The Modified Five-Point Test (MFPT): normative data for a sample of Italian elderly.

INTRODUCTION: Non-verbal figural fluency is related to executive functions and specifically to the ability to create as many unique designs as possible, while minimizing their repetitions. An Italian version of figural fluency is the Modified Five-Point Test (MFPT), which is highly employed in the clinical practice of neuropsychologists. To date, reference data of Italian population are limited to a sample aged between 16 and 60 years old. Thus, the current study aims to provide normative data of the MFPT in the context of a population-based setting, conducted in Southern Italy. MATERIAL AND METHODS: We collected N = 340 Italian healthy subjects, aged over 65 years old (range: 65-91), pooled across subgroups for age, sex, and education. Multiple regression analyses were performed to estimate the effect of age, education, and sex on the participant's performance. Equivalent scores and cut-off scores were also defined for the number of unique designs (UDs) and the number of strategies (CSs). RESULTS: Multiple regression analyses revealed that UDs increase with decreasing age and increasing educational level. CSs are influenced by higher educational levels but neither by age nor sex. A significant inverse correlation between the UDs and percentage of errors occurred, suggesting that a higher number of UDs are associated with a fewer number of errors and higher CSs employed. CONCLUSION: The MFPT provides a measure of cognitive functioning in terms of the ability to initiate and realize designs, affording useful hints for clinical settings. The MFPT may represent a handy and useful tool with a specific focus in the differentiation of healthy versus pathological aging.

The contribution of the frontal lobe to creativity. Insights from epilepsy.

PURPOSE: This study was aimed to evaluate the impact of frontal (FLE) and temporal lobe epilepsy (TLE) on graphic creativity. METHODS: A hundred and six patients with FLE (n = 32) or TLE (n = 74) and 38 healthy subjects underwent a design fluency (DF) test constituted by a free and a fixed condition. For each condition, the number of correct designs, as an index of creativity, and unacceptable nonperseveration or perseveration designs were calculated. The participants also underwent a comprehensive neuropsychological battery. RESULTS: The number of novel correct designs significantly differed between the groups: patients with FLE produced fewer designs than patients with TLE and controls, while epilepsy laterality had no effect. Patients with FLE also produced more unacceptable nonperseveration designs than controls, with no between-group differences in the perseverations. The number of novel designs was predicted by the type of epilepsy, whereas word fluency, comprehension, attention, set shifting, visual matching, and constructive praxis had no influence. This score was a sensitive marker of FLE discriminating FLE cognitive pattern from the pattern of TLE and healthy condition. CONCLUSIONS: Left or right FLE, but not TLE, can impair graphic creativity. This finding and that DF was unrelated to other cognitive abilities suggest that creativity is a specific domain, sensitive to epilepsy-related frontal lobe dysfunctions. This behavioral approach including test accuracy may have implications in defining FLE cognitive phenotype.

Design fluency and neuroanatomical correlates in 54 neurosurgical patients with lesions to the right hemisphere.

We addressed the neuroanatomical correlates of 54 right-brain-damaged neurosurgical patients on visuo-spatial design fluency, which is a measure of the ability to generate/plan a series of new abstract combinations in a flexible way. 22.2% of the patients were impaired. They failed the task because they did not use strategic behavior, in particular they used rotational strategy to a significantly lower extent and produced a significantly higher rate of perseverative errors. Overall performance did not correlate with neuropsychological tests, suggesting that proficient performance was independent of other cognitive domains. Performance significantly correlated with use of rotational strategy. Tasks related to executive functions such as psychomotor speed and capacity to shift were positively correlated to the number of strategies used to solve the task. Lesion analysis showed that the maximum density of the patients' lesions-obtained by subtracting the overlap of lesions of spared patients from the overlap of lesions of impaired patients-overlaps with the precentral gyrus, rolandic operculum/insula, superior/middle temporal gyrus/hippocampus and, at subcortical level, with part of the superior longitudinal fasciculus, external capsule, retrolenticular part of the internal capsule and sagittal stratum (inferior longitudinal fasciculus and inferior fronto-occipital fasciculus). These areas are part of the fronto-parietal-temporal network known to be involved in top-down control of visuo-spatial attention, suggesting that the mechanisms and the strategies needed for proficient performance are essentially visuo-spatial in nature.

Verbal and Non-verbal Fluency in Adults with Developmental Dyslexia: Phonological Processing or Executive Control Problems?

The executive function of fluency describes the ability to generate items according to specific rules. Production of words beginning with a certain letter (phonemic fluency) is impaired in dyslexia, while generation of words belonging to a certain semantic category (semantic fluency) is typically unimpaired. However, in dyslexia, verbal fluency has generally been studied only in terms of overall words produced. Furthermore, performance of adults with dyslexia on non-verbal design fluency tasks has not been explored but would indicate whether deficits could be explained by executive control, rather than phonological processing, difficulties. Phonemic, semantic and design fluency tasks were presented to adults with dyslexia and without dyslexia, using fine-grained performance measures and controlling for IQ. Hierarchical regressions indicated that dyslexia predicted lower phonemic fluency, but not semantic or design fluency. At the fine-grained level, dyslexia predicted a smaller number of switches between subcategories on phonemic fluency, while dyslexia did not predict the size of phonemically related clusters of items. Overall, the results suggested that phonological processing problems were at the root of dyslexia-related fluency deficits; however, executive control difficulties could not be completely ruled out as an alternative explanation. Developments in research methodology, equating executive demands across fluency tasks, may resolve this issue. Copyright © 2017 John Wiley & Sons, Ltd.

Group administration influences design but not written word fluency testing.

Quicker assessments of right and left frontal lobe function, such as the examination of performance on design and language fluency tasks, respectively, lend themselves to a group administration setting. However, the influence of social facilitation factors on a dissociation model in these group settings is not well understood. One hundred college students (71 women) completed design and written word fluency tasks while sitting beside a faster or slower working confederate. Questionnaires related to trait worry, emotion regulation, state depression, anxiety and stress were completed following these tasks. Students in the fast condition produced significantly more unique designs, but there was no condition difference on written word fluency. This finding indicated that performance on a design task, which requires relative right frontal activation, may decrease if the subject is paired with a slow working confederate. High trait worriers demonstrated reduced performance on the design task (as indicated by higher design error ratios) but preserved performance on the word task. This supported a single dissociation in that performance on these tasks indicates compromised right hemisphere function and preserved left hemisphere function, respectively, in high trait worriers.

Cross-cultural comparison of the performance on the Five-Point test between highly educated comparable samples of Argentina and South Africa.

OBJECTIVE: The study aimed to carry out a cross-cultural analysis by comparing Five-Point test scores for two different countries. The Five-Point test measures design fluency, an executive function, and is an inexpensive test that makes it more accessible to assessment settings, including under-resourced settings. METHODS: Adults in Argentina (n = 90) and South Africa (n = 90) with tertiary levels of education were tested on the Five-Point Test. ANOVA was applied to compare the scores of the two groups on the total number of unique designs produced (Total Unique Designs). RESULTS: The study found no significant differences in the Total Unique Designs scores between the two groups (p = .13; η = 0.01). Correlations between demographic variables and the Total Unique Designs scores varied slightly across both samples. CONCLUSIONS: Despite large cultural differences between both samples (language, race, religion, income) scores on this test did not differ significantly. These findings provide initial evidence of scalar equivalence on the test across these samples. Norms for the Five-Point Test Total Unique Designs scores might be used interchangeably between these two highly educated groups from different countries.

A Longitudinal Study of the Development of Executive Function and Calibration Accuracy.

This longitudinal study examined the development of executive function and calibration accuracy in preadolescents. This study's sample consisted of 262 students (127 females) from grades 4 (n = 91), 5 (n = 89), and 6 (n = 82) who took measures of executive function and performance calibration in a sport task three times over 20 months. A latent growth-curve modeling analysis showed a significant relationship between the rates of change of executive function and calibration accuracy. The results also showed a dynamic interplay in the development of executive function and calibration accuracy. There were significant interindividual differences in the estimated population means both in executive function and calibration accuracy and in the rate of change of executive function, but not in the rate of change of calibration accuracy. The age of the participants had a positive effect only on the estimated population mean of executive function.

Cognitive flexibility is associated with sickness resilience.

Psychological constructs related to health outcomes and well-being, such as metacognitive beliefs, have been linked to executive functions in general, and cognitive flexibility more specifically. However, such effects have previously only been discussed on a theoretical level and behavioral flexibility has most often been measured through self-report, only approximating information processing capacities. Objectively measured executive functions may be a more potent predictor of health outcomes. We set out to test whether cognitive flexibility capacity was associated with sick leave in a medium sized company. We included 111 subjects of widely different occupations and assessed their executive functions using Delis-Kaplan Executive Function System test battery (D-KEFS). To assess cognitive flexibility capacity, we included Design Fluency (DF) and Verbal Fluency (VF) and computed these into an index of cognitive flexibility (DFVF). Detailed information on sick leave for the last 5 years was gathered from the company. Our results showed that there was a significant negative correlation between DFVF and sick leave [rs(109) = -0.23, p = 0.015] in the full group as well as in the group that had at least 1 day of sick leave [rs(72) = -0.25, p = 0.03]. The results withstood adjustment for sex, age, occupation, and several core executive functions as well as autistic and ADHD-traits. The results remained for separate analyses using DF or VF. Our main findings were conceptually replicated in a group of bipolar disorder patients. This study shows that objectively measured capacity of cognitive flexibility is associated with key health outcomes such as sick leave.

Acute Effects of Exergaming on Students' Executive Functions and Situational Interest in Elementary Physical Education.

Two studies were conducted to examine the acute effects of exergaming on students' executive functions and to explore their situational interest regarding these games in elementary physical education. The first study involved a two-group, repeated measures, cross-over quasi-experimental design. Participants were 74 (36 boys) fourth- and fifth-grade students who were assigned to the experimental (38 students) and the waiting list control (36 students) group. The single physical education session with exergames was first implemented with the initial experimental group and after the post-test, the waiting list control group received the intervention. In the second study, a pre-test post-test, within-subjects design was involved with the experimental group students (48 fourth- and fifth-grade students, 27 boys) who participated in a booster single physical education session with exergames two months after their involvement in a four-week intervention with cognitively challenging physical activity games. Both studies involved pre- and post-intervention measures for executive functions using the design fluency test and a post-test measure for situational interest. During the acute session, students had to follow the movements of an on-screen dancing character in time to a chosen song of the Just Dance 2015 exergame. The results of the first study showed that experimental group students improved significantly from pre- to post-test their scores in design fluency and in cognitive flexibility and in the total score of the design fluency test and their improvements were higher compared to the waiting list control group. The waiting list control group students, after receiving the acute session with exergames, significantly improved their scores in design fluency, inhibition, and cognitive flexibility and in the total score of the design fluency test compared to their pre-intervention scores. Moreover, the second study showed that students' total score in the design fluency test improved significantly from pre- to post-intervention. In both studies, students reported generally high scores in all subscales of the situational interest questionnaire. These results suggested that an acute exergame-based physical education session attracted students' interest and positively triggered their executive functions.

The Effects of Cognitively Challenging Physical Activity Games versus Health-Related Fitness Activities on Students' Executive Functions and Situational Interest in Physical Education: A Group-Randomized Controlled Trial.

This study compared cognitively challenging physical activity games and health-related fitness activities in terms of their effects on students' executive functions and situational interest in physical education. A total of 102 fourth- and fifth-grade students (56 boys, 46 girls) participated in this study. A group-randomized controlled trial design involving an acute experiment was used. Two intact classes of students (one fourth-grade and one fifth-grade) were randomly assigned to each one of the three groups. Students in Group 1 participated in cognitively challenging physical activity games, students in Group 2 participated in activities for developing their health-related fitness, and Group 3 students were the control group without physical education. Executive functions were measured pre- and post-intervention with the design fluency test, whereas situational interest was only measured post-intervention with the situational interest scale. Group 1 students who played cognitively challenging physical activity games had increased their executive functions' scores more than the Group 2 students involved in health-related fitness activities. Students of both these groups outperformed control group students. Moreover, Group 1 students reported higher levels of instant enjoyment and total interest than Group 2 students. The results of this study suggest that cognitively challenging physical activity games can be an effective means for enhancing executive functions, and motivate students to be involved in interesting and enjoyable forms of physical activity.

Measures of figural fluency: Relationship to neuropsychological variables and traumatic brain injury severity.

Figural fluency tests were originally developed as a measure of right frontal lobe integrity and are presently a standard component of neuropsychological evaluation. To better understand the clinical interpretation of figural fluency scores (design output and perseverative errors), the current study investigated two trials from the Ruff Figural Fluency Test (RFFT) and their correlations with other neuropsychological variables in examinees who were being evaluated for cognitive difficulties (N = 84). Design output was significantly correlated (rs > .4) with psychomotor speed, non-verbal memory, and false positive recognition errors on a verbal memory test, while perseverative errors did not show a significant correlation with these variables or with design output. Design output also showed a significant correlation with phonemic fluency (rs > .3) as well as correlations (rs > .25) with semantic fluency and intellectual functioning. In a sample of examinees with mild (n = 33), complicated-mild (n = 11), and moderate-severe (n = 16) traumatic brain injuries (TBI), group differences in design output did not reach significance, whereas perseverative errors were significantly related to the severity of injury. This study suggests that design output and perseverative errors on figural fluency may be separate measures, and their clinical interpretations are discussed.

Capturing Subtle Neurocognitive Differences in Children with and without Tourette Syndrome through a Fine-Grained Analysis of Design Fluency Profiles.

BACKGROUND: Tourette syndrome (TS) can be accompanied by neurocognitive impairment. Only a few studies have focused on executive function assessment in TS using design fluency, providing preliminary results. This study aimed to characterize the detailed design fluency profile of children with TS compared with neurotypical children, while addressing the central concern of frequent comorbidities in studies on TS by considering tic severity and attention-deficit/hyperactivity disorder (ADHD) symptoms and diagnosis. METHODS: Sixty-one children aged between 6 and 15 years participated and were divided into a TS group (n = 28 (with ADHD n = 15)) and a control group (n = 33). Our objective was addressed by examining a wide range of measures of the Five-Point-Test, presumably sensitive to frontostriatal dysfunction. The total number of designs, repetitions, repetition ratio, unique designs, and numerical, spatial, and total strategies were examined for the total duration of the test (global measures) and at five equal time intervals (process measures). RESULTS: The TS group produced significantly fewer numerical strategies. Groups did not differ in other global or process measures. ADHD did not affect performance. CONCLUSIONS: Children with TS do not inherently show general executive dysfunction but may present with subtle neurocognitive characteristics here revealed by comprehensive design fluency profiles.

Executive Functions of Swedish Counterterror Intervention Unit Applicants and Police Officer Trainees Evaluated With Design Fluency Test.

Executive functions (EF) represent higher order top-down mechanisms regulating information processing. While suboptimal EF have been studied in various patient groups, their impact on successful behavior is still not well described. Previously, it has been suggested that design fluency (DF)-a test including several simultaneous EF components mainly related to fluency, cognitive flexibility, and creativity-predicts successful behavior in a quickly changing environment where fast and dynamic adaptions are required, such as ball sports. We hypothesized that similar behaviors are of importance in the selection process of elite police force applicants. To test this hypothesis, we compared elite police force applicants (n = 45) with a control group of police officer trainees (n = 30). Although both groups were better than the norm, the elite police force applicants had a significantly better performance in DF total correct when adjusting for sex and age [F(1,71) = 18.98, p < 0.001]. To understand how this capacity was altered by stress and tiredness, we re-tested the elite police force applicants several days during an extreme field assessment lasting 10 days. The results suggested that there was a lower than expected improvement in DF total correct and a decline in the DF3-subtest that includes a larger component of cognitive flexibility than the other subtests (DF1 and DF2). Although there was a positive correlation between the baseline session and the re-test in DF3 [r(40) = 0.49, p = 0.001], the applicants having the highest scores in the baseline test also displayed the largest percentage decline in the re-test [r(40) = -0.46, p = 0.003]. In conclusion, our result suggests that higher order EF (HEF) that include cognitive flexibility and creativity are of importance in the application for becoming an elite police officer but relatively compromised in a stressful situation. Moreover, as the decline is different between the individuals, the results suggest that applicants should be tested during baseline conditions and during stressful conditions to describe their cognitive capacity fully.

Resting-state hyperconnectivity within the default mode network impedes the ability to initiate cognitive performance in first-episode schizophrenia patients.

Among multiple cognitive impairments present in schizophrenia, a decline in fast information processing is one of the most severe neuropsychological deficit. Reduced ability to efficiently launch a coherent cognitive activity might be a significant factor contributing to poor results in time-limited tasks obtained by schizophrenia patients. The aim of this study was to identify neurophysiological predictors of expected cognitive initiation failures in a group of first-episode schizophrenia individuals (SZ). To evaluate the effectiveness of initiation, a dynamic analysis of design fluency test was applied, assessing to what extent the productivity was focused within the first interval of the performance, what is a typical way healthy subjects execute this task. Resting-state EEG recordings were obtained from SZ patients (n = 34) and controls (n = 30) to examine functional connectivity between 84 intra-cortical current sources determined by eLORETA (exact low-resolution brain electromagnetic tomography) for six conventionally analyzed frequencies. The nonparametric randomization approach was used to identify hypo- and hyper-connections, i.e. synchronizations significantly differentiating the studied samples in terms of connectivity strength. Generally, SZ patients obtained poor outcomes in fluency test and dynamic analysis of performance confirmed the presence of initiation deficit in clinical sample, which was a single factor explaining the intergroup difference regarding the entire task. In the majority of frequencies, the arrangement of synchronizations in SZ group was dominated by hypo-connections, except for the theta band, in which the strength of synchronizations between posterior cingulate cortex, cuneus and precuneus was significantly higher for SZ group. These theta-band hyper-connections turned out to be significant predictors of cognitive initiation failure in the clinical sample. Additionally, theta hyper-connections correlated negatively with the total number of unique designs generated by patients, however, the strength of this correlation was weaker than regarding initiation index. The results of this study suggest that baseline hyperconnectivity within the posterior hub of the Default Mode Network, containing posterior cingulate gyrus and precuneus, might disturb effective cognitive outcome, not only by interfering with task-positive functional networks but also by delaying the starting phase of performance, which might be specifically deleterious for the execution of time-limited tests.

Correspondence of Maximum and Typical Performance Measures of Cognitive Processing.

We examined associations among cognitive processing measures that varied on a continuum from maximum to typical performance tasks in the context of an ego depletion study. Our intent was to replicate and extend the findings of Charek, Meyer, and Mihura, which showed that ego depletion had an expected effect on selected scores from the Rorschach inkblot task. We hypothesized that Rorschach variables indicative of cognitive sophistication would correlate with neuropsychological measures of cognitive ability and that Rorschach variables theoretically unassociated with cognitive processing would not correlate with those criterion measures. These hypotheses were supported, providing evidence of convergent and discriminant validity. We also hypothesized ego depletion effects on all measures; however, none were evident. Methodological considerations and implications of the findings are discussed.

Fluency and rule breaking behaviour in the frontal cortex.

Design (DF) and phonemic fluency tests (FAS; D-KEFS, 2001) are commonly used to investigate voluntary generation. Despite this, several important issues remain poorly investigated. In a sizeable sample of patients with focal left or right frontal lesion we established that voluntary generation performance cannot be accounted for by fluid intelligence. For DF we found patients performed significantly worse than healthy controls (HC) only on the switch condition. However, no significant difference between left and right frontal patients was found. In contrast, left frontal patients were significantly impaired when compared with HC and right frontal patients on FAS. These lateralization findings were complemented, for the first time, by three neuroimaging; investigations. A traditional frontal subgrouping method found significant differences on FAS between patients with or without Left Inferior Frontal Gyrus lesions involving BA 44 and/or 45. Parcel Based Lesion Symptom Mapping (PLSM) found lower scores on FAS were significantly associated with damage to posterior Left Middle Frontal Gyrus. An increase in rule break errors, so far only anecdotally reported, was associated with damage to the left dorsal anterior cingulate and left body of the corpus callosum, supporting the idea that conflict resolution and monitoring impairments may play a role. Tractwise statistical analysis (TSA) revealed that patients with disconnection; in the left anterior thalamic projections, frontal aslant tract, frontal; orbitopolar tract, pons, superior longitudinal fasciculus I and II performed significantly worse than patients without disconnection in these tracts on FAS. In contrast, PLSM and TSA analyses did not reveal any significant relationship between lesion location and performance on the DF switch condition. Overall, these findings suggest DF may have limited utility as a tool in detecting lateralized frontal executive dysfunction, whereas FAS and rule break behavior appears to be linked to a set of well localized left frontal grey matter regions and white matter tracts.

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.

Spreading activation in nonverbal memory networks.

Theories of spreading activation primarily involve semantic memory networks. However, the existence of separate verbal and visuospatial memory networks suggests that spreading activation may also occur in visuospatial memory networks. The purpose of the present investigation was to explore this possibility. Specifically, this study sought to create and describe the design frequency corpus and to determine whether this measure of visuospatial spreading activation was related to right hemisphere functioning and spreading activation in verbal memory networks. We used word frequencies taken from the Controlled Oral Word Association Test and design frequencies taken from the Ruff Figural Fluency Test as measures of verbal and visuospatial spreading activation, respectively. Average word and design frequencies were then correlated with measures of left and right cerebral functioning. The results indicated that a significant relationship exists between performance on a test of right posterior functioning (Block Design) and design frequency. A significant negative relationship also exists between spreading activation in semantic memory networks and design frequency. Based on our findings, the hypotheses were supported. Further research will need to be conducted to examine whether spreading activation exists in visuospatial memory networks as well as the parameters that might modulate this spreading activation, such as the influence of neurotransmitters.

Cognitive screening in Multiple Sclerosis: the Five-Point Test as a substitute for the PASAT in measuring executive function.

OBJECTIVE: The Paced Auditory Serial Addition Test (PASAT) is frequently employed to measure executive functions in patients with Multiple Sclerosis (MS). In the past, the PASAT has often been criticized because of its stressful and demanding requirements. Continuous utilization might also reduce its validity. The Five-Point Test (FPT) by Regard, Strauss, and Knapp ((1982) Children's production on verbal and non-verbal fluency tasks. Perceptual and Motor Skills, 55, 839-844.) is a short test of figural fluency which might serve as a substitute. METHOD: 116 patients diagnosed with MS were tested with a short version of the Brief Repeatable Battery (BRB) by Rao and the Cognitive Function Study Group of the National Multiple Sclerosis Society including the PASAT, as well as the FPT. A factor analysis was computed and the frequency of cognitive impairment was calculated for both the original short version of the BRB and the alternative version (involving the FPT). RESULTS: In the factor analysis, PASAT and FPT loaded highest on the same factor (two factors were extracted). The estimation of the frequency of cognitive impairment showed that replacing the PASAT with the FPT did not considerably alter the proportion of patients identified as cognitively impaired. CONCLUSIONS: The FPT proved to be a viable alternative to the PASAT in this study. It may be recommended as a possible replacement in neuropsychological screening of MS-patients with the advantage of avoiding the indicated limitations of the PASAT.

Category and design fluency in mild cognitive impairment: Performance, strategy use, and neural correlates.

The exploration and retrieval of words during category fluency involves different strategies to improve or maintain performance. Deficits in that task, which are common in patients with amnestic mild cognitive impairment (aMCI), mirror either impaired semantic memory or dysfunctional executive control mechanisms. Relating category fluency to tasks that place greater demands on either semantic knowledge or executive functions might help to determine the underlying cognitive process. The aims of this study were to compare performance and strategy use of 20 patients with aMCI to 30 healthy elderly controls (HC) and to identify the dominant component (either executive or semantic) for better task performance in category fluency. Thus, the relationship between category fluency, design fluency and naming was examined. As fluency tasks have been associated with the superior frontal gyrus (SFG), the inferior frontal gyrus (IFG), and the temporal pole, we further explored the relationship between gray matter volume in these areas and both performance and strategy use. Patients with aMCI showed significantly lower performance and significantly less strategy use during fluency tasks compared to HC. However, both groups equally improved their performance when repeatedly confronted with the same task. In aMCI, performance during category fluency was significantly predicted by design fluency performance, while in HC, it was significantly predicted by naming performance. In HC, volume of the SFG significantly predicted both category and design fluency performance, and strategy use during design fluency. In aMCI, the SFG and the IFG predicted performance during both category and design fluency. The IFG significantly predicted strategy use during category fluency in both groups. The reduced category fluency performance in aMCI seems to be primarily due to dysfunctional executive control mechanisms rather than impaired semantic knowledge. This finding is directly relevant to patients in the different stages of Alzheimer's disease as it links the known semantic fluency deficit in this population to executive functions. Although patients with aMCI are impaired in both performance and strategy use compared to HC, they are able to increase performance over time. However, only HC were able to significantly improve the utilization of fluency strategies in both category and design fluency over time. HC seem to rely more heavily on the SFG during fluency tasks, while in patients with aMCI additional frontal brain areas are involved, possibly reflecting compensational processes.