The CLOX is a clock drawing test used to screen for cognitive impairment in older adults, but there is limited normative data for this measure. This study presents normative data for the CLOX derived from a diverse sample of 585 community-dwelling older adults with complete cognitive data at baseline and 4-year follow-up. Participants with evidence of baseline impairment or substantial 4-year decline on the Mini-Mental State Examination were excluded from the normative sample. Spontaneous clock drawing (CLOX1) and copy (CLOX2) performances were stratified by age group and reading ability from the Wide Range Achievement Test, 3rd edition (WRAT-3). Lowest mean CLOX scores were observed for the oldest age group (75+ years old) with the lowest WRAT-3 reading scores. For all groups, average scores were higher for CLOX2 than CLOX1. These normative data may be helpful to clinicians and researchers for interpreting CLOX performance in older adults with diverse levels of reading ability.
Normative data; Clock drawing test; Reading ability; Older adults; Aging
Research in Attention-Deficit/Hyperactivity Disorder (ADHD) generally utilizes clinical samples or children with comorbid psychiatric diagnoses. Findings indicated that children with ADHD experience academic underachievement and poor performance on measures of response inhibition (RI). Less is known, about the neuropsychological profile of typically developing children with ADHD. The aim of the current study was twofold: (1) determine if academic skills and RI were impaired in typically developing children with ADHD-combined subtype (ADHD-C) and (2) determine to what extent RI may predict academic abilities. Children with ADHD-C did not differ on any academic domain from controls. Children with ADHD-C performed more poorly than controls on RI measures. Regression analyses suggest that Written Expression ability was significantly influenced by RI. No other academic domain was related to RI. Results suggest that children with ADHD-C may experience impairments in RI despite adequate academic functioning. Impaired RI is not solely responsible for difficulties found in academic skills in ADHD-C.
ADHD; Achievement; Executive functions; Response inhibition
The majority of research on neurobehavioral functioning among children with Attention-Deficit/Hyperactivity Disorder (ADHD) is based on samples comprised primarily (or exclusively) of boys. Although functional impairment is well established, available research has yet to specify a neuropsychological profile distinct to girls with ADHD. The purpose of this study was to examine performance within four components of executive function (EF) in contemporaneously recruited samples of girls and boys with ADHD. Fifty-six children with ADHD (26 girls) and 90 controls (42 girls), ages 8–13, were administered neuropsychological tests emphasizing response inhibition, response preparation, working memory, and planning/shifting. There were no significant differences in age or SES between boys or girls with ADHD or their sex-matched controls; ADHD subtype distribution did not differ by sex. Compared with controls, children with ADHD showed significant deficits on all four EF components. Girls and boys with ADHD showed similar patterns of deficit on tasks involving response preparation and working memory; however, they manifested different patterns of executive dysfunction on tasks related to response inhibition and planning. Girls with ADHD showed elevated motor overflow, while boys with ADHD showed greater impairment during conscious, effortful response inhibition. Girls, but not boys with ADHD, showed impairment in planning. There were no differences between ADHD subtypes on any EF component. These findings highlight the importance of studying boys and girls separately (as well as together) when considering manifestations of executive dysfunction in ADHD.
Attention; Response control; Working memory; Inhibition; Planning; Childhood; Development
The Dementia Rating Scale (DRS) is a widely used measure of global cognition, with age- and education-corrected norms derived from a cross-sectional sample of adults participating in Mayo's Older Americans Normative Studies (MOANS). In recent years, however, studies have indicated that cross-sectional normative samples of older adults represent an admixture of individuals who are indeed cognitively normal (i.e., disease-free) and individuals with incipient neurodegenerative disease. Theoretically, the “contamination” of cross-sectional normative samples with cases of preclinical dementia can lead to underestimation of the test mean and overestimation of the variance, thus reducing the clinical utility of the norms. Robust norming, in which dementia cases are removed from the normative cohort through longitudinal follow-up, is an alternative approach to norm development. The current study presents a reappraisal of the original MOANS DRS norms, provides robust and expanded norms based on a sample of 894 adults age 55 and over, and critically evaluates the benefits of robust norming.
Dementia Rating Scale; DRS; Alzheimer's disease; Robust; Norms
Differences in the memory characteristics of patients with Alzheimer's disease (AD), Huntington's disease (HD), and Parkinson's disease (PD) were investigated with tests that assess learning and retention of words, line-drawn objects, and locations. Large groups of AD, HD, and PD patients were administered the Hopkins Verbal Learning Test-Revised (HVLT-R) and the Hopkins Board (HB). Eight learning and memory measures were subjected to discriminant function analysis. A 91% classification accuracy was achieved for the separation of cortical and subcortical dementias and 79% accuracy for the discrimination of the three groups. The delayed recall of items was the best discriminator. Receiver-operating curve analysis indicated up to 90% sensitivity and 90% specificity in differentiating the three diseases using the discriminant scores. Individual learning and memory measures of the HVLT-R and the HB provided very high sensitivity and specificity in distinguishing cortical versus subcortical dementias and modest accuracy in separating the two subcortical diseases.
Episodic memory; Alzheimer's disease; Huntington's disease; Parkinson's disease
The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) has demonstrated adequate sensitivity in detecting cognitive impairment in a number of neuropsychiatric conditions, including Alzheimer's disease. However, its ability to detect milder cognitive deficits in the elderly has not been examined. The current study examined the clinical utility of the RBANS by comparing two groups: Patients with Mild Cognitive Impairment (MCI; n = 72) and cognitively intact peers (n = 71). Significant differences were observed on the RBANS Total score, 3 of the 5 Indexes, and 6 of the 12 subtests, with individuals with MCI performing worse than the comparison participants. Specificity was very good, but sensitivity ranged from poor to moderate. Areas under the receiver operating characteristic curves for the RBANS Immediate and Delayed Memory Indexes and the Total Scale score were adequate. Although significant differences were observed between groups and the areas under the curves were adequate, the lower sensitivity values of the RBANS suggests that caution should be used when diagnosing conditions such as MCI.
Mild Cognitive Impairment; Diagnostic accuracy; Repeatable Battery for the Assessment of Neuropsychological Status
In the 19th century, Hughlings Jackson relied on clinical history, seizure semiology, and the neurologic examination as methods for seizure localization to inform the first epilepsy surgeries. In the 20th century, psychological and neuropsychological tests were first employed as both diagnostic and prognostic measures. The contemporary practice of epilepsy evaluation and management includes neuropsychology as a critical component of epilepsy care and research, and epilepsy and neuropsychology have enjoyed a very special and synergistic relationship. This paper reviews how epilepsy has shaped the practice of neuropsychology as a clinical service by asking critical questions that only neuropsychologists were in a position to answer, and how clinical care of epilepsy patients has been significantly improved based on neuropsychology's unique contributions.
The oral version of the Trail Making Test (OTMT) is a neuropsychological measure that provides an assessment of sequential set-shifting without the motor and visual demands of the written TMT (WTMT). Originally purposed to serve as an oral analog of the WTMT, the OTMT provides a means to evaluate patients with physical restrictions. However, formal validity studies and available normative data remain sparse. In a sample of healthy adults (n = 81), a strong correlation was observed between OTMT-B and its written counterpart (r = .62), but the correlations were weak between OTMT-A and either written version of the TMT. OTMT-B was significantly correlated with age but not with education or gender, whereas OTMT-A was not significantly correlated with demographic factors. The WTMT to OTMT ratios observed in the current study were generally lower than previously reported and varied across age groups, suggesting that the recommended use of a uniform conversion factor to predict one performance based on the other should be cautiously undertaken. Normative data that have been stratified by age are provided as well as suggestions for using both versions of the TMT in tandem to better elucidate the nature of cognitive deficits and to aid in the localization of cerebral dysfunction.
Neuropsychology; Normative data; Cognitive tests; Trail Making Tests; Neuropsychological assessment
Attention deficit hyperactivity disorder (ADHD) is associated with deficits in executive functioning (EF). ADHD in adults is also associated with impairments in major life activities, particularly occupational functioning. We investigated the extent to which EF deficits assessed by both tests and self-ratings contributed to the degree of impairment in 11 measures involving self-reported occupational problems, employer reported workplace adjustment, and clinician rated occupational adjustment. Three groups of adults were recruited as a function of their severity of ADHD: ADHD diagnosis (n = 146), clinical controls self-referring for ADHD but not diagnosed with it (n = 97), and community controls (n = 109). Groups were combined and regression analyses revealed that self-ratings of EF were significantly predictive of impairments in all 11 measures of occupational adjustment. Although several tests of EF also did so, they contributed substantially less than did the EF ratings, particularly when analyzed jointly with the ratings. We conclude that EF deficits contribute to the impairments in occupational functioning that occur in conjunction with adult ADHD. Ratings of EF in daily life contribute more to such impairments than do EF tests, perhaps because, as we hypothesize, each assesses a different level in the hierarchical organization of EF as a meta-construct.
Adult ADHD; Executive functioning (EF); EF ratings; EF tests; Occupational impairment
Assessing cognitive change in older adults is a common use of neuropsychological services, and neuropsychologists have utilized several strategies to determine if a change is “real,” “reliable,” and “meaningful.” Although standardized regression-based (SRB) prediction formulas may be useful in determining change, SRBs have not been widely applied to older adults. The current study sought to develop SRB formulas on a group of 127 community-dwelling older adults for several widely used neuropsychological measures. In addition to baseline test scores and demographic information, the current study also examined the role of short-term practice effects in predicting test scores after 1 year. Consistent with prior research on younger adults, baseline test performances were the strongest predictors of future test performances, accounting for 25%–58% of the variance. Short-term practice effects significantly added to the predictability of all nine of the cognitive tests examined (3%–22%). Future studies should continue extending SRB methodology for older adults, and the inclusion of practice effects appears to add to the prediction of future cognition.
Predicting cognition; Practice effects
Diabetes is associated with dementia in older adults, but it remains unclear whether nondemented adults with type 2 diabetes show subtle abnormalities across cognition, neuroanatomy, and everyday functioning. Using the Aging, Brain Imaging, and Cognition study sample of 301 community-dwelling, middle-aged and older adults, we conducted a secondary analysis on 28 participants with and 150 participants without diabetes. We analyzed brain magnetic resonance imaging data, cognitive test performance, and informant ratings of personal and instrumental activities of daily living (PADL/IADL). Relative to controls, participants with diabetes had lower brain-to-intracranial volume ratios (69.3 ± 4.5% vs. 71.7 ± 4.6%; p < .02), and performed more poorly on measures of working memory, processing speed, fluency, and crystallized intelligence (all p <.05). Decrements in working memory and processing speed were associated with IADL limitations (p < .01). Nondemented adults with diabetes exhibit neuroanatomic and cognitive abnormalities. Their cognitive deficits correlate with everyday functional limitations.
Diabetes; Endocrine disorders; Cognition; Neuropsychological testing; MRI; Function; Behavior
HIV+ individuals have been shown to demonstrate deficits on the Iowa Gambling Task (IGT), a complex measure of “decision-making.” Little remains known about what other neurocognitive processes may account for variability in IGT performance among HIV+ samples or the role of procedural learning (PL) in IGT performance. A sample of 49 HIV+ individuals with a history of substance use disorders was examined to explore the relationship between IGT performance and three measures of PL: The Rotary Pursuit, Mirror Star Tracing, and Weather Prediction tasks. We found no statistically significant relationships between IGT performance and any of the PL tasks, despite finding significant correlations among the PL tasks. This pattern of results persisted when analyzing IGT performance in various ways (e.g., performance on earlier trial blocks or impairment classifications). Although other nondeclarative processes (e.g., somatic markers) may be important for IGT performance, these findings do not support PL as an important component neurocognitive process for the IGT. Similarly, these results suggest that differences in PL performance does not account for the decision-making deficits or variability in performances observed on the IGT among HIV+ individuals with a history of substance dependence.
HIV; Substance use disorders; Nondeclarative memory; Implicit memory; Decision-making; Basal ganglia; Orbitofrontal cortex; Executive functions
The n-back is a putative working memory task frequently used in neuroimaging research; however, literature addressing n-back use in clinical neuropsychological evaluation is sparse. We examined convergent validity of the n-back with an established measure of working memory, digit span backward. The relationship between n-back performance and scores on measures of processing speed was also examined, as was the ability of the n-back to detect potential between-groups differences in control and Parkinson's disease (PD) groups. Results revealed no correlation between n-back performance and digit span backward. N-back accuracy significantly correlated with a measure of processing speed (Trail Making Test Part A) at the 2-back load. Relative to controls, PD patients performed less accurately on the n-back and showed a trend toward slower reaction times, but did not differ on any of the neuropsychological measures. Results suggest the n-back is not a pure measure of working memory, but may be able to detect subtle differences in cognitive functioning between PD patients and controls.
Working memory; Executive function; Information processing speed; Parkinson's disease; Neuropsychology
Recent studies have shown that self-perceived health status (HS) in Parkinson's disease (PD) is associated with motor, cognitive, or mood symptoms, with the greatest association typically occurring with mood. The purpose of this study was to determine if these associations are present in nondepressed and nondemented individuals with PD by using sensitive neuropsychological measures and statistically derived factors from mood and motor scales. The best predictors of poor HS in PD participants (N = 32) without dementia or depression were mood symptoms, specific to self-reported cognitive impairment and anxiety. Bivariate correlations between HS and number of correct categories on the Wisconsin Card Sorting Test and the gait–balance factor from the Unified Parkinson's Disease Rating Scale Part III were also significant or approached significance. These findings suggest that specific mood and cognitive symptoms continue to be important factors in HS in those individuals who lack clinical levels of depression or dementia.
Parkinson's disease; Health status; Health-related quality of life; Quality of life
Memory assessment is an important component of a neuropsychological evaluation, but far fewer visual than verbal memory instruments are available. We examined the preliminary psychometric properties and clinical utility of a novel, motor-free paper and pencil visuospatial memory test, the Indiana faces in places test (IFIPT). The IFIPT and general neuropsychological performance were assessed in 36 adults with amnestic mild cognitive impairment (aMCI) and 113 older adults with no cognitive impairment at baseline, 1 week, and 1 year. The IFIPT is a visual memory test with 10 faces paired with spatial locations (three learning trials and non-cued delayed recall). Results showed that MCI participants scored lower than controls on several variables, most notably total learning (p < .001 at all three time points), delayed recall (baseline p = .03, 1 week p < .001, 1 year p < .001), and false-positive errors (range p = .03 to <0.001). The IFIPT showed similar test–retest reliability at 1-week and 1-year follow-up to other neuropsychological tests (r = 0.71–0.84 for MCI and 0.53–0.72 for controls). Diagnostic accuracy was modest for this sample (areas under the receiver operating characteristic curve between 0.64 and 0.66). Preliminary psychometric analyses support further study of the IFIPT. The measure showed evidence of clinical utility by demonstrating group differences between this sample of healthy adults and those with MCI.
Mild cognitive impairment; Visual memory; Face memory; Test–retest reliability
Prospective memory is defined as the ability to “remember to remember” something at a future time despite intervening distractions and may be particularly important in remembering to take prescribed medication among people infected with HIV. Ninety-seven HIV-positive participants in a clinical trial had their adherence measured by electronic pillcaps and were administered neuropsychological screening tests and the memory for intentions screening test (MIST). Factor analysis of the MIST and other neuropsychological measures identified four factors. Two were derived from MIST subscales and accounted for approximately 50% of the variance in cognitive functioning. Only one factor was significantly correlated with adherence, and this was a MIST factor. In this preliminary study, the MIST assessed a memory function that (a) could be distinguished from traditional retrospective recall and executive functioning and (b) was correlated with antiretroviral adherence.
HIV; Neuropsychological function; Adherence; Medication compliance; Substance use
This study examined the sensitivity of diffusion tensor imaging (DTI) to microstructural white matter (WM) damage in mild and moderate pediatric traumatic brain injury (TBI). Fourteen children with TBI and 14 controls ages 10–18 had DTI scans and neurocognitive evaluations at 6–12 months post-injury. Groups did not differ in intelligence, but children with TBI showed slower processing speed, working memory and executive deficits, and greater behavioral dysregulation. The TBI group had lower fractional anisotropy (FA) in three WM regions: inferior frontal, superior frontal, and supracallosal. There were no group differences in corpus callosum. FA in the frontal and supracallosal regions was correlated with executive functioning. Supracallosal FA was also correlated with motor speed. Behavior ratings showed correlations with supracallosal FA. Parent-reported executive deficits were inversely correlated with FA. Results suggest that DTI measures are sensitive to long-term WM changes and associated with cognitive functioning following pediatric TBI.
Traumatic brain injury (TBI); Diffusion tensor imaging (DTI); White matter; Pediatric
The goals of this project were threefold: to determine the nature of the memory deficit in children/adolescents with dyslexia, to utilize clinical memory measures in this endeavor, and to determine the extent to which semantic short-term memory (STM) is related to basic reading performance. Two studies were conducted using different samples, one incorporating the Wide Range Assessment of Memory and Learning and the other incorporating the California Verbal Learning Test-Children's Version. Results suggest that phonological STM is deficient in children with dyslexia, but semantic STM and visual–spatial STM are intact. Long-term memory (LTM) for both visual and verbal material also is intact. Regarding reading performance, semantic STM had small correlations with word identification and pseudoword decoding across studies despite phonological STM being moderately to strongly related to both basic reading skills. Overall, results are consistent with the phonological core deficit model of dyslexia as only phonological STM was affected in dyslexia and related to basic reading skill.
Dyslexia; Reading disabilities; Child; Adolescent; Short-term memory; Long-term memory
Deficits in learning, memory, and executive functions are common cognitive sequelae of Parkinson's disease with dementia (PDD) and Alzheimer's disease (AD); however, the pattern of deficits within these populations is distinct. Hierarchical regression was used to investigate the contribution of two measures with executive function properties (Verbal Fluency and CLOX) on list-learning performance (CVLT-II total words learned) in a sample of 25 PDD patients and 25 matched AD patients. Executive measures were predictive of list learning in the PDD group after the contribution of overall cognition and contextual verbal learning was accounted for, whereas in the AD group the addition of executive measures did not add to prediction of variance in CVLT-II learning. These findings suggest that deficits in executive functions play a vital role in learning impairments in patients with PDD; however, for AD patients, learning difficulties appear relatively independent of executive dysfunction.
Parkinson's disease with dementia; Alzheimer's disease; Executive function; List learning; Neuropsychologic tests; Comparative studies
White matter hyperintensities (WMH) can compromise cognition in older adults, but differences in sampling, WMH measurements, and cognitive assessments contribute to discrepant findings across studies. We examined linear and nonlinear effects of WMH volumes on cognition in 253 reasonably healthy adults. After adjusting for demographic characteristics and total brain volumes, WMH burden was not associated with cognition in those aged 20–59. In participants aged 60 and older, models accounted for ≥58% of the variance in performance on tests of working memory, processing speed, fluency, and fluid intelligence, and WMH volumes accounted for variance beyond that explained by age and other demographic characteristics. Larger increases in WMH burden over 5 years also were associated with steeper cognitive declines over the same interval. Results point to both age-related and age-independent effects of WMH on cognition in later life and suggest that the accumulation of WMH might partially explain normal age-related declines in cognition.
White matter hyperintensities; Aging; Cognition; Cardiovascular disease
Self-report post-concussion symptom scales have been a key method for monitoring recovery from sport-related concussion, to assist in medical management, and return-to-play decision-making. To date, however, item selection and scaling metrics for these instruments have been based solely upon clinical judgment, and no one scale has been identified as the “gold standard”. We analyzed a large set of data from existing scales obtained from three separate case–control studies in order to derive a sensitive and efficient scale for this application by eliminating items that were found to be insensitive to concussion. Baseline data from symptom checklists including a total of 27 symptom variables were collected from a total of 16,350 high school and college athletes. Follow-up data were obtained from 641 athletes who subsequently incurred a concussion. Symptom checklists were administered at baseline (preseason), immediately post-concussion, post-game, and at 1, 3, and 5 days post-injury. Effect-size analyses resulted in the retention of only 12 of the 27 variables. Receiver-operating characteristic analyses were used to confirm that the reduction in items did not reduce sensitivity or specificity. The newly derived Concussion Symptom Inventory is presented and recommended as a research and clinical tool for monitoring recovery from sport-related concussion.
Brain injury; Post-concussion; Scale
Beyond the Numbers: Expanding the Boundaries of Neuropsychology was Dr Perry's 2007 presidential address in the annual conference of the National Academy of Neuropsychology. In his address he discussed the achievements of the science of neuropsychology and highlighted some areas that exemplified the expansion of the boundaries of neuropsychology. These areas are: (i) the study of neuropsychological functioning in new or non-traditional populations, particularly seemingly healthy people and people with non-brain diseases; (ii) the interface of cognition and genetics; (iii) the use of the process approach as a means of understanding brain functioning; and (iv) a translational application to the science of neuropsychology.
Neuropsychology; Translational research; Process approach; Genetics; Deconstruction
Dementia screening batteries often fall short on measures of executive functioning. The Weigl Color Form Sorting Test (WCFST) is a candidate for inclusion in such batteries, but can be insensitive to mild disturbance. The WCFST consists of 12 colored geometric shapes and requires the patient to sort the pieces by color or form, and then shift to the other sorting principle unassisted. We created a modified version of the WCFST (the Weigl-R) with increased conceptual complexity by adding two stimulus dimensions (texture and central shapes). The range of scores was also increased by adding the extent of examiner assistance required to achieve a correct sort, ability to verbalize conceptual strategy, and number of perseverations. We administered the Weigl-R to a group of 30 patients with mixed dementias, 34 adults with cognitive impairment without dementia, and 21 healthy controls. The new measure discriminated well between healthy controls and older adults with either cognitive impairment without dementia, or dementia. The Weigl-R may be a useful adjunct to brief dementia batteries but requires further validation.
Dementia; Executive functioning; Neuropsychology; Conceptual reasoning
The purpose of this study was to examine the impact of age, sex, and education on category and letter verbal fluency task performance. A secondary goal was to examine whether resting EEG theta power in bilateral frontal and temporal lobes impacts age-associated decline in verbal fluency task performance. A large sample (N=471) of healthy, normal participants, age 21–82, was assessed for letter fluency (i.e., FAS), and for category fluency (i.e., Animal Naming), and with a 32-channel EEG system for ‘eyes-open’ resting theta power. The effects of age, sex, and education were examined using analyses of variance. Correlation analyses were used to test the impact of theta power on age and fluency performance by controlling for the effects of theta when examining the relationship between the other two variables. The results indicated that performance on both fluency tests declined linearly with age, but that the rate of decline was greater for category fluency. These age changes were not associated with education level, and there were no sex differences. While theta power was negatively associated with age and positively associated with Animal Naming performance, it did not moderate the relationship between the two. The differential age-associated decline between category and letter fluency suggests separate neurobiological substrates underlying the two domains of performance, which is not related to theta activity.
Normal aging; Category fluency; Letter fluency; EEG; Theta
The Clock Drawing Test (CDT) is a common neuropsychological measure sensitive to cognitive changes and functional skills (e.g., driving test performance) among older adults. However, normative data have not been adequately developed. We report the distribution of CDT scores using three common scoring systems (Mendez, Ala, and Underwood, 1992; Freund, Gravenstein, Ferris, Burke, & Shaheen, 2005; and Cahn, Salmon, Monsch, Butters, Wiederholt, & Corey-Bloom, 1996), among 207 cognitively normal elderly. The systems were well correlated, took little time to use, and had high inter-rater reliability. We found statistically significant differences in CDT scores based on age and WRAT-3 Reading score, a marker of education quality. We present means, standard deviations, and t- and z-scores based on these subgroups. We found that “normal” CDT performance includes a wider distribution of scores than previously reported. Our results may serve as useful comparisons for clinicians wishing to know whether their patients perform in the general range of cognitively normal elderly.
Clock Drawing Test; clock drawing; normal aging; normative data; scoring systems; neuropsychological tests; elderly; Alzheimer’s disease; mild cognitive impairment; dementia; cognitive decline; cognitive screening