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Background and purpose Thirty per cent of amyotrophic lateral sclerosis (ALS) patients have non-motor symptoms, including executive and memory deficits. The in vivo anatomical basis of memory deficits in ALS has not been elucidated. In this observational study, brain atrophy in relation to memory function was investigated in ALS patients and controls. Methods Twenty-six ALS patients without dementia and 21 healthy volunteers matched for gender, age and education level underwent comprehensive neuropsychological evaluation and T1- and T2-weighted 3 T magnetic resonance imaging scanning of the brain. Grey and white matter brain volumes were analysed using voxel-based morphometry and age related white matter changes were assessed. The most frequently abnormal memory test (<2 SD below normative data corrected for age, gender and education) was correlated with regional brain volume variations by multiple regression analyses with age, gender and total grey matter volumes as covariates. Results Immediate and delayed story recall scores were abnormal in 23% of ALS patients and correlated to bilateral hippocampus grey matter volume ( r = 0.52 for both memory tests; P < 0.05; corrected for age, gender and total grey matter volume). This correlation was not found in healthy controls with similar age, education, anxiety and depression levels and white matter changes. Conclusions Prose memory impairment is a frequent finding in this cohort and is associated with hippocampus volume in ALS patients without dementia. These findings complement previous hippocampus changes in imaging studies in ALS and suggest involvement of the hippocampus in cognitive dysfunction of ALS. [ABSTRACT FROM AUTHOR]

Background. Abnormal levels of biomarkers in cerebrospinal fluid (CSF) and atrophy of medial temporal lobe (MTL) structures on magnetic resonance imaging (MRI) are being used increasingly to diagnose early Alzheimer's disease (AD). We evaluated the claim that these biomarkers can detect preclinical AD before behavioural (i.e. memory) symptoms arise. Method. We included all relevant longitudinal studies of CSF and MRI biomarkers published between January 2003 and November 2008. Subjects were not demented at baseline but some declined to mild cognitive impairment (MCI) or to AD during follow-up. Measures of tau and beta-amyloid in CSF, MTL atrophy on MRI, and performance on delayed memory tasks were extracted from the papers or obtained from the investigators. Results. Twenty-one MRI studies and 14 CSF studies were retrieved. The effect sizes of total tau (t-tau), phosphorylated tau (p-tau) and amyloid beta 42 (aβ42) ranged from 0.91 to 1.11. The effect size of MTL atrophy was 0.75. Memory performance had an effect size of 1.06. MTL atrophy and memory impairment tended to increase when assessed closer to the moment of diagnosis, whereas effect sizes of CSF biomarkers tended to increase when assessed longer before the diagnosis. Conclusions. Memory impairment is a more accurate predictor of early AD than atrophy of MTL on MRI, whereas CSF abnormalities and memory impairment are about equally predictive. Consequently, the CSF and MRI biomarkers are not very sensitive to preclinical AD. CSF markers remain promising, but studies with long follow-up periods in elderly subjects who are normal at baseline are needed to evaluate this promise. [ABSTRACT FROM AUTHOR]

Many studies have evaluated the utility of the Word Memory Test (WMT) as a symptom validity test. However, there is a lack of reference data for the WMT conventional memory subtests. The present study examined the demographic characteristics that influence performance on these subtests, in order to develop demographically corrected reference data. For this purpose, we administered the Dutch version of the WMT to 115 healthy Dutch controls, aged 20–80 years. Furthermore, we demonstrated the equivalence of the English and Dutch language versions of the WMT. Stepwise linear regression analyses of the combined Canadian and Dutch samples (N = 155) showed that the memory scores declined with increasing age. Participants with lower levels of education performed worse than more highly educated subjects. Reference data stratified by age and level of education are presented for use in research and clinical settings. [ABSTRACT FROM PUBLISHER]

Objectives: Chronic toxic encephalopathy (CTE) caused by long term occupational exposure to organic solvents is still a controversial disorder. Neuropsychological testing is the cornerstone for diagnosing the syndrome, but can be negatively influenced by motivational problems. In this nationwide study, we investigated the neuropsychological functioning and psychological symptoms of a large group of patients with suspected CTE, and ruled out alternative explanations for their complaints, including suboptimal performance due to insufficient effort. Methods: We studied participants with suspected CTE (n = 386) who were referred for further diagnosis to the Netherlands Centre of Occupational Diseases in the period 1998–2003 and who had completed the entire diagnostic protocol. Patients were excluded if there was the slightest suspicion that test performance had been negatively influenced by insufficient effort (n = 221), or if comprehensive assessment identified an alternative diagnosis (n = 80). Insufficient effort was defined by a combination of three indices. The neuropsychological test scores of the patient group (n = 85) were compared with those of a control group of building trade workers matched for sex, age, and educational level (n = 35). Results: The patient group had significantly more psychological complaints and performed significantly worse than the control group on tests of speed of information processing and memory and learning. However, only a small percentage of the patients had clearly abnormal scores for cognitive speed (9%) or memory (8%). Attention, verbal abilities, and constructional functions were not disturbed. Exposure duration and cognitive complaints were significantly correlated, whereas the correlation between exposure duration and neuropsychological domain scores was not significant. Conclusions: Insufficient effort was present in a substantial part of the patient group. After minimising the likelihood that insufficient effort negatively influenced neuropsychological scores, we still found neuropsychological deficits in speed of cognitive processing and memory; however, these scores were clearly abnormal only in a minority of patients with suspected CTE. Screening instruments should focus on these domains. [ABSTRACT FROM AUTHOR]

Background: The seven minute screen (7M5) is a compilation of the temporal orientation test, enhanced cued recall, clock drawing, and verbal fluency. It has been shown to be useful For detecting Alzheimer's disease in a population of patients with memory complaints. Objective: To assess the predictive validity of the 7M5 for various types of dementia, and the influence of depression and other psychiatric conditions on 7MS scores. Setting: Multicentre: secondary referral sites across the Netherlands. Subjects: 542 patients with various types of dementia or depression, together with 4.5 healthy controls. Results: Alzheimer's disease was diagnosed in 177 patients, other types of dementia in 164. The sensitivity of the 7MS for Alzheimer's disease was 92.9% with a specificity of 93.5%. For other types of dementia the sensitivity was 89.4% and the specificity 93.5%. Cognitive abnormalities were found in 71% of the patients with depression (n = 31). The mean (SD) duration of administration of the 7M5 was 12.4 (4.6) minutes, range 8 to 22, depending on dementia severity. Conclusions: The 7MS is a useful screening tool for discriminating patients with dementia from cognitively intact patients. This not only applies to Alzheimer's disease but also to other types of dementia. Specificity with respect to depression was lower for the 7M5 than for the MMSE. [ABSTRACT FROM AUTHOR]

Background: Population studies indicate that subjective memory complaints by elderly people are correlated with cognitive performance. These complaints have some predictive power regarding the development of dementia. The present study attempted to replicate this finding, and investigated which variables determine subjective memory complaints.Method: Participants in the Amsterdam Study of the Elderly (n = 2114; 65-84 years of age), who were not demented and had a normal MMSE score (> 23) at baseline, were re-examined after four years. Subjective complaints were measured using a previously developed scale. Dementia and depression were measured using the Geriatric Mental State Schedule (GMS). Premorbid intelligence was measured by the Dutch Adult Reading Test (DART).Results: Memory complaints at baseline contributed a small but significant amount of diagnostic information with respect to the prediction of future dementia. Depressive symptoms at baseline had no predictive value when these memory complaints were accounted for. Subjective memory complaints were associated with depression, baseline MMSE score, and premorbid intelligence.Conclusions: Subjective memory complaints are not just secondary to depression, but in part reflect realistic self-observations of cognitive decline. [ABSTRACT FROM AUTHOR]

Objective We developed a cloud-based platform, Philips Intellispace Cognition (ISC), containing tablet-based versions of conventional cognitive tests. We investigated the battery's sensitivity for subtle cognitive impairment in a mixed clinical sample. Method The sample consisted of 221 healthy participants and 98 traumatic brain injury (TBI) and stroke patients who all scored above the MMSE-2 cutoff of 24, but reported subjective cognitive complaints. All completed the following ISC tests: Phonetic Fluency; Semantic Fluency; Trail-Making; Stroop; O-Cancellation; Star-Cancellation; Digit Span; Rey Auditory Verbal Learning; Rey-Osterrieth Complex Figure. We used ROC analyses to investigate our ability to distinguish the patient and healthy samples. Specifically, we assessed the area under the curve (AUC), where a value of.50 indicates random classification and 1 indicates perfect distinguishability. To this end, we compared sensitivity of cognitive domain scores distilled from the ISC tests (using confirmatory factor analysis) with the sensitivity of MMSE-2 scores. The cognitive domains were executive functioning, processing speed, working memory, memory, and visuospatial ability. Results The AUC of the MMSE-2 was.46, as expected given the fact that all patients scored above the cut-off. The AUCs of the model domain scores ranged from.56 to.73. The differences between these AUCs and the MMSE AUC were all significant (ps ≤.004), except for visuospatial ability (p =.070). Conclusions The ISC test battery was able to pick up on cognitive impairment in a mixed clinical sample consisting of patients that all scored normally on the MMSE-2. These findings show the usefulness of the digital platform in clinical practice. [ABSTRACT FROM AUTHOR]

Objective Following recent (meta-)analyses showing that the Cattell-Horn-Carroll (CHC) model outperforms traditional neuropsychological models of cognition, we investigated the relative performance of the traditional neuropsychological model (TNM) of cognitive functioning and the CHC model using the digital Philips IntelliSpace Cognition (ISC) test battery. Method The ISC battery consists of 11 conventional cognitive tests, which were administered to 221 healthy participants. We used confirmatory factor analysis (CFA) to map outcome measures to cognitive domains. Both models contained processing speed, working memory, memory, and visuospatial ability. TNM included executive functioning consisting of TMT B, Stroop interference, and Phonetic and Semantic Fluency. In the CHC model, these outcome measures were distributed over processing speed and a word fluency domain. The models' fit was compared through Vuong test for non-nested models. Results Both models were a good fit (TNM: χ2(64) = 91.95, p =.013, CFI =.971, RMSEA =.044; CHC: χ2(64) = 83.66, p =.050, CFI =.979, RMSEA =.037). The Vuong test showed that the models could be significantly distinguished based on the observed data, ω2 = 0.21, p <.001. However, the non-nested likelihood ratio test did not offer evidence that either model was a better fit, z = -0.61, p =.727. The 95% confidence interval of the AIC difference contained zero [-18.60, 35.20]. Conclusions Recent findings showing that the CHC model outperforms the TNM are not corroborated by our findings. Instead, both models captured the data equally well, suggesting that the two theoretical frameworks are not necessarily mutually exclusive. [ABSTRACT FROM AUTHOR]