Relevanz der Neuropsychologie für die Rehabilitation von Epilepsiepatienten

A comprehensive interdisciplinary approach including medical treatment, neuropsychological and psychiatric assessment, occupational therapy, social work counselling and physical exercise is a prerequisite for effective rehabilitation of patients with epilepsy. Concerning the high rates of unemployment and early disability in patients with epilepsy, work (re)integration is the main goal of rehabilitation. A literature review on the relevance of neuropsychological findings for vocational rehabilitation suggests that intelligence or other measures of general cognitive abilities seem to be more closely related to employment status than specific deficits, such as verbal memory. The main task of neuropsychology in rehabilitation is the diagnosis and therapy of cognitive impairments. A professionally experienced interpretation of test results is crucial, especially with respect to functional relevance for work performance and further rehabilitation planning. A systematic overview of the functional implications of specific cognitive impairments and suggested interventions is given. Close collaboration of the different professions involved in rehabilitation interventions is extremely helpful for a correct interpretation of test results and other findings of neuropsychological assessment.     

The relationship between neuropsychological measures and the Timed Instrumental Activities of Daily Living task in multiple sclerosis

Multiple sclerosis (MS) can result in cognitive deficits and a loss of functional independence. To date, little research has linked the observed cognitive and behavioral deficits in MS, especially those in the processing speed domain, to performance on tasks of everyday functioning. The present study examined the relationship between neuropsychological test performance and performance on the Timed Instrumental Activities of Daily Living task (TIADL) in individuals with MS, and in healthy controls (HCs). The TIADL is a functional measure, which assesses both accuracy and speed in one's performance of everyday activities. The MS group performed significantly worse on the TIADL relative to the HC group. Additionally, TIADL scores of individuals with MS were significantly correlated with neuropsychological measures of processing speed. TIADL scores were not, however, correlated with neuropsychological measures of verbal episodic memory or working memory. These results indicate that the impairments in processing speed may contribute to impairments in activities of everyday living in persons with MS.     

The relationship of neuropsychological abilities to specific domains of functional capacity in older schizophrenia patients.

BACKGROUND: This study sought to determine the relative importance of cognitive measures in predicting various domains of everyday functional capacity in older outpatients with schizophrenia. METHODS: Ninety-three psychiatry outpatients with diagnoses of schizophrenia and schizoaffective disorders underwent a comprehensive neuropsychiatric evaluation, including neuropsychological testing and clinical ratings of psychopathology. Functional capacity was assessed with the Direct Assessment of Functional Status, a performance measure of basic and instrumental activities of daily living (ADLs/IADLs). RESULTS: Neuropsychological performance significantly predicted most ADLs/IADLs measured, except simple eating behaviors, time orientation, and grooming. Lower educational level and negative symptoms also were associated with worse functional capacity, whereas positive symptoms and depressed mood were not. Measures of cognitive functioning accounted for more variance in functional capacity than did psychiatric ratings of symptoms, and multiple regression analyses demonstrated that neuropsychological performance was predictive of functional capacity, over and above clinical symptoms. No specific cognitive domains were differentially predictive of specific domains of functional capacity. CONCLUSIONS: Neurocognitive abilities were more predictive of functional capacity than level of clinical symptoms; however, these abilities were not specific predictors of functioning. This is consistent with findings of relatively generalized, intercorrelated cognitive impairment in schizophrenia and multiply determined domains of everyday functioning.     

Clinical, functional, and intertask correlations of measures developed by the Cognitive Neuroscience Test Reliability and Clinical Applications for Schizophrenia Consortium

The goal of the Cognitive Neuroscience Test Reliability and Clinical Applications for Schizophrenia (CNTRACS) Consortium was to develop measures of discrete cognitive processes, allowing for the interpretation of specific deficits that could be linked to specific neural systems. Here we report on the intertask, clinical, and functional correlates of the 4 tasks that were investigated in large groups of patients with schizophrenia (>100) and healthy controls (>73) at 5 sites across the United States. In both healthy and patient groups, the key dependent measures from the CNTRACS tasks were minimally intercorrelated, suggesting that they are measuring discrete abilities. Correlations were examined between CNTRACS tasks and measures of functional capacity, premorbid IQ, symptom severity, and level of community functioning. Performance on tasks measuring relational memory encoding, goal maintenance, and visual gain control were correlated with premorbid IQ and the former 2 tasks with the functional capacity. Goal maintenance task performance was negatively correlated with negative symptom severity and informant reports of community function. These correlations reflect the relationship of specific abilities with functional outcome. They are somewhat lower than functional outcome correlations observed with conventional neuropsychological tests that confound multiple cognitive and motivational deficits. The measures of visual integration and gain control were not significantly correlated with clinical symptoms or function. These results suggest that the CNTRACS tasks measure discrete cognitive abilities, some of which relate to aspects of functional capacity/outcome in schizophrenia.     

Mild cognitive impairment and everyday functioning in older adults

The relations between mild cognitive impairment without dementia (MCI/CIND) and everyday functional abilities were examined using data from the Canadian Study of Health and Aging (CSHA). Individuals were identified with MCI/CIND if both caregiver report and clinician judgment agreed on the presence of cognitive impairment in the absence of dementia. Cross-sectional and longitudinal comparisons indicated that individuals with MCI/CIND demonstrated a broad range of impairment in instrumental activities of daily living (IADL) compared to individuals with no cognitive impairment (NCI). In cross-sectional analyses, neuropsychological measures of memory and psychomotor speed were significantly related to impairment in eight areas of functioning. In addition, poorer memory performance was significantly predictive of future impairment in money management.     

WAIS-IV visual puzzles in a mixed clinical sample

Little is known about which cognitive functions underlie the new Visual Puzzles subtest of the Wechsler Adult Intelligence Scale - Fourth Edition (WAIS-IV). The purpose of this study was to investigate relationships between Visual Puzzles and common neuropsychological measures in a mixed clinical sample. A total of 44 veterans (75% men) were administered the WAIS-IV as part of a neuropsychological evaluation. Average age was 47.4 years (SD = 11.8), and average education was 13.8 years (SD = 2.3). Correlations were conducted to examine relationships between Visual Puzzles, demographic variables, and neuropsychological measures. Hierarchical regression analysis was used to determine which measures contributed the most variance to Visual Puzzles. Visual Puzzles correlated significantly with measures of visuospatial reasoning, verbal learning and recall, mental flexibility, processing speed, and naming, which accounted for 50% of the variance in Visual Puzzles performance. The results indicate that Visual Puzzles is not a pure measure of visuoperceptual reasoning, at least in a mixed clinical sample, because memory, mental flexibility, processing speed, and language abilities also contribute to successful performance of the task. Thus it may be important to consider other aspects of cognitive functioning when interpreting Visual Puzzles performance.     

Mild cognitive impairment and everyday functioning in older adults

The relations between mild cognitive impairment without dementia (MCI/CIND) and everyday functional abilities were examined using data from the Canadian Study of Health and Aging (CSHA). Individuals were identified with MCI/CIND if both caregiver report and clinician judgment agreed on the presence of cognitive impairment in the absence of dementia. Cross-sectional and longitudinal comparisons indicated that individuals with MCI/CIND demonstrated a broad range of impairment in instrumental activites of daily living (IADL) compared to individuals with no cognitive impairment (NCI). In cross-sectional analyses, neuropsychological measures of memory and psychomotor speed were significantly related to impairment in eight areas of functioning. In addition, poorer memory performance was significantly predictive of future impairment in money management.     

Neuropsychological predictors of BOLD response during a spatial working memory task in adolescents: what can performance tell us about fMRI response patterns?

The relationship between standardized neuropsychological test performance and functional magnetic resonance imaging (fMRI) response during cognitive tasks is largely unknown. This exploratory investigation examined the relationship between neuropsychological test performance and fMRI response to a spatial working memory (SWM) task among 49 typically developing adolescents. Participants were administered a variety of neuropsychological tests in the domains of working memory, visuospatial skills, executive functioning, attention, learning and memory, visuomotor skills and processing speed, and language functioning. Neuropsychological domain scores were used to predict fMRI response during a SWM task. Results suggest that in many brain regions, neuropsychological performance negatively predicts fMRI response, suggesting that those teens with better neuropsychological abilities required fewer neural resources to adequately perform the task. This study provides further understanding of how neuropsychological abilities relate to neural activity during fMRI tasks, and provides an important link between neuropsychological and fMRI research.     

Cognitive outcome of survivors of space-occupying hemispheric infarction

In patients with space-occupying hemispheric infarction, surgical decompression within 48 h after stroke onset increases the chance of a good functional outcome, but also the chance of survival with severe disability. Until now, cognitive outcome in these patients has not been reported in a consecutive series. Participants of the hemicraniectomy after middle cerebral artery infarction with life-threatening edema trial (HAMLET; ISRCTN94237756) underwent detailed neuropsychological examination at a median of 14.5 months after stroke onset. ‘Global cognitive impairment’ was defined as a score on the Cambridge cognitive examination (CAMCOG) ≤ 83. Impairment on an individual neuropsychological task was defined as a score below the 2.5th percentile or more than two standard deviations below standard norms. The association between cognitive and functional outcome was analysed with linear regression. Twenty patients were tested. Fifteen (75 %) had global cognitive impairment or such poor performance that assessment of global cognitive performance by the CAMCOG was not feasible. Five had only focal cognitive deficits. Still, detailed neuropsychological examination was feasible in 18 patients. Patients with aphasia performed worse than those without on both verbal and non-verbal tasks. Poorer cognitive performance was associated with worse functional outcome as assessed with the modified Rankin scale (β ?0.4, 95 % CI ?0.6 to ?0.1). No differences were observed between operated and non-operated patients. The majority of survivors of space-occupying hemispheric infarction suffered from long-term global cognitive impairment. Isolated focal neuropsychological deficits were found in only a quarter. Impaired cognitive outcome was associated with worse functional outcome.     

The relationship of prenatal and perinatal complications to cognitive functioning at age 7 in the New England Cohorts of the National Collaborative Perinatal Project

Previous literature shows that children who later develop schizophrenia have elevated rates of prenatal and perinatal complications (PPCs) and neuropsychological deficits in childhood. However, little is known about the relationship of these risk factors to each other. We evaluated the relationship between PPCs and neuropsychological functioning at age 7 in a large epidemiological study of pregnancy, birth, and development: the National Collaborative Perinatal Project (NCPP). Thirteen standardized measures of cognitive abilities were acquired on 11,889 children at approximately age 7. Principal components analysis was used to create three neuropsychological measures: academic achievement skills, verbal-conceptual abilities, and perceptual-motor abilities. We measured the relationship between these factors and three measures of PPCs: low birth weight (LBW), probable hypoxicischemic complications, and chronic hypoxia. All three measures of PPCs were significantly associated with lower neuropsychological performance, after controlling for various confounders. LBW had the strongest association with neuropsychological performance, followed by an index of presumed hypoxic insults. The effect sizes between PPCs and cognitive factors at age 7 were consistently largest with perceptual-motor abilities, followed by academic achievement skills and verbal-conceptual abilities. Future studies will evaluate the effects of specific PPCs and genetic risk factors for psychosis on cognitive functioning in childhood.     

The impact of HIV-associated neuropsychological impairment on everyday functioning.

HIV-1 infection can be associated with neuropsychological (NP) deficits ranging from subtle to severe. The purpose of this study was to evaluate the functional, or "real-world" impact of HIV-associated NP impairment in a group of 267 HIV-infected participants. All participants received comprehensive NP, neuromedical, and standardized functional evaluations that included laboratory measures of shopping, cooking, financial management, medication management and vocational abilities. Compared to NP-normal participants, those with NP impairment performed significantly worse on all laboratory measures of everyday functioning. Multivariate analyses revealed that the NP ability domains of Abstraction/Executive Function, Learning, Attention/Working Memory and Verbal abilities most strongly and consistently predicted failures on the functional battery. Both NP impairment and impairment on the functional battery were significantly associated with subjective experiences of cognitive difficulties, as well as unemployment and increased dependence in activities of daily living; multivariate prediction models that also considered depressed mood and biological measures of disease progression revealed that impairment on the functional battery and depression were the only unique predictors of all three indicators of "real-world" functioning. The current results add to growing evidence concerning the clinical significance of HIV-associated NP impairment. Objective, laboratory based functional measures, such as those used here, may compliment NP testing in future studies directed at understanding the impact on life quality of central nervous system disorders and their treatments. Finally, there is a need for additional research investigating the apparently independent effect of depression on level of everyday functioning in HIV infected persons.     

Virtual reality measures in neuropsychological assessment: a meta-analytic review

Objective: Virtual reality-based assessment is a new paradigm for neuropsychological evaluation, that might provide an ecological assessment, compared to paper-and-pencil or computerized neuropsychological assessment. Previous research has focused on the use of virtual reality in neuropsychological assessment, but no meta-analysis focused on the sensitivity of virtual reality-based measures of cognitive processes in measuring cognitive processes in various populations. Method: We found eighteen studies that compared the cognitive performance between clinical and healthy controls on virtual reality measures. Results: Based on a random effects model, the results indicated a large effect size in favor of healthy controls (g = .95). For executive functions, memory and visuospatial analysis, subgroup analysis revealed moderate to large effect sizes, with superior performance in the case of healthy controls. Participants’ mean age, type of clinical condition, type of exploration within virtual reality environments, and the presence of distractors were significant moderators. Conclusions: Our findings support the sensitivity of virtual reality-based measures in detecting cognitive impairment. They highlight the possibility of using virtual reality measures for neuropsychological assessment in research applications, as well as in clinical practice.     

Characterization of cognitive and motor performance during dual-tasking in healthy older adults and patients with Parkinson’s disease

The primary purpose of this study was to investigate the effect of dual-tasking on cognitive performance and gait parameters in patients with idiopathic Parkinson’s disease (PD) without dementia. The impact of cognitive task complexity on cognition and walking was also examined. Eighteen patients with PD (ages 53–88, 10 women; Hoehn and Yahr stage I-II) and 18 older adults (ages 61–84; 10 women) completed two neuropsychological measures of executive function/attention (the Stroop Test and Wisconsin Card Sorting Test). Cognitive performance and gait parameters related to functional mobility of stride were measured under single (cognitive task only) and dual-task (cognitive task during walking) conditions with different levels of difficulty and different types of stimuli. In addition, dual-task cognitive costs were calculated. Although cognitive performance showed no significant difference between controls and PD patients during single or dual-tasking conditions, only the patients had a decrease in cognitive performance during walking. Gait parameters of patients differed significantly from controls at single and dual-task conditions, indicating that patients gave priority to gait while cognitive performance suffered. Dual-task cognitive costs of patients increased with task complexity, reaching significantly higher values then controls in the arithmetic task, which was correlated with scores on executive function/attention (Stroop Color-Word Page). Baseline motor functioning and task executive/attentional load affect the performance of cognitive tasks of PD patients while walking. These findings provide insight into the functional strategies used by PD patients in the initial phases of the disease to manage dual-task interference.     

Altered functional adaptation to attention and working memory tasks with increasing complexity in relapsing-remitting multiple sclerosis patients

As attention, processing speed, and working memory seem to be fundamental for a broad range of cognitive performance, the present study on patients with mild forms of relapsing-remitting multiple sclerosis (RR-MS) focused on these domains. To explore subtle neuropsychological changes in either the clinical or fMRI domain, we applied a multistep experimental design with increasing task complexity to investigate global brain activity, functional adaptation, and behavioral responses to typical cognitive processes related to attention and working memory. Fifteen patients with RR-MS (mean age 38 years, 22-49 years, 9 females, mean disease duration 5.9 years (SD = 3.6 years), mean Expanded Disability Status Scale score, 2.3 (SD = 1.3) but without reported cognitive impairment), and 15 age-matched healthy controls (HC; mean age, 34 years, 23-50 years, 6 women) participated. After a comprehensive neuropsychological assessment, participants performed different fMRI experiments testing attention and working memory. In the neuropsychological assessment, patients showed only subtle reduction in learning and memory abilities. In the fMRI experiments, both groups activated the brain areas typically involved in attention and working memory. HC showed a linear in- or decrease in activation paralleling the changing task complexity. Patients showed stronger activation change at the level of the simple tasks and a subsequent saturation effect of (de-)activation at the highest task load. These group/task interaction differences were found in the right parahippocampal cortex and in the middle and medial frontal regions. Our results indicate that, in MS, functional adaptation patterns can be found which precede clinical evidence of apparent cognitive decline.     

Specific language impairment with or without hyperactivity: neuropsychological evidence for frontostriatal dysfunction

A neuropsychological investigation of the association between specific language impairment (SLI) and hyperactivity was conducted on four groups of 6-year-old children. The groups, each consisting of five boys and five girls, were: children with SLI alone, hyperactivity alone, both SLI and hyperactivity, and neither disorder (controls). Cognitive functioning was examined using selected non-verbal tests from the Cambridge Neuropsychological Test Automated Battery. SLI was not associated with significantly reduced performance on any of the neuropsychological measures. However, hyperactivity was associated with deficits on a test of attentional set shifting previously demonstrated to be sensitive to frontostriatal dysfunction. Further, hyperactive children showed significantly reduced spatial spans on a test of spatial working memory thought to measure parietal lobe functioning. There were no substantial differences between the groups on tests of frontal lobe function except for reduced performance on a task of attention in the hyperactive group. There were no significant interactions between hyperactivity and SLI on any of the neuropsychological measures. The pattern of neuropsychological deficits shown by children with attention-deficit-hyperactivity disorder (ADHD) suggests relatively specific problems in inhibitory control of attentional selection. This cognitive deficit implicates brain areas including basal ganglia and ventro-lateral prefrontal cortical areas in ADHD, thus providing evidence for disruption of frontostriatal functional loops. SLI and hyperactivity can occur as comorbid syndromes or symptom complexes and this should be noted when interpreting results of tests measuring cognitive performance. The findings suggest that these two groups of disorders have different cognitive correlates.     

Neuropsychological performance in frontal lobe epilepsy.

The search for a special neuropsychological profile of frontal lobe epilepsy subjects (FLE) has so far led to inconclusive results. In this paper we compared the preoperative neuropsychological performance of FLE and temporal lobe epilepsy (TLE) subjects. We further investigated whether frontal lobe lesions of epileptogenic cause produce the same type of cognitive dysfunction as do tumours of the frontal lobe. Sixteen FLE subjects were compared to 16 TLE subjects as well as to a group of 10 subjects after the removal of frontal lobe tumors (TUM) and a healthy control group. A set of neuropsychological test measures routinely used for presurgical evaluation, an emotional conceptualization task and two associative learning tasks were administered. We found that subjects with frontal lobe damage were significantly impaired relative to controls on a wide range of cognitive functions independent of neurological cause. FLE subjects could hardly be discriminated from TLE subjects as both groups showed a similarly reduced level of neuropsychological performance. Our results demonstrate the devastating effect that frontal lobe epilepsy can have on cognitive functioning. Routinely used neuropsychological test measures lack the specificity to distinguish between frontal and temporal lobe epilepsy. Highly specialized measures are necessary to reveal differences.     

Assessment of executive dysfunction during activities of daily living in schizophrenia

Many neuropsychological studies have described deficits of memory and executive functions in patients with schizophrenia, and the severity of these deficits seems to be determinant in predicting the community outcome of these patients [Schizophr. Bull. 26 (2000) 119]. However, neuropsychological evaluation does not provide valuable information about how the cognitive deficits directly affect daily living, that is, which cognitive deficit affects which behavior. The present study aimed at determining whether executive dysfunction in schizophrenia could be directly measured by analyzing three activities of daily living (ADL), in addition to assessing the ecological validity of commonly used neuropsychological tests. Within specific ADL (choosing a menu, shopping the ingredients, cooking a meal), the sequences of behaviors that have been performed by 27 control subjects and 27 patients with schizophrenia were both analyzed by using a preset optimal sequence of behavior. When compared with control subjects, patients with schizophrenia showed more omissions when choosing the menu, more sequencing and repetitions errors during the shopping task, and more planning, sequencing, repetition and omission errors during the cooking task. These behavioral errors correlated significantly with negative, but not with positive symptoms of the patients. Furthermore, they also correlated with the poor performances on executive neuropsychological tests, especially those sensitive to shifting and sequencing abilities, but not with memory tests. These results suggest that executive deficits in schizophrenia may specifically affect ADL and that such deficits can be quantitatively assessed with a behavioral scale of action sequences.     

Association between homocysteine levels and cognitive profile in Alzheimer’s Disease

BackgroundGrowing evidence suggests that hyperhomocysteinemia (HHcy) constitutes a risk factor for Alzheimer’s Disease (AD). The impact of HHcy on cognitive functions has mainly been investigated using screening neuropsychological tests that provide general, unspecific measures of cognitive level. Since an association between HHcy and temporo-mesial atrophy has been documented, we predicted that a fine-grained analysis of neuropsychological performance should show stronger Hcy effects on memory scores than on other cognitive scores.ObjectiveTo determine the influence of Hcy level on cognitive profile evaluated with specific, sensitive neuropsychological tests in a wide AD cohort.Methods323 patients with AD were enrolled in a cross-sectional study and underwent a neuropsychological examination exploring several cognitive domains (memory, language, visuoperception, visuospatial abilities, executive function, constructional praxis, ideomotor praxis). The effects of Hcy levels and other risk factors (including cholesterol, smoking habits, triglycerides, apoEε4 allele) were analysed.ResultsGeneralized Linear Model detected a significant drop in performance with increasing Hcy in 6/19 measures of cognitive functions, namely, in memory performance tasks as well as in Luria’s motor planning test, with effect sizes ranging 1.4%–2.8% (Eta-squared), partialling out effects of other predictors.ConclusionsHHcy was associated with poor performance in short and long-term spatial and verbal memory more than with other cognitive dysfunctions. These results support the hypothesis that medial temporal networks might be vulnerable to HHcy, consistently with data from neuroimaging studies suggesting a link in AD between temporal atrophy and HHcy; the effect on Luria’s motor planning task suggests further involvement of frontal structures.     

The relationship between visual contrast sensitivity and neuropsychological performance in a healthy elderly sample

Visual acuity and contrast sensitivity are two visual domains affected by normal aging; however, the potential impact of well-documented changes in these abilities on neuropsychological assessment is relatively unstudied. The current study examined the relationship between these abilities and neuropsychological performance in a healthy, community-based elderly sample. Fifty-one individuals (Age: M = 79.6) were assessed for visual acuity and visual contrast sensitivity, and received a brief neuropsychological battery. Results indicated contrast sensitivity was significantly related to neuropsychological performance on visually based measures, but not auditory measures. Visual acuity was only weakly related to neuropsychological performance. Clinical implications for assessment of elderly individuals are discussed.     

Executive function subcomponents and their relations to everyday functioning in healthy older adults

Everyday functioning and its executive functioning cognitive correlates (i.e., switching, inhibition, and updating) were investigated in healthy older adults (HOAs) using multiple methods of functional status. In addition to whether computerized experimental tasks would better dissociate these subcomponents than neuropsychological measures of executive functioning, we were also interested in the contributions of both experimental and neuropsychological measures of executive function subcomponents to functional abilities. Seventy HOAs (45 young-old and 25 old-old) and 70 younger adults completed executive function and neuropsychological tests. In addition to self- and informant questionnaires of functional abilities, HOAs completed two performance-based measures. An aging effect was found on all executive function measures. Old-old older adults and their informants did not report more functional difficulties but demonstrated more difficulties on performance-based measures than did young-old participants. For the HOAs, after controlling for age and education, the neuropsychological measures of executive functioning, but not experimental measures, explained a significant amount of variance in the informant-report and both performance-based measures. Updating measures differentially predicted performance-based measures, while switching was important for questionnaire and performance-based measures. The contribution of executive functioning to functional status when measured with experimental measures specifically designed to isolate the executive subcomponent was not as strong as hypothesized. Further research examining the value of isolating executive function subcomponents in neuropsychological assessment and the prediction of functional abilities in older adults is warranted.