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Validity of the Boston qualitative scoring system for the Rey-Osterrieth complex figure among depressed elderly patients.

A recent qualitative scoring method for the Rey-Osterrieth Complex Figure (ROCF), the Boston Qualitative Scoring System (BQSS), purports to assess visuospatial organization, visual memory and executive function by using multiple series of scores with well-defined criteria. The first objective of this study was to determine whether the BQSS cores correlated with scores derived from the tradition Osterrieth scoring method and which method was more efficient at separating the diagnostics groups. The second objective was to correlate the BQSS executive scores to other nonverbal and verbal tests of executive function, working memory, processing speed, and episodic memory to determine what cognitive abilities the BQSS scores were measuring. The subjects, older depressed patients and healthy controls, were free of any clinical sign of incipient dementia or comorbid neurological disease. Their ROCF drawings were scored using both the Osterrieth and BQSS methods. The BQSS summary drawing scores correlated well with the Osterrieth summary scores for the copy and short-delay recall phases, the percent retained over the delay period and recognition. The BQSS executive scores for Planning, which included both copy and recall phases, correlated with Matrix Reasoning indicating that they assessed nonverbal reasoning but they did not correlate with other traditional executive tests. Planning also contributed to the separation of diagnostics groups and was the most effective score for predicting the percent of the ROCF retained over a short delay. The remaining executive scores did not show a pattern of correlations with other nonverbal executive or working memory scores that would satisfy concerns regarding their interpretation or internal validity when used in an older and/or depressed population. No differences emerged between the two scoring methods in their efficiency for predicting depression.

Aged↗

Frontal lobe damage and tests of executive processing: a meta-analysis of the category test, stroop test, and trail-making test.

The Category Test, Trails B, and the interference task of the Stroop Test are among the most commonly administered measures of frontal lobe functioning and are thought to tap different cognitive functions mediated by these brain regions. Two meta-analyses were conducted on these tests to determine their sensitivity to frontal and lateralized frontal brain damage. Study 1 compared participants with frontal lobe damage to those with damage to posterior brain regions, whereas Study 2 compared participants with left and right frontal lobe damage. For each study, effect sizes based on performance differences between the above groups were calculated for the Category Test, Trail-Making Test Parts A and B, and the Stroop Test, including Word, Color, and Color-Word subtests. In Study 1 significant differences between groups were found for Trails A and all Stroop tasks, but in Study 2 the only difference between left and right frontal participants was on the Stroop Color-Word task. Potential reasons why Trails A and the Stroop Test are sensitive to frontal lobe damage are discussed, such as novelty and processing speed, as are clinical implications of these findings. The challenges of research on assessment of frontal lobe functioning are discussed and new developments in this area are highlighted.

Adult↗

Reliability and validity of useful field of view test scores as administered by personal computer.

The Useful Field of View test (UFOV(1)) is a measure of processing speed that predicts driving performance and other functional abilities in older adults. In comparison to a number of other visual and cognitive measures, the UFOV measure has consistently been found to be the strongest predictor of motor vehicle crashes of older adults. This measure has valuable applications in that computerized, performance-based measures that are predictive of crashes in the elderly population can provide an objective criterion for determining the need for driver restriction or rehabilitation. Administration of the UFOV test has evolved from the standard version (administered via touch-screen with the Visual Attention Analyzer) to two briefer versions, which are administered on a personal desktop computer (PC) using either a touch screen or mouse response option. These new versions of the test are briefer and require less specialized equipment, making the test more portable and practical for use in clinical settings. This study examined the reliability and validity of the scores from these two new versions. Results indicate that test-retest reliabilities of the scores from the UFOV PC versions are high (r's= 0 .884 for mouse and 0.735 for touch), and performance on both PC versions correlates well with performance on the standard version (r's = 0.658 for mouse and 0.746 for touch). Furthermore, scores were highly correlated (r = 0.916) when participants used either a touch screen or a mouse to input responses. In conclusion, the reliability and validity coefficients are of sufficient magnitude to make the touch and mouse PC versions of the UFOV practical for use in clinical evaluations.

Aged↗

Comparison of adult age differences in verbal and visuo-spatial memory: the importance of 'pure', parallel and validated measures.

The study compared age-related decrements in verbal and visuo-spatial memory across a broad elderly adult age range. Twenty-four young (18-25 years), 24 young-old (65-74 years), 24 middle-old (75-84 years) and 24 old-old (85-93 years) adults completed parallel recall and recognition measures of verbal and visuo-spatial memory from the Doors and People Test (Baddeley, Emslie & Nimmo-Smith, 1994). These constituted 'pure' and validated indices of either verbal or visuo-spatial memory. Verbal and visuo-spatial memory declined similarly with age, with a steeper decline in recall than recognition. Unlike recognition memory, recall performance also showed a heightened decline after the age of 85. Age-associated memory loss in both modalities was largely due to working memory and executive function. Processing speed and sensory functioning (vision, hearing) made minor contributions to memory performance and age differences in it. Together, these findings demonstrate common, rather than differential, age-related effects on verbal and visuo-spatial memory. They also emphasize the importance of using 'pure', parallel and validated measures of verbal and visuo-spatial memory in memory ageing research.

Adolescent↗

Lateral and central presentation of words with limited exposure duration as remedial training for reading disabled children.

In two studies it is examined whether lateral presentation of words in remedial practice for reading disabled children has additional effects to central presentation. The effect of limited exposure duration (LED) is also studied as a possible factor in inducing higher level decoding processes or increased processing speed of words. Two groups of Dutch reading disabled children (n1 = 25, mean age = 9;8 years and n2 = 36, mean age = 7;1 years) repeatedly practiced reading words presented in the left, right or the central visual field. The results show that all children improved substantially both in reading speed and accuracy, which demonstrates the importance of repetitive practice in reading to attain fluency in reading disabled children. Further analysis demonstrated that neither site of presentation nor limited exposure duration added significantly to the training results. These findings do not corroborate neuropsychological theories suggesting a special role for lateral presentations.

Child↗

WAIS-III index score profiles in the Canadian standardization sample.

Representative index score profiles were examined in the Canadian standardization sample of the Wechsler Adult Intelligence Scale-Third Edition (WAIS-III). The identification of profile patterns was based on the methodology proposed by Lange, Iverson, Senior, and Chelune (2002) that aims to maximize the influence of profile shape and minimize the influence of profile magnitude on the cluster solution. A two-step cluster analysis procedure was used (i.e., hierarchical and k-means analyses). Cluster analysis of the four index scores (i.e., Verbal Comprehension [VCI], Perceptual Organization [POI], Working Memory [WMI], Processing Speed [PSI]) identified six profiles in this sample. Profiles were differentiated by pattern of performance and were primarily characterized as (a) high VCI/POI, low WMI/PSI, (b) low VCI/POI, high WMI/PSI, (c) high PSI, (d) low PSI, (e) high VCI/WMI, low POI/PSI, and (f) low VCI, high POI. These profiles are potentially useful for determining whether a patient's WAIS-III performance is unusual in a normal population.

Canada↗

A clinical construct validity study of a novel computerized battery for the diagnosis of ADHD in young adults.

The cognitive profile of adult attention deficit hyperactivity disorder (ADHD) remains understudied despite difficulty in diagnosis. Further, no battery of neuropsychological tests has been shown valid in adult ADHD. Continuous performance tests are widely used for ADHD but provide limited information on cognitive functioning in general. The present study evaluated the construct and discriminant validity of Mindstreams (NeuroTrax Corp., NY), a computerized battery assessing multiple cognitive domains. Twenty-nine young male adults with ADHD diagnosis completed a Mindstreams battery, including a multi-stage continuous performance ('Expanded Go-NoGo') test, and the Conners' CPT-II (Multi-Health Systems Inc., NY). Discriminant validity was assessed by comparisons with cognitively healthy controls of comparable age and education. Expanded Go-NoGo and corresponding CPT-II outcomes were significantly correlated in ADHD participants, and the Expanded Go-NoGo test exhibited excellent discriminant validity, with ADHD participants performing more poorly than controls. ADHD participants also performed more poorly on Stroop and Staged Information Processing Speed tests.

Adult↗

Word list generation performance in Alzheimer's disease and vascular dementia.

Word list generation (WLG) was examined among clinical samples of individuals with Alzheimer's disease (AD) (n = 73) or ischemic vascular dementia (IVD) (n = 85), equivalent in age, education, current and estimated premorbid intellectual functioning, and proportion of men and women. The AD group performed significantly better than did the IVD group on lexical WLG, and a trend was observed indicating superior performance among the IVD group on categorical WLG. Within-groups, comparisons of group means, and profile analyses of individual performance patterns all indicated that persons with AD demonstrated a lexical > categorical pattern significantly more often than did IVD participants. The absolute difference in average performance between the AD and IVD groups on lexical and categorical WLG was small; the findings, however, generally support the clinical utility of the lexical > categorical WLG pattern in the differential diagnosis of AD and IVD. The patterns of performance support the presence of relative impairment in semantic processing among the individuals with AD and global deficits in retrieval and processing speed in individuals with IVD.

Aged↗

Sensitivity of computerized neuropsychological screening in depressed university students.

This study examined the sensitivity of a computerized neuropsychological screening (ImPACT) to the cognitive effects of depression in a sample of 20 students with suspected depression and 20 healthy university students matched for gender, age, and education. Students with depression had slower reaction times (p < .02; d = .82, large effect) and processing speeds (p < .03; d = .77, large effect). The brevity and sensitivity of ImPACT to the cognitive effects of depression warrants further research with psychiatric populations.

Adolescent↗

Does cognitive function in older adults with hearing impairment improve by hearing aid use?

In the present study, the effects of hearing aid use by hearing-impaired older individuals on different aspects of cognitive function, such as memory, attention, executive functioning, and processing speed, were investigated. Fifty-six participants (mean age = 72.5) who were fitted with hearing aids were compared with 46 control participants (mean age = 74.5) with an equivalent hearing impairment, but who were not fitted with a hearing aid. After a dual baseline measurement and fitting of the hearing aids, all participants were assessed again with neurocognitive tests after 12 months. While the participants with hearing aids had improved aided hearing thresholds, they did not demonstrate an improved performance on the cognitive tests compared to the controls. Thus improved hearing did not improve cognitive functioning. These findings may suggest that hearing aid use only restores impairments at the level of the sensory organ, but does not affect the central nervous system and, as a consequence, cognitive functioning.

Aged↗

Haptic memory and handedness in 2-month-old infants.

This study examined the robustness of infant haptic memory, asymmetry between hands, and sex differences in haptic memory in infancy. A total of 96 2-month-old infants (half males, half females) were habituated haptically to an object with their right and their left hand, out of the field of view. Haptic memory was then tested under three conditions: after haptic interference, after a 30-second delay, or after no delay. The results show that haptic habituation occurred for both hands. The girls needed more time to habituate with their left hand than with their right hand, and they habituated more slowly than the boys did. Discrimination was also found in both hands and in both sexes. Haptic delayed recognition memory was only found in young boys mainly after a short delay and under certain conditions after interference. In young girls, recognition memory was found after interference only with the left hand. This result seemed to depend on the information processing speed. Thus, for memory performance, a sex difference was clearly observed. Moreover, the infants' left hand retained better information on object shape than did the right hand for both the sexes. Asymmetries in infancy are discussed in connection with the difference in brain maturation rate.

Journal Article↗

Cognitive functioning in young people with first episode psychosis: relationship to diagnosis and clinical characteristics.

OBJECTIVE: To examine the extent and nature of neuropsychological deficits in adolescents and young people with first episode psychosis (FEP), and to determine whether the pattern and extent of neuropsychological deficits varied according to diagnosis. METHOD: A total of 83 FEP subjects aged 13-25 years, and 31 healthy controls completed a comprehensive battery of neuropsychological tests, grouped into 10 cognitive domains. First episode psychosis subjects were stratified into three diagnostic groups (schizophrenia, affective disorders, substance-induced psychosis) and differences in cognitive profiles were examined. The contribution of demographic and clinical characteristics to cognitive performance was also explored. RESULTS: The schizophrenia group demonstrated significantly worse performance on tasks of verbal learning and memory than the affective disorders group. Compared to healthy controls, the schizophrenia group also demonstrated global impairment across the majority of cognitive domains. The substance-induced group's performance lay between that of the schizophrenia and affective disorders groups. Analyses of differential deficits revealed that verbal learning, verbal memory and current intellectual functioning were selectively impaired in the schizophrenia group, whereas the affective disorders group demonstrated a selective deficit in speeded processing. Premorbid intellectual functioning, negative symptomatology and medication levels were the strongest predictors of cognitive performance in FEP subjects. CONCLUSIONS: Verbal memory deficits differentiate individuals with schizophrenia from those with psychotic affective disorders. Although significant cognitive deficits are evident across all diagnostic FEP groups, individuals with schizophrenia appear to have more generalized impairment across a broad array of cognitive functions than other psychotic diagnoses. Lower premorbid intellectual functioning does not appear to contribute to greater cognitive deterioration following onset of psychosis, but severity of illness may be a more important factor than levels of mood disturbance.

Adolescent↗

Validity of demographically corrected norms for the WAIS-III.

The diagnostic validity of new demographically corrected WAIS-III norms was investigated using a sample of 100 patients with traumatic brain injury (TBI) and a matched control group from the standardization sample. Demographically corrected norms were compared to traditional age-corrected norms. Although education accounted for incremental variance in WAIS-III factor scores in patients with TBI, above and beyond the effects of injury severity, the demographically corrected norms did not yield statistically different diagnostic classification of individuals with moderate-severe TBI than the traditional norms. In participants with relatively low levels of educational attainment, sensitivity to length of coma was less for demographically corrected norms then for traditional age-corrected norms. Nevertheless, when using a discrepancy between Verbal Comprehension and Processing speed, diagnostic accuracy rates were again similar for both sets of norms. It is concluded that the demographically corrected WAIS-III norms do not offer a clear advantage or disadvantage compared to traditional age-corrected norms in the assessment of patients with TBI who are Caucasian and who have at least a middle school level of education.

Adolescent↗

Use of an in-field-of-view shield to improve count rate performance of the single crystal layer high-resolution research tomograph PET scanner for small animal brain scans.

The count rate performance of the single LSO crystal layer high-resolution research tomograph (HRRT-S) PET scanner is limited by the processing speed of its electronics. Therefore, the feasibility of using an in-field-of-view (in-FOV) shield to improve the noise equivalent count rates (NECR) for small animal brain studies was investigated. The in-FOV shield consists of a lead tube of 12 cm length, 6 cm inner diameter and 9 mm wall thickness. It is large enough to shield the activity in the body of a rat or mouse. First, the effect of this shield on NECR was studied. Secondly, a number of experiments were performed to assess the effects of the shield on the accuracy of transmission scan data and, next, on reconstructed activity distribution in the brain. For activities below 150 MBq NECR improved only by 5-10%. For higher activities NECR maxima of 1.2E4 cps at 200 MBq and 2.2E4 cps at 370 MBq were found without and with shield, respectively. Listmode data taken without shield, however, were corrupted for activities above 75 MBq due to data overrun problems (time tag losses) of the electronics. When the shield was used data overrun was avoided up to activities of 150 MBq. For the unshielded part of the phantom, transmission scan data were the same with and without shield. The estimated scatter contribution was approximately 8.5% without and 5.5% with shield. Reconstructed emission data showed a difference up to 5% in the unshielded part of the phantom at 5 mm or more from the edge of the shielding. Of this 5% about 3% results from the difference in the uncorrected scatter contribution. In conclusion, an in-FOV shield can be used successfully in an HRRT PET scanner to improve NECR and accuracy of small animal brain studies. The latter is especially important when high activities are required for tracers with low brain uptake or when multiple animals are scanned simultaneously.

Animals↗

Classification of movement intention by spatially filtered electromagnetic inverse solutions.

We couple standardized low-resolution electromagnetic tomography, an inverse solution for electroencephalography (EEG) and the common spatial pattern, which is here conceived as a data-driven beamformer, to classify the benchmark BCI (brain-computer interface) competition 2003, data set IV. The data set is from an experiment where a subject performed a self-paced left and right finger tapping task. Available for analysis are 314 training trials whereas 100 unlabelled test trials have to be classified. The EEG data from 28 electrodes comprise the recording of the 500 ms before the actual finger movements, hence represent uniquely the left and right finger movement intention. Despite our use of an untrained classifier, and our extraction of only one attribute per class, our method yields accuracy similar to the winners of the competition for this data set. The distinct advantages of the approach presented here are the use of an untrained classifier and the processing speed, which make the method suitable for actual BCI applications. The proposed method is favourable over existing classification methods based on an EEG inverse solution, which rely either on iterative algorithms for single-trial independent component analysis or on trained classifiers.

Algorithms↗

Hypothyroidism and cognition: preliminary evidence for a specific defect in memory.

The effect(s) of hypothyroidism on adult brain cognitive function are poorly understood. We performed a series of neuropsychological tests in 13 thyroid cancer patients while they continued to take their usual dose of levothyroxine (LT4) and again after discontinuing thyroid hormone. Three euthyroid subjects were also tested twice to assess the effect of repeated testing on performance. The tests assessed memory, mood, and attentional resources and controlled for the practice effects of repeated testing. The mean thyrotropin (TSH) on LT4 was 0.56 +/- 0.76 mU/L and while hypothyroid was 69 +/- 33 mU/L. While hypothyroid, the mean Beck depression score was significantly higher (15.31 +/- 9.41 hypothyroid vs. 7.31 +/- 4.82 on LT4) and the subjects rated themselves worse relative to functional memory, concentration, thinking, alertness, and motivation. Hypothyroidism was associated with a decrease in retrieval from memory (p = 0.0034), and this effect could not be attributed to depression or to practice effects. Thyroid state did not affect immediate recall, verbal learning, inhibitory efficiency, information processing speed, or attention switching. Athyrosis is associated with a decrement in delayed recall of verbal information but not in other objective measures of cognition, suggesting that the memory decrement of hypothyroidism is not caused by a generalized reduction in attentional resources.

Adult↗

Comparison of basic elements of human performance scores between urologists with various extents of experience.

BACKGROUND AND PURPOSE: An objective evaluation of innate ability and its ability to predict potential success as a surgical trainee is an appealing concept for the selection process of residency applications. The objective of this study was to evaluate whether basic elements of performance (BEP) could discriminate among resident applicants and urologists with various extents of surgical experience. SUBJECTS AND METHODS: One hundred forty-five participants were divided into four study groups: group A, 57 urology residency applicants to the 2002 and 2003 interview process; group B, 8 post-internship urology residents; group C, 19 urologists tested with BEP within 10 years of graduation from their residency training program; and group D, 61 urologists who had graduated from their residency training program more than 10 years prior to testing. The BEP measures consisted of 13 basic performance resources (BPR) including visual-information processing speed, visual-spatial immediate-recall capacity, and neuromotor channel capacity. RESULTS: The four study groups differed significantly in their mean age: group A=27.6 years, group B=29.1 years, group C=37.1 years, and group D=48.9 years (P<0.0005). There was essentially no significant difference between the groups with regard to immediate-recall memory, reaction time simple, or reaction time complicated. The younger participants (groups A and B) were faster than the older surgeons (groups C and D) (P<0.02). However, the older surgeons (groups C and D) were significantly more accurate than the younger groups (A and B) (P<0.0005). The only sex differences noted were in hand-grip strength and shoulder-strength scores, which were all higher in the men. CONCLUSIONS: There generally appears to be a lack of direct correlation between innate abilities and surgical experience. Urology resident applicants with no surgical experience and urology residents with limited surgical experience are faster but less accurate in innate skills testing than experienced practicing urologists.

Adult↗

Neurobehavioral outcome of closed head injury: implications for clinical trials.

This review encompasses the neurobehavioral sequelae of moderate to severe closed head injury (CHI). Following a discussion of posttraumatic amnesia and its measurement, the paper discusses assessment of the global outcome of CHI using the Glasgow Outcome Scale. Domains of residual neurobehavioral sequelae that are reviewed include attention/information processing speed, memory, language, intellectual ability, executive functions, and motor speed. The contribution of behavioral disturbance and psychosocial maladjustment to overall outcome is reviewed, as is the impact on the family. Finally, the neurobehavioral outcome measures for clinical trials involving moderate to severe head-injured patients are presented. Caveats for completing clinical trials that involve assessment of neurobehavioral functioning are provided.

Adult↗