children’s scores on the LSS task were correlated with their scores on the DCCS task, and a similar pattern of relationships emerged between children’s vocabulary and the two EF tasks, thus providing convergent validity for the LSS. However, children’s phonological awareness was associated with their scores on the LSS, but not with those on the DCCS. In addition, a mediation model was used to elucidate the predictive relationship between phonological awareness and children’s performance on the LSS task, with children’s vocabulary fully mediating this relationship. The use of this newly created and validated LSS task with different populations, such as preschoolers and bilinguals, is also discussed.