Estimating premorbid intelligence in people living with dementia: a systematic review

OBJECTIVES

In diagnosing dementia, estimating premorbid functioning is critical for accurate detection of the presence and severity of cognitive decline. However, which assessments of premorbid intelligence are most suitable for use in clinical practice is not well established. Here, we systematically evaluate the validity of instruments for measuring premorbid intelligence in people living with dementia.

DESIGN AND SETTING

In this systematic review, electronic databases (EMBASE, PsycINFO, MEDLINE, CINAHL, and AMED) were searched to identify studies reporting on objective measures of premorbid intelligence in dementia. Participants from included studies were recruited from local communities and clinical settings.

PARTICIPANTS

A total of 1082 patients with dementia and 2587 healthy controls were included in the review.

MEASUREMENTS

The literature search resulted in 13 eligible studies describing 19 different instruments. The majority of instruments (n = 14) consisted of language-based measures, with versions of the National Adult Reading Test (NART) being most commonly investigated.

RESULTS

Preliminary evidence suggested comparable performance of patients with mild dementia and healthy controls on word reading tasks in English, Portuguese, Swedish, and Japanese. In moderate dementia, however, the performance was significantly impaired on most verbal tasks. There was a lack of reliability and validity testing of available instruments, with only one of the included studies reporting psychometric properties within the patient group.

CONCLUSIONS

The results demonstrate that there is a wide range of tools available for estimating premorbid intelligence in dementia, with cautious support for the potential of word reading tasks across different languages in individuals with mild dementia. However, the review highlights the urgent need for extensive assessments of the psychometric properties of these tasks in dementia. We propose that further longitudinal research and assessments of nonverbal measures are necessary to validate these instruments and enhance diagnostic procedures for people living with dementia worldwide.

A cohort study of neuropsychological functioning in spouses of U.S. Gulf War veterans

AIMS

Veterans of the 1991 Gulf War reported symptoms in their spouses that mirrored veterans' symptoms following their return from the war, including problems with attention and memory. Neuropsychological functioning in these spouses has not been examined with objective tests. This study sought to determine if these spouses exhibited deficits in neuropsychological functioning.

MAIN METHODS

Spouses of a national cohort of 1991 Gulf War deployed (n = 470) and non-deployed veterans (n = 524) were examined with neuropsychological tests in 1999-2001.

KEY FINDINGS

Neuropsychological tests were factor analyzed yielding five factors: verbal memory, visual memory, attention/working memory, visual organization, and motor speed. Spouses of deployed and nondeployed veterans did not differ on mean factor scores, percentage of impaired factors, or individual test scores. Spouse attention/working memory was related to their having diagnoses of PTSD or anxiety disorders, or self-reported symptoms of current anxiety. Spouse visual memory was related to a diagnosis of current depression. Spouse motor speed was related to their own status of having chronic multisymptom illness (CMI).

SIGNIFICANCE

Spouses of Gulf War deployed and nondeployed veterans demonstrated similar neuropsychological functioning, although spouses with psychiatric diagnoses and symptoms, or CMI demonstrated neuropsychological impairments characteristic of those conditions, suggesting that monitoring spouses for these conditions and impairments may be warranted. This pattern of relative weaknesses mirrors some of the previously reported findings for Gulf War veterans, although the veterans displayed neuropsychological impairments beyond what was accounted for by these conditions.

Cognitive performance is lower among individuals with overlap syndrome than in individuals with COPD or obstructive sleep apnea alone: association with carotid artery stiffness

Chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) are both independently associated with increased cardiovascular disease (CVD) risk and impaired cognitive function. It is unknown if individuals with both COPD and OSA (i.e., overlap syndrome) have greater common carotid artery (CCA) stiffness, an independent predictor of CVD risk, and lower cognitive performance than either COPD or OSA alone. Elevated CCA stiffness is associated with cognitive impairment in former smokers with and without COPD in past studies. We compared CCA stiffness and cognitive performance between former smokers with overlap syndrome, COPD only, OSA only and former smoker controls using analysis of covariance (ANCOVA) tests to adjust for age, sex, body mass index (BMI), pack years, and postbronchodilator FEV1/FVC. We also examined the association between CCA stiffness and cognitive performance among each group separately. Individuals with overlap syndrome (n = 12) had greater CCA β-stiffness index (P = 0.015) and lower executive function-processing speed (P = 0.019) than individuals with COPD alone (n = 47), OSA alone (n = 9), and former smoker controls (n = 21), differences that remained significant after adjusting for age, BMI, sex, pack years, and FEV1/FVC. Higher CCA β-stiffness index was associated with lower executive function-processing speed in individuals with overlap syndrome (r = -0.58, P = 0.047). These data suggest that CCA stiffness is greater and cognitive performance is lower among individuals with overlap syndrome compared with individuals with COPD or OSA alone and that CCA stiffening may be an underlying mechanism contributing to the lower cognitive performance observed in patients with overlap syndrome.NEW & NOTEWORTHY Previous studies have demonstrated greater carotid artery stiffness and lower cognitive function among individuals with COPD alone and OSA alone. However, the present study is the first to demonstrate that individuals that have both COPD and OSA (i.e., overlap syndrome) have greater carotid artery stiffness and lower executive function-processing speed than individuals with either disorder alone. Furthermore, among individuals with overlap syndrome greater carotid artery stiffness is associated with lower executive function-processing speed.

Multi-Paradigm fMRI Fusion via Sparse Tensor Decomposition in Brain Functional Connectivity Study

Functional magnetic resonance imaging (fMRI) is a powerful technique with the potential to estimate individual variations in behavioral and cognitive traits. Joint learning of multiple datasets can utilize their complementary information so as to improve learning performance, but it also gives rise to the challenge for data fusion to effectively integrate brain patterns elicited by multiple fMRI data. However, most of the current data fusion methods analyze each single dataset separately and further infer the relationship among them, which fail to utilize the multidimensional structure inherent across modalities and may ignore complex but important interactions. To address this issue, we propose a novel sparse tensor decomposition method to integrate multiple task-stimulus (paradigm) fMRI data. Seeing each paradigm fMRI as one modality, our proposed method considers the relationships across subjects and modalities simultaneously. In specific, a third-order tensor is first modeled by using the functional network connectivity (FNC) of subjects in multiple fMRI paradigms. A novel sparse tensor decomposition with the regularization terms is designed to factorize the tensor into a series of rank-one components, which can extract the shared components across modalities as the embedded features. The L2,1-norm regularizer (i.e., group sparsity) is enforced to select a few common features among multiple subjects. Validation of the proposed method is performed on realistic three paradigm fMRI datasets from the Philadelphia Neurodevelopmental Cohort (PNC) study, for the study of the relationship between the FNC and human cognitive abilities. Experimental results show our method outperforms several other competing methods in the prediction of individuals with different cognitive behaviors via the wide range achievement test (WRAT). Furthermore, our method discovers the FNC related to the cognitive behaviors, such as the connectivity associated with the default mode network (DMN) for three paradigms, and the connectivity between DMN and visual (VIS) domains within the emotion task.

Carotid Artery Stiffness is Associated With Cognitive Performance in Former Smokers With and Without Chronic Obstructive Pulmonary Disease

Background Heavy smokers perform worse on neuropsychological assessment than age-matched peers. However, traditional pulmonary measures of airflow limitation and hypoxemia explain only a modest amount of variance in cognition. The current objective was to determine whether carotid artery stiffness is associated with cognition in former smokers beyond the effects of amount of smoking and pulmonary function. Methods and Results Eighty-four former smokers including individuals across a spectrum of airflow limitation severity were included: 30 without chronic obstructive pulmonary disease (Global Initiative for Chronic Obstructive Lung Disease [GOLD] 0 with normal spirometry and lung computed tomography), 31 with mild-moderate chronic obstructive pulmonary disease (GOLD 1-2), and 23 with severe-very severe chronic obstructive pulmonary disease (GOLD 3-4). Participants completed questionnaires, spirometry, carotid ultrasonography, and neuropsychological testing. Multiple linear regression was used to determine whether carotid artery stiffness is associated with neuropsychological performance in 4 cognitive domains after adjusting for age, sex, pack-years of smoking, estimated premorbid intellectual functioning, and airflow limitation. Higher carotid artery β-stiffness index was associated with reduced executive functioning-processing speed in the fully adjusted model (β=-0.49, SE=0.14; P=0.001). Lower premorbid intellectual function, male sex, and presence of airflow limitation (GOLD 1 or 2 and GOLD 3 or 4) were also associated with worse executive functioning-processing speed. β-Stiffness index was not significantly associated with performance in other cognitive domains. Conclusions Carotid artery stiffness is associated with worse performance on executive functioning-processing speed in former smokers beyond the effects of aging, amount of past smoking, severity of airflow limitation, and hypoxemia. Future research should examine whether carotid stiffness can be used to identify former smokers at risk for subsequent cognitive impairment.

Examination of Regression-based Discrepancy Scores for the RBANS in Detecting Cognitive Impairment from an Archival Sample

OBJECTIVE

The purpose of this study was to evaluate the clinical utility of regression-based formulas for the RBANS indexes in screening for cognitive impairment.

METHOD

A database of neuropsychological test results was created from archival records in a memory assessment clinic. The sample consisted of 83 individuals (37 males/46 females) with an average age of 70.1 (SD = 9.8) and 14.6 years of education (SD = 2.8). Diagnostic accuracy of regression-based predictions provided by Duff and Ramezani (2015) (Duff, K., & Ramezani, A. (2015). Regression-based normative formulae for the Repeatable Battery for the Assessment of Neuropsychological Status for older adults. Archives of Clinical Neuropsychology, 30, 600-604.) and from regression of WTAR standard score were examined via receiver operator characteristic curves. Preliminary generalizability investigation was completed using two additional datasets.

RESULTS

The WTAR was found to mediate the relationship between education and all RBANS index scores. The WTAR standard score was also found to contribute uniquely and significantly to the prediction of RBANS performance. Results of diagnostic accuracy analyses showed similar discriminating accuracy for all scores. There was limited support for using the WTAR over demographic variables alone in the estimation of RBANS performance; however, the WTAR was found to be more predictive than education, indicating potential clinical utility to using the word-reading score over just years of attained education.

CONCLUSIONS

Use of these derived Total Scale score variants is recommended for the screening of cognitive impairment, particularly in individuals with superior or poor educational quality. Further research is required to evaluate the utility of these variations in more diverse samples.

An investigation of the use of standardised leaving certificate performance as a method of estimating pre-morbid intelligence

BACKGROUND

In cases of brain pathology, current levels of cognition can only be interpreted reliably relative to accurate estimations of pre-morbid functioning. Estimating levels of pre-morbid intelligence is, therefore, a crucial part of neuropsychological evaluation. However, current methods of estimation have proven problematic.

OBJECTIVE

To evaluate if standardised leaving certificate (LC) performance can predict intellectual functioning in a healthy cohort. The LC is the senior school examination in the Republic of Ireland, taken by almost 50 000 students annually, with total performance distilled into Central Applications Office points.

METHODS

A convenience sample of university students was recruited (n = 51), to provide their LC results and basic demographic information. Participants completed two cognitive tasks assessing current functioning (Vocabulary and Matrix Reasoning (MR) subtests - Wechsler Abbreviated Scale of Intelligence, Second Edition) and a test of pre-morbid intelligence (Spot-the-Word test from the Speed and Capacity of Language Processing). Separately, LC results were standardised relative to the population of test-takers, using a computer application designed specifically for this project.

RESULTS

Hierarchical regression analysis revealed that standardised LC performance [F(2,48) = 3.90, p = 0.03] and Spot-the-Word [F(2,47) = 5.88, p = 0.005] significantly predicted current intellect. Crawford & Allen's demographic-based regression formula did not. Furthermore, after controlling for gender, English [F(1,49) = 11.27, p = 0.002] and Irish [F(1,46) = 4.06, p = 0.049) results significantly predicted Vocabulary performance, while Mathematics results significantly predicted MR [F(1,49) = 8.80, p = 0.005].

CONCLUSIONS

These results suggest that standardised LC performance may represent a useful resource for clinicians when estimating pre-morbid intelligence.

Refined measure of functional connectomes for improved identifiability and prediction

Brain functional connectome analysis is commonly based on population-wise inference. However, in this way precious information provided at the individual subject level may be overlooked. Recently, several studies have shown that individual differences contribute strongly to the functional connectivity patterns. In particular, functional connectomes have been proven to offer a fingerprint measure, which can reliably identify a given individual from a pool of participants. In this work, we propose to refine the standard measure of individual functional connectomes using dictionary learning. More specifically, we rely on the assumption that each functional connectivity is dominated by stable group and individual factors. By subtracting population-wise contributions from connectivity patterns facilitated by dictionary representation, intersubject variability should be increased within the group. We validate our approach using several types of analyses. For example, we observe that refined connectivity profiles significantly increase subject-specific identifiability across functional magnetic resonance imaging (fMRI) session combinations. Besides, refined connectomes can also improve the prediction power for cognitive behaviors. In accordance with results from the literature, we find that individual distinctiveness is closely linked with differences in neurocognitive activity within the brain. In summary, our results indicate that individual connectivity analysis benefits from the group-wise inferences and refined connectomes are indeed desirable for brain mapping.

Premorbid IQ Predicts Postconcussive Symptoms in OEF/OIF/OND Veterans with mTBI

Objective

Extant literature has demonstrated that symptoms of postconcussive syndrome (PCS) persist well beyond the expected 3-month post-injury recovery period in a minority of individuals with mild traumatic brain injury (mTBI). Suboptimal performance on validity measures and pre- and post-injury psychosocial stressors - rather than actual mTBI or current cognitive functioning - have been identified as predictors of chronic PCS. Whether premorbid IQ has any influence on chronic PCS has been understudied, in the context of established psychogenic etiologies.

Method

The sample included 31 veterans, who underwent mTBI neuropsychological evaluations six or more months post-injury in a VA outpatient neuropsychology clinic. A two-step multiple linear regression was conducted to examine the effects on the outcome variable, PCS (Neurobehavioral Symptom Inventory), of the following predictors: cognitive functioning (Repeatable Battery for the Assessment of Neuropsychological Status; Attention, Immediate Memory, and Delayed Memory Indices), performance validity, depression (Beck Depression Inventory-Second Edition), posttraumatic stress disorder (PTSD Checklist, Civilian Version), quality of sleep (Pittsburgh Sleep Quality Index), pain (Brief Pain Inventory), education, and Premorbid IQ (Wechsler Test of Adult Reading).

Results

The overall regression model containing all nine predictor variables was statistically significant. Depression (p < .05) and premorbid IQ (p < .05) were the most salient predictors of chronic PCS; in that lower premorbid IQ and greater endorsed symptoms of depression were associated with higher PCS scores. In Step 2 of the multiple linear regression, the WTAR explained an additional 6.7% of the variance in PCS after controlling for psychosocial stressors and current cognitive ability.

Conclusion

The findings support premorbid IQ as a unique and relevant predictor of chronic PCS, with significance variance accounted for beyond education, cognitive functioning, and psychosocial variables. Given the predictive relationship between premorbid IQ and PCS, adapting postconcussive interventions to meet the specific needs of individuals with varying levels of intellect may be important in minimizing ongoing symptomatology.

Neuropsychological predictors of performance-based measures of functional capacity and social skills in individuals with severe mental illness

Neuropsychological abilities may underlie successful performance of everyday functioning and social skills. We aimed to determine the strongest neuropsychological predictors of performance-based functional capacity and social skills performance across the spectrum of severe mental illness (SMI). Unemployed outpatients with SMI (schizophrenia, bipolar disorder, or major depression; n = 151) were administered neuropsychological (expanded MATRICS Consensus Cognitive Battery), functional capacity (UCSD Performance-Based Skills Assessment-Brief; UPSA-B), and social skills (Social Skills Performance Assessment; SSPA) assessments. Bivariate correlations between neuropsychological performance and UPSA-B and SSPA total scores showed that most neuropsychological tests were significantly associated with each performance-based measure. Forward entry stepwise regression analyses were conducted entering education, diagnosis, symptom severity, and neuropsychological performance as predictors of functional capacity and social skills. Diagnosis, working memory, sustained attention, and category and letter fluency emerged as significant predictors of functional capacity, in a model that explained 43% of the variance. Negative symptoms, sustained attention, and letter fluency were significant predictors of social skill performance, in a model explaining 35% of the variance. Functional capacity is positively associated with neuropsychological functioning, but diagnosis remains strongly influential, with mood disorder participants outperforming those with psychosis. Social skill performance appears to be positively associated with sustained attention and verbal fluency regardless of diagnosis; however, negative symptom severity strongly predicts social skills performance. Improving neuropsychological functioning may improve psychosocial functioning in people with SMI.

The Social Attribution Task - Multiple Choice (SAT-MC): Psychometric comparison with social cognitive measures for schizophrenia research

The Social Attribution Task-Multiple Choice (SAT-MC) tests the ability to extract social themes from viewed object motion. This form of animacy perception is thought to aid the development of social inference, but appears impaired in schizophrenia. The current study was undertaken to examine psychometric equivalence of two forms of the SAT-MC and to compare their performance against social cognitive tests recommended for schizophrenia research. Thirty-two schizophrenia (SZ) and 30 substance use disorder (SUD) participants completed both SAT-MC forms, the Bell-Lysaker Emotion Recognition Task (BLERT), Hinting Task, The Awareness of Social Inference Test (TASIT), Ambiguous Intentions and Hostility Questionnaire (AIHQ) and questionnaire measures of interpersonal function. Test sensitivity, construct and external validity, test-retest reliability, and internal consistency were evaluated. SZ scored significantly lower than SUD on both SAT-MC forms, each classifying ~60% of SZ as impaired, compared with ~30% of SUD. SAT-MC forms demonstrated good test-retest and parallel form reliability, minimal practice effect, high internal consistency, and similar patterns of correlation with social cognitive and external validity measures. The SAT-MC compared favorably to recommended social cognitive tests across psychometric features and, with exception of TASIT, was most sensitive to impairment in schizophrenia when compared to a chronic substance use sample.

The Moderating Role of Insulin-Like Growth Factor 1 in the Relationship Between Cognitive and Aerobic Endurance Change

BACKGROUND

Improvements in cognition often accompany fitness improvements in older adults, and research suggests insulin-like growth factor 1 (IGF-1) may influence this association. No prior work has examined this in mild cognitive impairment (MCI). We predicted that IGF-1 would moderate the relationship between cognition and aerobic endurance improvement, such that greater baseline IGF-1 would accompany a stronger relationship between cognition and aerobic endurance change.

METHOD

Twenty-seven individuals with MCI completed assessments of aerobic endurance (2-minute step test [2MST]) and global cognition (Modified Mini-Mental State [3MS]) before and after a 6-month period of twice-weekly exercise. Serum IGF-1 levels were assessed at baseline via fasted blood draw. The Johnson-Neyman technique determined whether baseline IGF-1 levels moderated the relationship between changes in aerobic endurance (Δ2MST) and cognition (Δ3MS).

RESULTS

A significant interaction was found; however, Δ2MST was inversely associated with Δ3MS in individuals with above-average serum IGF-1 levels; this relationship was strengthened as IGF-1 increased and was not seen when IGF-1 was below average.

CONCLUSION

The relationship between cognitive and aerobic endurance change varies as a function of IGF-1 in persons with MCI. Additional work is needed to clarify the mechanisms of these findings.

Adapting cognitive remediation to a group home: A brief report

OBJECTIVE

This pilot project was designed to develop procedures for and test the feasibility of implementing Cognitive Enhancement Therapy (CET) in a group home environment, with a goal of maximizing treatment efficacy by augmenting social engagement in group CET sessions with ongoing social interaction.

METHODS

Six participants who met criteria including chronic schizophrenia were recruited in a group home with 30 residents. After two months of CET, pre-and posttest measures, including cognitive tests, were administered and qualitative interviews were conducted periodically. Interaction was observed in the house and staff members were interviewed in a focus group.

RESULTS

Five of the initial six participants completed the intervention-which continued for a total of 45 weeks-engaging in weekly group CET sessions and computer exercises outside of the formal sessions. All participants liked the computer exercises, and all but one participated in and reported enjoying the group exercises. Observations and staff comments indicated increased social interaction and sustained impact for some residents. Some aspects of cognitive functioning improved for some participants during the initial two months.

CONCLUSIONS

CET now needs to be tested more formally to determine if it can be delivered successfully in other group homes with a manualized procedure. The idea should be tested that feedback effects due to the sustained social contact may enhance the effectiveness of CET in group homes and lead to larger, sustained gains in community functioning. Clinicians who provide cognitive interventions should focus attention on the social context in which treatment is delivered and consider providing treatment to patient groups whose daily, ongoing social interaction can enhance its effects.

Depression in Mexican Americans with diagnosed and undiagnosed diabetes

BACKGROUND

Depression and diabetes commonly co-occur; however, the strength of the physiological effects of diabetes as mediating factors towards depression is uncertain.

METHOD

We analyzed extensive clinical, epidemiological and laboratory data from n = 2081 Mexican Americans aged 35-64 years, recruited from the community as part of the Cameron County Hispanic Cohort (CCHC) divided into three groups: Diagnosed (self-reported) diabetes (DD, n = 335), Undiagnosed diabetes (UD, n = 227) and No diabetes (ND, n = 1519). UD participants denied being diagnosed with diabetes, but on testing met the 2010 American Diabetes Association and World Health Organization definitions of diabetes. Depression was measured using the Center for Epidemiological Studies - Depression (CES-D) scale. Weighted data were analyzed using dimensional and categorical outcomes using univariate and multivariate models.

RESULTS

The DD group had significantly higher CES-D scores than both the ND and UD (p ⩽ 0.001) groups, whereas the ND and UD groups did not significantly differ from each other. The DD subjects were more likely to meet the CES-D cut-off score for depression compared to both the ND and UD groups (p = 0.001), respectively. The UD group was also less likely to meet the cut-off score for depression than the ND group (p = 0.003). Our main findings remained significant in models that controlled for socio-demographic and clinical confounders.

CONCLUSIONS

Meeting clinical criteria for diabetes was not sufficient for increased depressive symptoms. Our findings suggest that the 'knowing that one is ill' is associated with depressive symptoms in diabetic subjects.

The role of processing speed in post-stroke cognitive dysfunction

The association between speed of information processing and cognition has been extensively validated in normal aging and other neurocognitive disorders. Our aim was to determine whether such a relationship exists in stroke. Thirty patients and 30 age- and education-matched healthy individuals were administered a comprehensive battery of neuropsychological tests divided into the following six cognitive domains: processing speed (PS), verbal memory, visual memory, visuoperceptual function, language, and cognitive flexibility. The results demonstrate that stroke patients were characterized by cognitive deficits in almost all of these domains, but have the most pronounced deficits in PS. After adjusting for symbol digit modalities test score, all significant group differences in cognitive functioning disappeared. However, group differences remained significant after controlling for the influence of other cognitive factors. These findings suggest that decreased PS appears to underlie post-stroke cognitive dysfunction and may serve as a potential target for intervention.

Adding insult to injury: childhood and adolescent risk factors for psychosis predict lower fractional anisotropy in the superior longitudinal fasciculus in healthy adults

Although epidemiological studies provide strong support for demographic and environmental risk factors in psychotic disorders, few data examine how these risk factors relate to the putative aberrant neurodevelopment associated with illness. The present study examined how the accumulation of risk factors including low IQ, low parental socioeconomic status (SES), history of adolescent cannabis use and childhood trauma, and high levels of subclinical psychotic-like experiences (PLEs) contributed to aberrant neurodevelopmental outcomes in 112 otherwise healthy adults recruited from the community. Participants were studied with diffusion tensor imaging (DTI), and voxel-wise statistical analysis of fractional anisotropy (FA) using tract-based spatial statistics (TBSS) was used to examine the relation between cumulative risk (CR) for psychosis and white matter (WM) integrity across the whole brain. Analyses revealed that higher CR was significantly associated with lower FA in a cluster in the left superior longitudinal fasciculus (SLF). These results suggest that risk factors previously associated with psychotic disorders are associated with WM integrity even in otherwise healthy adults and may provide insight into how previously identified risk factors contribute to the structural brain abnormalities associated with psychotic illness. Prospective longitudinal studies examining the effect of risk factors on the developmental trajectory of brain WM are warranted.

Mild cognitive impairment: a history and the state of current diagnostic criteria

ABSTRACT Background: Mild cognitive impairment (MCI) is a diagnostic classification used to describe patients experiencing cognitive decline but without a corresponding impairment in daily functioning. Over the years, MCI diagnostic criteria have undergone major changes that correspond to advancements in research. Despite these advancements, current diagnostic criteria for MCI contain issues that are reflected in the research literature. Methods: A review of the available MCI literature was conducted with emphasis given to tracing MCI from its conceptual underpinnings to the most current diagnostic criteria. A clinical vignette is utilized to highlight some of the limitations of current MCI diagnostic criteria. Results: Issues are encountered when applying MCI diagnostic criteria due to poor standardization. Estimates of prevalence, incidence, and rates of conversion from MCI to dementia reflect these issues. Conclusions: MCI diagnostic criteria are in need of greater standardization. Recommendations for future research are provided that could potentially bring more uniformity to the diagnostic criteria for MCI and, therefore, more consistency to the research literature.

DTI-measured white matter abnormalities in adolescents with Conduct Disorder

Emerging research suggests that antisocial behavior in youth is linked to abnormal brain white matter microstructure, but the extent of such anatomical connectivity abnormalities remain largely untested because previous Conduct Disorder (CD) studies typically have selectively focused on specific frontotemporal tracts. This study aimed to replicate and extend previous frontotemporal diffusion tensor imaging (DTI) findings to determine whether noncomorbid CD adolescents have white matter microstructural abnormalities in major white matter tracts across the whole brain. Seventeen CD-diagnosed adolescents recruited from the community were compared to a group of 24 non-CD youth which did not differ in average age (12-18) or gender proportion. Tract-based spatial statistics (TBSS) fractional anisotropy (FA), axial diffusivity (AD), and radial diffusivity (RD) measurements were compared between groups using FSL nonparametric two-sample t test, clusterwise whole-brain corrected, p < .05. CD FA and AD deficits were widespread, but unrelated to gender, verbal ability, or CD age of onset. CD adolescents had significantly lower FA and AD values in frontal lobe and temporal lobe regions, including frontal lobe anterior/superior corona radiata, and inferior longitudinal and fronto-occipital fasciculi passing through the temporal lobe. The magnitude of several CD FA deficits was associated with number of CD symptoms. Because AD, but not RD, differed between study groups, abnormalities of axonal microstructure in CD rather than myelination are suggested. This study provides evidence that adolescent antisocial disorder is linked to abnormal white matter microstructure in more than just the uncinate fasciculus as identified in previous DTI studies, or frontotemporal brain structures as suggested by functional neuroimaging studies. Instead, neurobiological risk specific to antisociality in adolescence is linked to microstructural abnormality in numerous long-range white matter connections among many diverse different brain regions.

NIH EXAMINER: conceptualization and development of an executive function battery

Executive functioning is widely targeted when human cognition is assessed, but there is little consensus on how it should be operationalized and measured. Recognizing the difficulties associated with establishing standard operational definitions of executive functioning, the National Institute of Neurological Disorders and Stroke entered into a contract with the University of California-San Francisco to develop psychometrically robust executive measurement tools that would be accepted by the neurology clinical trials and clinical research communities. This effort, entitled Executive Abilities: Measures and Instruments for Neurobehavioral Evaluation and Research (EXAMINER), resulted in a series of tasks targeting working memory, inhibition, set shifting, fluency, insight, planning, social cognition and behavior. We describe battery conceptualization and development, data collection, scale construction based on item response theory, and lay the foundation for studying the battery's utility and validity for specific assessment and research goals.

Multiple resting state network functional connectivity abnormalities in mild traumatic brain injury

Several reports show that traumatic brain injury (TBI) results in abnormalities in the coordinated activation among brain regions. Because most previous studies examined moderate/severe TBI, the extensiveness of functional connectivity abnormalities and their relationship to postconcussive complaints or white matter microstructural damage are unclear in mild TBI. This study characterized widespread injury effects on multiple integrated neural networks typically observed during a task-unconstrained "resting state" in mild TBI patients. Whole brain functional connectivity for twelve separate networks was identified using independent component analysis (ICA) of fMRI data collected from thirty mild TBI patients mostly free of macroscopic intracerebral injury and thirty demographically-matched healthy control participants. Voxelwise group comparisons found abnormal mild TBI functional connectivity in every brain network identified by ICA, including visual processing, motor, limbic, and numerous circuits believed to underlie executive cognition. Abnormalities not only included functional connectivity deficits, but also enhancements possibly reflecting compensatory neural processes. Postconcussive symptom severity was linked to abnormal regional connectivity within nearly every brain network identified, particularly anterior cingulate. A recently developed multivariate technique that identifies links between whole brain profiles of functional and anatomical connectivity identified several novel mild TBI abnormalities, and represents a potentially important new tool in the study of the complex neurobiological sequelae of TBI.

Cortical thickness and folding deficits in conduct-disordered adolescents

BACKGROUND

Studies of pediatric conduct disorder (CD) have described frontal and temporal lobe structural abnormalities that parallel findings in antisocial adults. The purpose of this study was to examine previously unexplored cortical thickness and folding as markers for brain abnormalities in "pure CD"-diagnosed adolescents. On the basis of current frontotemporal theories, we hypothesized that CD youth would have thinner cortex or less cortical folding in temporal and frontal lobes than control subjects.

METHODS

We obtained T1-weighted brain structure images from 24 control and 19 CD participants aged 12 to 18 years, matched by gender and age. We measured group differences in cortical thickness and local gyrification index (regional cortical folding measure) using surface-based morphometry with clusterwise correction for multiple comparisons.

RESULTS

The CD participants, compared with control subjects, showed both reduced cortical thickness and folding. Thinner cortex was located primarily in posterior brain regions, including left superior temporal and parietal lobes, temporoparietal junction and paracentral lobule, right superior temporal and parietal lobes, temporoparietal junction, and precuneus. Folding deficits were located mainly in anterior brain regions and included left insula, ventro- and dorsomedial prefrontal, anterior cingulate and orbitofrontal cortices, temporal lobe, right superior frontal and parietal lobes, and paracentral lobule.

CONCLUSIONS

Our findings generally agree with previous CD volumetric studies but here show the unique contributions of cortical thickness and folding to gray matter reductions in pure CD in different brain regions.

Using monolingual neuropsychological test norms with bilingual Hispanic americans: application of an individual comparison standard

Conventional neuropsychological norms developed for monolinguals likely overestimate normal performance in bilinguals on language but not visual-perceptual format tests. This was studied by comparing neuropsychological false-positive rates using the 50th percentile of conventional norms and individual comparison standards (Picture Vocabulary or Matrix Reasoning scores) as estimates of preexisting neuropsychological skill level against the number expected from the normal distribution for a consecutive sample of 56 neurologically intact, bilingual, Hispanic Americans. Participants were tested in separate sessions in Spanish and English in the counterbalanced order on La Bateria Neuropsicologica and the original English language tests on which this battery was based. For language format measures, repeated-measures multivariate analysis of variance showed that individual estimates of preexisting skill level in English generated the mean number of false positives most approximate to that expected from the normal distribution, whereas the 50th percentile of conventional English language norms did the same for visual-perceptual format measures. When using conventional Spanish or English monolingual norms for language format neuropsychological measures with bilingual Hispanic Americans, individual estimates of preexisting skill level are recommended over the 50th percentile.

Depression and neurocognitive performance in Portuguese patients infected with HIV

This study focused on neurocognitive disorders associated with HIV infection, characterizes the most affected neuropsychological domains and their potential as factors related with depression. 130 HIV-positive individuals with CD4 >200 cells/mm(3), undetectable viral load, treated with HAART and with all kinds of risk behaviors were included. A structured interview composed by seven sections was used and relevant clinical and laboratory data was assessed. For the neuropsychological and depression assessment the HIV Neurobehavioral Research Center (HNRC) Battery and Hamilton Rating Scale for Depression (HAM-D) were chosen. Univariate nonparametric statistics and multivariate regression model were performed. Among 34% of depressed subjects, 20.7% had attempted suicide, 45.4% were under psychiatric medication and only 19% had no diagnostic criteria for HIV Associated Neurocognitive Disorders (HAND). The effect of depression on cognitive function revealed a significant deterioration in five of the eight measures. In the multivariate analysis, five variables significantly determined depression: sex, social class, antidepressant medication, history of suicide attempt and Dexterity and motor speed (neuropsychological test battery). Despite good patient adherence to treatment (HAART and antidepressive) and good immune status, the prevalence of HAND and depression are high and suggest a significant relation between severity of depression and cognitive functioning.

Relationship between global cognitive decline and depressive symptoms in multiple sclerosis

Cognitive impairment and depressed mood are common symptoms in multiple sclerosis (MS), which significantly impact patients' role functioning and quality of life. Cross-sectional studies indicate a modest association between cognitive impairment and depressive symptoms in MS. Longitudinal studies show inconsistent results but provide some data indicating a relationship between increasing global cognitive decline and increasing depressive symptoms over time. Establishing whether such a relationship exists represents an important first step in understanding the temporal nature of that relationship along with any treatment implications. The current study investigated this relationship by using the adjusted difference between a demographic estimate of premorbid intellectual functioning (Barona) and a performance measure of current intellectual functioning (Shipley Institute of Living) to capture long-term global cognitive decline in MS patients. Degree of global cognitive decline was then related to a self-report measure of mood, evaluative, and vegetative depression symptoms (Chicago Multiscale Depression Inventory). Global cognitive decline accounted for 5% of the variance in mood-evaluative symptoms but none of the variance in vegetative symptoms. When groups experiencing moderate, mild, and no global cognitive decline were compared on depression symptom subscales, MS patients experiencing moderate cognitive decline reported significantly higher mood and evaluative, but not vegetative, depressive symptoms than MS patients with stable cognitive functioning.

Impact of traumatic and violent victimization experiences in individuals with schizophrenia and schizoaffective disorder

Individuals with schizophrenia or schizoaffective disorder (SZ) experience more violent victimization and noninterpersonal traumatic experiences than the general population. Earlier studies, however, have generally excluded one or grouped together victimization and trauma experiences into single outcome variables, which may obscure their contributory role to SZ symptoms. This issue is important because there is some evidence that intentionally induced violence produces higher rates of psychopathology than nonintentional traumatic experiences. We examined the independent contribution of both types of victimization experiences on SZ patients' symptomatology. We were also interested in determining whether SZ patients' pattern of acute symptom presentation could discriminate between SZ patients with and without posttraumatic stress disorder (PTSD) comorbidity. SZ inpatients (n = 70) were assessed for the presence of comorbid PTSD diagnosis, violent victimization, and noninterpersonal traumatic experiences. Patients were also rated on SZ symptom severity and general psychopathology measures. Past violent victimization experiences predicted severity of dysphoria and anxiety in SZ. Past traumatic experiences, however, predicted severity of psychosis. Victimization predicted severity of patients' autistic/cognitive symptoms. SZ patients with comorbid PTSD presented with significantly more anxiety and dysphoria symptoms and SZ illness chronicity than their non-PTSD counterparts. Discriminant function analysis revealed that the severity of positive, dysphoric, autistic/cognitive, and anxiety symptoms differentiated comorbid PTSD patients from their non-PTSD counterparts, with an overall 72.9% classification rate. Past traumatic and victimization experiences are significantly associated with SZ patients' symptom severity and illness course in partially overlapping domains. Use of common assessment strategies may be employed to increase detection of PTSD in SZ patients presenting for acute treatment.

Cognitive and psychological factors associated with early posttreatment functional outcomes in breast cancer survivors

Breast cancer survivors experience cognitive difficulties following chemotherapy, yet the effects of these deficits on functional outcomes have not been systematically evaluated. This study assessed the relationships between postchemotherapy cognitive difficulties and functional outcomes. Forty-six women with breast cancer were seen at 1-month postchemotherapy; data were collected on cognitive functioning, psychological variables, and physical symptoms. Wilcoxon signed-rank analyses revealed cognitive deficits in executive functioning and verbal fluency. Subsequent regression analyses demonstrated that poorer executive functioning was associated with decreased productivity, community involvement, and social role functioning. Poorer quality of life was predicted by depression and reluctance to seek social support, but not cognitive functioning. These findings indicate that executive functioning deficits are associated with important functional outcomes among breast cancer survivors 1-month postchemotherapy. Thus, treatment efforts should focus on addressing cognitive, as well as psychological and physical, issues among cancer survivors.

Computerized cognitive assessment of mild cognitive impairment in urban African Americans

Few objective cognitive assessment tools have been validated for mild cognitive impairment (MCI) in African Americans despite higher prevalence of disease. This preliminary study evaluated discriminant validity of a computerized cognitive assessment battery for MCI in an urban African American cohort. Twenty-seven participants with MCI and 22 cognitively healthy individuals completed a multidomain battery (Mindstreams, NeuroTrax Corp, New Jersey). Mild cognitive impairment participants performed more poorly than cognitively healthy participants in all domains, with significant differences in memory (P = .003; d = 0.96), executive function (P = .046; d = 0.64), and overall battery performance (P = .041; d = 0.63). Adjustment for intelligence quotient (IQ) yielded significant differences in memory (P < .001; d = 1.34), executive function (P = .007; d = 0.86), attention (P = .014; d = .80), and overall performance (P = .001; d = 1.09). Such a validated battery may help to address an important clinical need in this population.

Neuropsychological functioning of U.S. Gulf War veterans 10 years after the war

Many U.S. Gulf War-era veterans complained of poor cognition following the war. This study assessed neuropsychological functioning in veterans 10 years after the war through objective tests. 2189 Gulf War-era veterans (1061 deployed, 1128 non-deployed) were examined at 1 of 16 U.S. Veterans Affairs medical centers. Outcomes included neuropsychological domains derived from factor analysis and individual test scores. Deployed veterans performed significantly worse than non-deployed veterans on 2 of 8 factors (motor speed & sustained attention, analysis not corrected for multiple comparisons) and on 4 of 27 individual test variables (Trails A & B, California Verbal Learning Test-List B, and Continuous Performance Test sensitivity, with only Trails B surviving Bonferroni correction). Within deployed veterans, Khamisiyah exposure was negatively correlated with motor speed after controlling for emotional distress. Depressive symptoms and self-reported exposure to toxicants were independently and significantly associated with worse sustained attention. Other factors were also associated with self-reported exposures. The findings were not a result of differential effort across groups. Gulf War deployment is associated with subtle declines of motor speed and sustained attention, despite overall intact neuropsychological functioning. Evidence suggests that toxicant exposures influence both these functions, and depressive symptoms also influence attention.

Adjustment of cognitive scores with a co-normed estimate of premorbid intelligence: implementation using mindstreams computerized testing

Neuropsychological assessment is critically dependent upon comparison to a standard normative database. While generally appropriate for individuals of near-average intelligence, high-intelligence individuals may be erroneously scored as unimpaired and low-intelligence individuals as impaired on cognitive measures. The current paper describes an approach for minimizing such misclassifications that is standardized and practical for clinical use. A computerized test of nonverbal reasoning co-normed with cognitive measures is used for automatic adjustment of normalized cognitive scores. This premorbid estimate showed good construct validity, and adjustment raised cognitive scores for low-intelligence individuals, and lowered cognitive scores for high-intelligence individuals similarly across demographic (age, education, computer experience) and clinical (cognitively healthy, mild cognitive impairment, dementia) subgroups. Adjustment was typically up to three normalized units for scores on the premorbid estimate of +/-1 SD and 6 normalized units for scores of +/-2 SD. The present approach shows promise as a practical solution for assessment of high- and low-intelligence individuals.

The neuregulin 1 promoter polymorphism rs6994992 is not associated with chronic schizophrenia or neurocognition

The neuregulin 1 (NRG1) promoter single nucleotide polymorphism (SNP) rs6994992 has shown association with decreased activation of frontal and temporal lobe regions, increased risk of psychosis, and decreased premorbid IQ. This SNP is part of a putative schizophrenia risk-associated haplotype and was associated with increased expression of the type IV transcript in postmortem tissue. We tested for association between rs6994992 and chronic schizophrenia by genotyping 738 cases from the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) and 733 matched controls. We further tested for associations with age at onset and baseline neurocognition in cases with schizophrenia reasoning that these phenotypes might yield results similar to those seen for premorbid IQ. Affection status was weakly associated with rs6994992 genotypes and trended towards association under a recessive model. This association did not survive correction for multiple comparisons and was in the opposite direction than has been reported. There was no association between rs6994992 and age at onset, an estimate of premorbid IQ, or neurocognition at study baseline. We were unable to replicate previous associations of rs6994992 with schizophrenia and, moreover, did not find significant associations with age of onset, an estimate of pre-morbid IQ, or neurocognition.

Estimating premorbid intelligence in schizophrenia patients: demographically based approach

OBJECTIVE

The aim of the present study was to provide a useful and quick estimate of premorbid intelligence that can be used in the population of schizophrenia patients.

METHOD

Regression analysis (stepwise procedure) was used to identify which of five demographic variables significantly predicted National Adult Reading Test (NART) scores in schizophrenia patients. The new regression equation was subsequently assessed in an independent patient sample. The results were compared with scores obtained for an equation developed in healthy populations.

RESULTS

Age, occupation, and education contributed significantly to the equation, which accurately predicted NART scores in the patient sample. The equation developed in healthy people, however, consistently underestimated NART scores.

CONCLUSIONS

Equations developed in healthy people are not accurate predictors of NART scores. By contrast, the new equation acknowledges the educational and occupational characteristics typical of individuals with schizophrenia. The equation should be used cautiously, but can be used as a rapid estimate when it is not possible to conduct a cognitive assessment using more traditional approaches.

Effects of acute caffeine withdrawal on Short Category Test performance in sleep-deprived individuals

Caffeine is a popular stimulant often used to counter the effects of sleep loss and fatigue. Withdrawal from caffeine may produce mild declines in simple cognitive capacities such as attention and concentration, but it is unclear whether more complex cognitive functions, such as abstract reasoning or concept formation, may be similarly affected. To assess the effect of acute caffeine withdrawal on executive functioning during sleep deprivation, 26 healthy volunteers were administered in double-blind form either repeated doses of caffeine or placebo over two nights of continuous wakefulness. The 108-item Short Category Test was administered after 56 hr. of total sleep deprivation (9 hr. post-caffeine administration). The caffeine group scored significantly more poorly, making approximately 57% more errors on the test than the placebo group. These findings suggest that acute caffeine withdrawal during prolonged sleep deprivation has an adverse effect on abstract reasoning and concept formation.

Neuropsychological and symptom predictors of aggression on the psychiatric inpatient service

Neuropsychological assessment of executive dysfunction may identify psychiatric patients who may be at high risk for aggressive behavior because impairment of the prefrontal cortex has been indicated as a possible anatomical correlate of aggression. No consensus, however, has been reached on the extent that executive dysfunction contributes to the formation of psychopathology and to aggressive behavior in psychiatric inpatients. We hypothesized a mediating model wherein patients' executive-functioning deficits contribute to the formation of psychopathological symptoms, which then underlies aggressive behavior. To test this model, we examined the relationship between executive functioning, psychiatric symptomatology, and aggressive behavior in 85 psychiatric inpatients presenting over an acute hospital admission using structure equation modeling techniques. The results revealed that psychiatric inpatients' executive function impairment significantly predicted the formation of psychiatric symptomatology, which in turn significantly contributed to the manifestation of aggressive behavior. Executive dysfunction also directly predicted inpatient aggressive behavior. Combining the indirect and direct effects, 59% of our inpatient aggression measure factor variance was accounted for by our measures of executive dysfunction and clinical symptom severity. These findings suggest that neurocognitive deficits underlie both psychiatric symptom formation and aggression. Patients with executive dysfunction may not possess the behavioral inhibition skills needed to cope with the presence of symptoms and other stressful events that accompany acute psychosis and hospitalization that may result, consequently, in increased manifestations of aggressive behavior.

Predictors of medication competence in schizophrenia patients

Competence in self-administration of a drug regimen is related to both treatment adherence and functional outcome. Previous research with middle-aged and older schizophrenia patients suggests a central role for cognitive performance in predicting this competence. We examined the relative and joint contributions of demographic, clinical and cognitive predictors of medication management ability in an age-representative group of patients. The study participants comprised 147 patients with schizophrenia or schizoaffective disorder ranging from 21 to 65 years of age. Measures included demographic variables, current symptoms, subjective treatment response and a battery of cognitive tests. Competence in medication management was indexed with the Medication Management Ability Assessment (MMAA). Multiple regression analyses revealed that cognitive variables accounted for a significant proportion of the variance in MMAA scores over and above the contribution of all other variables. Measures of word recognition and pronunciation, auditory working memory and verbal learning yielded unique contributions to prediction. Positive and negative symptoms and subject treatment evaluations did not independently predict medication competency. This study documents a considerable range in MMAA scores across a demographically broad schizophrenia sample and supports the unique contribution of specific cognitive factors in predicting medication competence.

Motor asymmetry and substantia nigra volume are related to spatial delayed response performance in Parkinson disease

Studies suggest motor deficit asymmetry may help predict the pattern of cognitive impairment in individuals with Parkinson disease (PD). We tested this hypothesis using a highly validated and sensitive spatial memory task, spatial delayed response (SDR), and clinical and neuroimaging measures of PD asymmetry. We predicted SDR performance would be more impaired by PD-related changes in the right side of the brain than in the left. PD (n=35) and control (n=28) participants performed the SDR task. PD participants either had worse motor deficits on the right (RPD) or left (LPD) side of the body. Some participants also had magnetic resonance imaging for measurement of their substantia nigra (SN) volumes. The LPD group performed worse on the SDR task than the RPD and control groups. Right SN volume accounted for a unique and significant portion of the variance in SDR error, with smaller volume predicting poorer performance. In conclusion, left motor dysfunction and smaller right SN volume are associated with poorer spatial memory.

Predictors of cognitive impairment in type 1 diabetes

A decline in cognitive function has been reported in type 1 diabetes, but its relation to different disease factors such as hypoglycemic events and peripheral neuropathy is controversial. The objective of the present study was to identify factors that are important for cognitive impairment in type 1 diabetes. A cross-sectional study was performed in adult patients (N=150) with type 1 diabetes (duration 26.6+/-11.4 years). Function in different cognitive domains was evaluated by the same trained examiner, in order to eliminate inter-rater variability. Peripheral nerve function was tested quantitatively. Predictors of cognitive impairment were identified using multiple regression analysis. The major finding was that long diabetes duration and young age of diabetes onset were the strongest predictors of low scores in psychomotor speed, memory, processing speed, attention, working memory, verbal ability, general intelligence, executive functions and a low global score. The number of previous hypoglycemic events had no defined effect upon cognitive functioning. Other significant predictors were low compound muscle action potential (CMAP) (for visual perception-organization), old age (for visual-spatial ability), short stature, high BMI and hypertension. Presence of retinopathy and long-term metabolic control correlated with nerve conduction defects, but not with cognitive impairment. Although a history of hypoglycemic events was not a predictor of cognitive impairment, we cannot exclude the possibility that the influence of young age of diabetes onset depends on the effect of hypoglycemic events early in life. The clinical relationships of cognitive impairment differ from those of peripheral neuropathy, indicating a different pathogenesis. The influence of diabetes duration, BMI, height, age and CMAP may suggest that loss of the neuroprotective effects of insulin or insulin-like growth factors plays a role.

Anti-N-methyl-D-aspartate receptor antibodies, cognitive dysfunction, and depression in systemic lupus erythematosus

OBJECTIVE

To assess the association of cognitive dysfunction and depression with serum antibodies to N-methyl-D-aspartate (NMDA) receptor (anti-NR2) and analyze clinical and neuroimaging correlates in patients with systemic lupus erythematosus (SLE).

METHODS

Sixty patients underwent neurocognitive assessment, evaluation for depression with the Beck Depression Inventory II (BDI-II) and psychiatric interview (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition [DSM-IV] criteria), brain magnetic resonance imaging, and proton magnetic resonance spectroscopy imaging (1H-MRSI). Cognition was assessed in 5 domains: memory, attention/executive, visuospatial, motor, and psychomotor, and adjusted to each individual's best level of prior cognitive functioning estimated from the reading subtest of the Wide Range Achievement Test-3 (WRAT-3). Serum anti-NR2 antibodies were measured by enzyme-linked immunosorbent assay using a pentapeptide from the human NMDA receptor.

RESULTS

Cognitive dysfunction was found in 28 of 60 patients (mild in 8, moderate in 20) before adjustment for WRAT-3 and in 35 of 60 patients (mild in 15, moderate in 11, and severe in 9) after adjustment for WRAT-3. The changes were most pronounced in the memory and visuospatial domains. There was no significant association between anti-NR2 antibody levels and cognition. On 1H-MRSI, patients with moderate or severe cognitive dysfunction had significantly higher choline:creatine ratios in the dorsolateral prefrontal cortex and the white matter, compared with patients with mild or absent cognitive dysfunction. Anti-NR2 antibodies were significantly correlated with BDI scores; patients with BDI-II scores of > or =14 had higher serum levels of anti-NR2 antibodies (P = 0.005, 95% confidence interval 0.83, 4.31), and there was a trend toward higher anti-NR2 antibody levels among patients who fulfilled the DSM-IV criteria for major depression.

CONCLUSION

Serum anti-NR2 antibodies are associated with depressive mood but not with cognitive dysfunction in SLE at a given time point. Larger longitudinal studies are needed to address the possible association between anti-NR2 antibodies and depression in SLE.

Neurocognitive and social cognitive predictors of interpersonal skill in schizophrenia

Social dysfunction is among the major criteria for receiving a diagnosis of schizophrenia, and research indicates that the impairments in social functioning experienced by individuals with schizophrenia are strongly related to deficits in interpersonal skills. In turn, these deficits in interpersonal skills have been linked to impairments in general cognitive abilities and impairments in social cognition. This study explored the relationship between neurocognition, social cognition, and interpersonal skills in 49 outpatients with schizophrenia and 44 non-clinical control participants. Results indicate that individuals with schizophrenia demonstrated impaired performance across several domains of neurocognitive and social cognitive functioning as well as interpersonal skills. In addition, among the participants with schizophrenia, social cognition significantly contributed unique variance to interpersonal skill beyond that of neurocognition. This pattern was not observed in the non-clinical control sample. These findings have implications for the treatment of the disorder and represent an important step in understanding the role of social cognition in schizophrenia.

Use of computerized assessment to predict neuropsychological functioning and emotional distress in patients with systemic lupus erythematosus

OBJECTIVE

Cognitive dysfunction and neuropsychiatric disturbance are common in systemic lupus erythematosus (SLE). This study addressed the ability of the Automated Neuropsychological Assessment Metrics (ANAM), a computerized cognitive testing battery consisting of cognitive subtests, a sleepiness rating scale, and a mood scale, to predict neuropsychological status in patients with SLE.

METHODS

Sixty individuals with SLE and no overt neuropsychiatric symptoms were administered ANAM to determine its validity as a screening measure of cognitive dysfunction and emotional distress in SLE.

RESULTS

Performance on ANAM was compared with results of a consecutively administered, 2-hour battery of traditional neuropsychological tests and the Beck Depression Inventory II (BDI-II). Individual ANAM cognitive test scores were significantly correlated with most neuropsychological tests, particularly those measuring psychomotor processing speed and executive functioning. Using logistic regression, ANAM cognitive subtests successfully predicted individuals with SLE who had probable versus no impairment after controlling for premorbid levels of cognitive ability. Sensitivity of group classification was 76.2% and specificity was 82.8%, with 80% correct classification overall. ANAM's ability to predict neuropsychological functioning remained even after controlling for subjective reports of depressed mood and current sleepiness. Further, the ANAM mood scale was significantly correlated with the BDI-II (r = 0.67, P < 0.001), indicating its potential future use as a screening tool for emotional distress.

CONCLUSION

ANAM shows promise as a time- and cost-efficient tool for screening and monitoring cognitive and emotional functioning in SLE, and can indicate when a more thorough neuropsychological investigation is warranted.

Reading ability mediates the relationship between education and executive function tasks

Neuropsychological test results are affected by multiple factors, but usually age and education are the only variables by which norms are stratified. Some authors have questioned whether these variables alone are sufficient (e.g., Marcopulos et al., 1997; Manly et al., 2002), since such norms have lead to problems, such as poor specificity for African Americans on dementia screening devices (Fillenbaum et al., 1990). Recent research has shown that reading ability, a measure of educational quality, attenuated racial differences in test performance (Manly et al., 2002). We specifically examined whether reading ability would account for a greater amount of variance than education in executive function tests in a population traditionally subject to poor educational quality. Results determined that reading ability accounted for a significantly greater amount of variance than years of education for Letter-Number Sequencing, Similarities, COWA, Trail Making Test, and Coloured Progressive Matrices. Reading ability was found to significantly mediate the relationship between each of these tests and education. Animal naming appears to be least affected by educational quality or quantity. These findings hold implications for the interpretation of neuropsychological test results, especially in those exposed to substandard educational quality, and for the way that test norms are constructed.

Comparison of measured and estimated cognitive ability in older adolescents with and without ADHD

Premorbid intellectual function estimation is a crucial part of patient evaluation following a traumatic brain injury (TBI), especially in individuals with ADHD who are at higher risk for TBI compared to their non-ADHD peers. This study investigates the value of using regression-based estimates of intelligence for concurrently predicting measured intelligence in a sample of older adolescents with and without a childhood history of ADHD. Correlations between measured and estimated intelligence are highly significant in the full sample and in the individual groups. Adding reading performance to the regression equation increases the accounted-for variance in both groups. Results indicate that regression equations based on demographic characteristics constitute a valid method for estimating premorbid functioning in adolescents with ADHD and that they can play an essential role in the assessment of individuals with ADHD who sustain TBI, especially when measures of word reading are used to augment demographic estimates.

Evaluation of two methods for estimating Premorbid Intelligence on the WAIS-III in a clinical sample

Two methods of predicting premorbid WAIS-III Full Scale IQ, namely a demographic measure (DP IQ) and the Oklahoma Premorbid Intelligence Estimate-3 (OPIE-3), were assessed in three traumatic brain injury (TBI) groups of varying injury severity and normal controls. On the DP IQ, average scores were in keeping with the general population mean across all groups but range was severely restricted. OPIE-3 IQ scores were not subject to severe range restriction and were comparable with the general population mean in the control and least severely brain injured group. They were significantly lower relative to controls in the severe and extremely severe TBI groups, with differences averaging around 7 and 10 points, respectively. OPIE-3 (Best) proved particularly robust in more severely injured subjects. Effect sizes for the combined TBI sample relative to controls were greatest for OPIE-3 measures that included two non-verbal subtests and were least for that involving vocabulary only. Implications of the findings for clinical practice and further research are discussed.