Confrontation naming does not add incremental diagnostic utility in MCI and Alzheimer's disease

Are subjective language complaints in memory clinic patients informative?

To diagnose mild cognitive impairment, it is crucial to understand whether subjective cognitive complaints reflect objective cognitive deficits. This question has mostly been investigated in the memory domain, with mixed results. Our study was one of the first to address it for language. Participants were 55-to-93-year-old memory clinic patients (n = 163). They filled in a questionnaire about subjective language and memory complaints and performed two language tasks (naming-by-definition and sentence comprehension). Greater language complaints were associated with two language measures, thus showing a moderate value in predicting language performance. Greater relative severity of language versus memory complaints was a better predictor, associated with three language performance measures. Surprisingly, greater memory complaints were associated with better naming, probably due to anosognosia in further disease progression or personality-related factors. Our findings highlight the importance of relative complaint severity across domains and, clinically, call for developing self-assessment questionnaires asking specific questions about multiple cognitive functions.

Language Markers of Dementia and Their Role in Early Diagnosis of Alzheimer's Disease: Exploring Grammatical and Syntactic Competence via Sentence Repetition

Background

Earlier research focuses primarily on the cognitive changes due to Alzheimer's disease (AD); however, little is known with regard to changes in language competence across the lifespan.

Objective

The present study aims to investigate the decline of language skills at the grammatical and syntactic levels due to changes in cognitive function.

Methods

We administered the Litmus Sentence Repetition Task (SRT) to 150 native speakers of Greek who fall into five groups: 1) young healthy speakers, 2) cognitively intact elder healthy speakers, 3) speakers with subjective cognitive impairment (SCI), 4) speakers with mild cognitive impairment (MCI); and 5) speakers with AD dementia at the mild/moderate stages. All participants underwent a physical and neurological examination and cognitive screening with a standardized neuropsychological battery to assess cognitive status comprehensively and evaluate aspects like working memory, executive function, attention and memory to appropriately classify them.

Results

The data analysis revealed that the SRT had high discriminatory value in the development of AD; specifically, both accuracy and grammaticality indices were related to cognitive decline. Additionally, syntax significantly affected the performance of speakers with structures such as clitics being particularly challenging and in most structures the performance of speakers with MCI drops significantly compared to speakers with SCI.

Conclusions

Linguistic indices revealed subtle early signs of cognitive decline that can be helpful in the early detection of AD, thus facilitating the clinical process offering support to language-based assessment tools such as sentence repetition, a non-invasive type of assessment to evaluate symptoms of AD.

Expanded Exploration of the Auditory Naming Test in Patients with Dementia

BACKGROUND

Auditory naming tests are superior to visual confrontation naming tests in revealing word-finding difficulties in many neuropathological conditions.

OBJECTIVE

To delineate characteristics of auditory naming most likely to reveal anomia in patients with dementia, and possibly improve diagnostic utility, we evaluated a large sample of patients referred with memory impairment complaints.

METHODS

Patients with dementia (N = 733) or other cognitive impairments and normal individuals (N = 69) were evaluated for frequency of impairment on variables of the Auditory Naming Test (ANT) of Hamberger & Seidel versus the Boston Naming Test (BNT).

RESULTS

Naming impairment occurred more frequently using the ANT total score (φ= 0.41) or ANT tip-of-the tongue score (TOT; φ= 0.19) but not ANT mean response time compared to the BNT in patients with dementia (p < 0.001). Significantly more patients were impaired on ANT variables than on the BNT in Alzheimer's disease (AD), vascular dementia (VaD), mixed AD/VaD, and multiple domain mild cognitive impairment (mMCI) but not in other dementias or amnestic MCI (aMCI). This differential performance of patients on auditory versus visual naming tasks was most pronounced in older, well-educated, male patients with the least cognitive impairment. Impaired verbal comprehension was not contributory. Inclusion of an ANT index score increased sensitivity in the dementia sample (92%). Poor specificity (41%) may be secondary to the inherent limitation of using the BNT as a control variable.

CONCLUSION

The ANT index score adds diagnostic utility to the assessment of naming difficulties in patients with suspected dementia.

Narrative impairment, white matter damage and CSF biomarkers in the Alzheimer's disease spectrum

BACKGROUND

Narrative discourse (ND) refers to one's ability to verbally reproduce a sequence of temporally and logically-linked events. Impairments in ND may occur in subjects with Amnestic Mild Cognitive Impairment (aMCI) and Alzheimer's Disease (AD), but correlates across this function, neuroimaging and cerebrospinal fluid (CSF) AD biomarkers remain understudied.

OBJECTIVES

We sought to measure correlates among ND, Diffusion Tensor Imaging (DTI) indexes and AD CSF biomarkers in patients within the AD spectrum.

RESULTS

Groups differed in narrative production (NProd) and comprehension. aMCI and AD presented poorer inference abilities than controls. AD subjects were more impaired than controls and aMCI regarding WB (p<0.01). ROIs DTI assessment distinguished the three groups. Mean Diffusivity (MD) in the uncinate, bilateral parahippocampal cingulate and left inferior occipitofrontal fasciculi negatively correlated with NProd. Changes in specific tracts correlated with T-tau/Aβ1-42 ratio in CSF.

CONCLUSIONS

AD and aMCI patients presented more ND impairments than controls. Those findings were associated with changes in ventral language-associated and in the inferior parahippocampal pathways. The latest were correlated with biomarkers' levels in the CSF.

METHODS

AD (N=14), aMCI (N=31) and Control (N=39) groups were compared for whole brain (WB) and regions of interest (ROI) DTI parameters, ND and AD CSF biomarkers.

Connected speech and language in mild cognitive impairment and Alzheimer's disease: A review of picture description tasks

INTRODUCTION

The neuropsychological profile of people with mild cognitive impairment (MCI) and Alzheimer's disease (AD) dementia includes a history of decline in memory and other cognitive domains, including language. While language impairments have been well described in AD dementia, language features of MCI are less well understood. Connected speech and language analysis is the study of an individual's spoken discourse, usually elicited by a target stimulus, the results of which can facilitate understanding of how language deficits typical of MCI and AD dementia manifest in everyday communication. Among discourse genres, picture description is a constrained task that relies less on episodic memory and more on semantic knowledge and retrieval, within the cognitive demands of a communication context. Understanding the breadth of evidence across the continuum of cognitive decline will help to elucidate the areas of strength and need in terms of using this method as an evaluative tool for both cognitive changes and everyday functional communication.

METHOD

We performed an extensive literature search of peer-reviewed journal articles that focused on the use of picture description tasks for evaluating language in persons with MCI or AD dementia. We selected articles based on inclusion and exclusion criteria and described the measures assessed, the psychometric properties that were reported, the findings, and the limitations of the included studies.

RESULTS

36 studies were selected and reviewed. Across all 36 studies, there were 1, 127 patients with AD dementia and 274 with MCI or early cognitive decline. Multiple measures were examined, including those describing semantic content, syntactic complexity, speech fluency, vocal parameters, and pragmatic language. Discriminant validity widely reported and distinct differences in language were observable between adults with dementia and controls; fewer studies were able to distinguish language differences between typically aging adults and those with MCI.

DISCUSSION

Our review shows that picture description tasks are useful tools for detecting differences in a wide variety of language and communicative measures. Future research should expand knowledge about subtle changes to language in preclinical AD and Mild Cognitive Impairment (MCI) which may improve the utility of this method as a clinically meaningful screening tool.

Connected Language in Late Middle-Aged Adults at Risk for Alzheimer's Disease

Connected language is often impaired among people with Alzheimer's disease (AD), yet little is known about when language difficulties first emerge on the path to a clinical diagnosis. The objective of this study was to determine whether individuals with psychometric (preclinical) evidence of amnestic mild cognitive impairment (pMCI) showed deficits in connected language measures. Participants were 39 pMCI and 39 cognitively healthy (CH) adults drawn from the Wisconsin Registry for Alzheimer's Prevention, who were matched for age, literacy, and sex. Participants completed a connected language task in which they described the Cookie Theft picture from the Boston Diagnostic Aphasia Examination. Language samples were analyzed across three language domains: content, syntactic complexity, and speech fluency. Paired t-tests were used to compare CH and pMCI groups on all variables, and Cohen's d effect sizes were calculated for each comparison. The CH and pMCI groups differed significantly on measures of content (e.g., CH group produced more semantic units, more unique words and had larger idea density, on average, than the pMCI group). The picture description findings are consistent with previous retrospective studies showing semantic language differences in adults with autopsy-confirmed AD. Given that these comparisons are between cognitively healthy and pMCI individuals (before a clinical MCI diagnosis), these findings may represent subtle language difficulty in spontaneous speech, and may be predictive of larger language changes over time.

Diagnostic Accuracy of Memory Measures in Alzheimer's Dementia and Mild Cognitive Impairment: a Systematic Review and Meta-Analysis

With an increasing focus on biomarkers in dementia research, illustrating the role of neuropsychological assessment in detecting mild cognitive impairment (MCI) and Alzheimer's dementia (AD) is important. This systematic review and meta-analysis, conducted in accordance with PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) standards, summarizes the sensitivity and specificity of memory measures in individuals with MCI and AD. Both meta-analytic and qualitative examination of AD versus healthy control (HC) studies (n = 47) revealed generally high sensitivity and specificity (≥ 80% for AD comparisons) for measures of immediate (sensitivity = 87%, specificity = 88%) and delayed memory (sensitivity = 89%, specificity = 89%), especially those involving word-list recall. Examination of MCI versus HC studies (n = 38) revealed generally lower diagnostic accuracy for both immediate (sensitivity = 72%, specificity = 81%) and delayed memory (sensitivity = 75%, specificity = 81%). Measures that differentiated AD from other conditions (n = 10 studies) yielded mixed results, with generally high sensitivity in the context of low or variable specificity. Results confirm that memory measures have high diagnostic accuracy for identification of AD, are promising but require further refinement for identification of MCI, and provide support for ongoing investigation of neuropsychological assessment as a cognitive biomarker of preclinical AD. Emphasizing diagnostic test accuracy statistics over null hypothesis testing in future studies will promote the ongoing use of neuropsychological tests as Alzheimer's disease research and clinical criteria increasingly rely upon cerebrospinal fluid (CSF) and neuroimaging biomarkers.

Cued and Un-Cued Semantic Category Fluency in Older Adults with Mild Cognitive Impairment

Background and Purpose

Patients with switching deficits reportedly benefit more from categorical cueing for semantic category fluency than do patients with clustering deficits. We explored the contribution of language ability and executive control on the performance of semantic category fluency in older adults with mild cognitive impairment (MCI) by examining the effects of categorical cueing on the task.

Methods

Order adults with MCI (n=10) and normal controls (n=25) were compared on two versions of a semantic fluency task: a standard, un-cued version (SF) and a version in which subjects were cued (C-SF) with 4 subordinated categories. The scores and error types of SF and C-SF tasks were analyzed between two groups. Also, the correlation among the SF task, the C-SF task, and the confrontation naming task were examined.

Results

The performance of the sematic fluency task improved when categorical cues were included in both groups. However, the normal group showed significantly more improvement than the MCI group. Self-repetition errors in the SF task and categorical errors in the C-SF task occurred most frequently. The normal group showed significantly more errors than the MCI group in the C-SF task. There was a positive correlation among the SF task, the C-SF task, and the confrontation naming task.

Conclusions

The results of the present study suggested that the MCI group has more difficulty in the semantic memory store rather than in the use of retrieval strategies. A combination of standard and cued semantic fluency tasks may help to confirm the underlying deficit of semantic fluency impairment.

Deficits in narrative discourse elicited by visual stimuli are already present in patients with mild cognitive impairment

Language batteries used to assess the skills of elderly individuals, such as naming and semantic verbal fluency, present some limitations in differentiating healthy controls from patients with amnestic mild cognitive impairment (a-MCI). Deficits in narrative discourse occur early in dementia caused by Alzheimer's disease (AD), and the narrative discourse abilities of a-MCI patients are poorly documented. The present study sought to propose and evaluate parameters for investigating narrative discourse in these populations. After a pilot study of 30 healthy subjects who served as a preliminary investigation of macro- and micro-linguistic aspects, 77 individuals (patients with AD and a-MCI and a control group) were evaluated. The experimental task required the participants to narrate a story based on a sequence of actions visually presented. The Control and AD groups differed in all parameters except narrative time and the total number of words recalled. The a-MCI group displayed mild discursive difficulties that were characterized as an intermediate stage between the Control and AD groups' performances. The a-MCI and Control groups differed from the AD group with respect to global coherence, discourse type and referential cohesion. The a-MCI and AD groups were similar to one another but differed from the Control group with respect to the type of words recalled, the repetition of words in the same sentence, the narrative structure and the inclusion of irrelevant propositions in the narrative. The narrative parameter that best distinguished the three groups was the speech effectiveness index. The proposed task was able to reveal differences between healthy controls and groups with cognitive decline. According to our findings, patients with a-MCI already present narrative deficits that are characterized by mild discursive difficulties that are less severe than those found in patients with AD.

Cognitive and emotional dysfunction in mild cognitive impairment

Although mild cognitive impairment (MCI) is a widely accepted construct both clinically and in the research literature, it remains a heterogeneous condition that varies in presentation and prognosis. This article first reviews the evolution of the diagnosis of MCI, followed by examination of pros and cons of cognitive assessments commonly used to assess for MCI. Emotional changes commonly seen in MCI are also reviewed. Finally, the relation between cognitive and emotional dysfunction is examined, including a discussion of specific psychological symptoms seen in subtypes of MCI, and how the presence of neuropsychiatric symptoms may affect the risk for progression to dementia.

The multilingual naming test in Alzheimer's disease: clues to the origin of naming impairments

The current study explored the picture naming performance of patients with Alzheimer’s disease (AD). First, we evaluated the utility of the multilingual naming test (MINT; Gollan et al., 2011), which was designed to assess naming skills in speakers of multiple languages, for detecting naming impairments in monolingual AD and amnestic mild cognitive impairment (MCI). If the MINT were sensitive to linguistic impairment in AD, using it in clinical practice might have advantages over using tests exclusively designed for English monolinguals. We found that the MINT can be used with both monolinguals and bilinguals: A 32-item subset of the MINT is best for distinguishing monolingual patients from controls, while the full MINT is best for assessing degree of bilingualism and language dominance in bilinguals. We then investigated the cognitive mechanisms underlying naming impairment in AD. To this end, we explored which MINT item characteristics best predicted performance differences between monolingual patients and controls. We found that contextual diversity and imageability, but not word frequency (nor words’ number of senses), contributed unique variance to explaining naming impairments in AD. These findings suggest a semantic component to the naming impairment in AD (modulated by names’ semantic richness and network size).

Distinguishing Alzheimer's disease from vascular dementia: an exploration of five cognitive domains

The disease process of Alzheimer's disease (AD) and Vascular Dementia (VaD) are dissimilar; however, the cognitive presentations may be difficult to distinguish as they may present in tandem or result in similar deficits despite different pathogenesis. This study examined the efficacy of memory, confrontational naming, visuoconstructional ability, processing speed, and executive functioning in differentiating AD from VaD. Delayed verbal memory, visuoconstructional ability, and confrontational naming as measured by WMS-R Logical Memory II, WAIS-R Block Design (BD), and Boston Naming Test, respectively, were most effective in discriminating between these two disorders. Results indicated AD was best classified by BD, and BD was the most sensitive to AD-related pathogenesis. Delayed memory and confrontational naming were highly implicated in each subtype, suggesting they are sensitive to each disease process, thus reducing the reliability of utilizing them as sole differentiating agents.

Heterogeneity in mild cognitive impairment: differences in neuropsychological profile and associated white matter lesion pathology

This study examined whether distinct neuropsychological profiles could be delineated in a sample with Mild Cognitive Impairment (MCI) and whether white matter lesion (WML) burden contributed to MCI group differences. A heterogeneous, clinical sample of 70 older adults diagnosed with MCI was assessed using cognitive scores, and WML was quantified using a semi-automated, volumetric approach on T2-weighted fluid-attenuated inversion recovery (FLAIR) images. Using cluster and discriminant analyses, three distinct groups (Memory/Language, Executive/Processing Speed, and Pure Memory) were empirically derived based on cognitive scores. Results also showed a dose dependent relationship of WML burden to MCI subgroup, with the Executive/Processing Speed subgroup demonstrating significantly higher levels of WML pathology when compared to the other subgroups. In addition, there was a dissociation of lesion type by the two most impaired subgroups (Memory/Language and Executive/Processing Speed) such that the Memory/Language subgroup showed higher periventricular lesion (PVL) and lower deep white matter lesion (DWML) volumes, whereas the Executive/Processing Speed demonstrated higher DWML and lower PVL volumes. Results demonstrate that distinct MCI subgroups can be empirically derived and reliably differentiated from a heterogeneous MCI sample, and that these profiles differ according to WML burden. Overall, findings suggest different underlying pathologies within MCI and contribute to our understanding of MCI subtypes.

Naming test of the Neuropsychological Assessment Battery: convergent and discriminant validity

This study investigated the convergent and discriminant validity of the naming subtest of the Neuropsychological Assessment Battery (NAB), a measure of word-finding. Seventy community-dwelling adults age 60 and above completed the NAB naming test (Forms 1 and 2), the Boston Naming Test (BNT), and other measures of verbal and visual memory, visuoperceptual skills, processing speed, and abstraction. The NAB naming test correlated highly with the BNT and with established measures of memory. The BNT correlated more strongly with education and with sex. The BNT correlated more strongly with a measure of visuoperceptual skills than the NAB naming test did, suggesting that visuoperception is more involved in the BNT. Divergent validity of the NAB naming was demonstrated by a lack of correlations with less-related measures. Findings suggest that the NAB naming test possesses convergent and divergent validity as a measure of word-finding.

Stability of different subtypes of mild cognitive impairment among the elderly over a 2- to 3-year follow-up period

BACKGROUND/AIMS

To investigate the longitudinal stability and progression of different subtypes of mild cognitive impairment (MCI) in older adults.

METHODS

We classified 217 individuals with no cognitive impairment (NCI), amnestic MCI (aMCI) based on a single test (aMCI-1) or multiple tests (aMCI-2+), nonamnestic MCI (naMCI) based on a single test (naMCI-1) or multiple tests (naMCI-2+), or amnestic + nonamnestic MCI (a+naMCI), using their baseline neuropsychological test scores, and performed annual follow-up evaluations for up to 3 years.

RESULTS

None of the subjects with aMCI-2+ reverted to normal during follow-up, with 50% of these subjects remaining stable and 50% worsening over time. Similarly, less than 20% of subjects with aMCI-2+ and a+naMCI reverted to NCI during the follow-up period, whereas 50% of aMCI-1 and 37% with naMCI-1 reverted to NCI during this same period.

CONCLUSION

Reversion to NCI occurs much more frequently when the diagnosis of MCI is based on the results of a single neuropsychological test than when it is based on the results of more memory tests. In epidemiological studies and clinical trials the diagnosis of MCI will likely be more stable if impairment on more than one test is required for amnestic and/or nonamnestic domains.

Diagnostic utility of sound naming in early Alzheimer's disease

While it is well known that picture naming (PN) is impaired in Alzheimer's disease (AD), sound naming (SN) has not been thoroughly investigated. We postulated that SN might be impaired more severely and earlier than PN, given the early involvement of the temporal cortex by AD-related pathology. SN and PN were assessed in 21 normal participants, 40 patients with mild cognitive impairment (MCI), and 27 patients in early stages of AD. Our results showed that SN accuracy and latency were more sensitive to advancing pathology in AD than PN accuracy and latency. SN was more useful and specific in distinguishing MCI patients from normal participants and therefore in potentially identifying the subset of MCI patients who already have impairment in more than one cognitive domain and may actually have incipient AD. These findings indicate a potential diagnostic utility of SN for early detection of the disease. Furthermore, even though most AD patients demonstrated more or less comparable impairment in both tasks, some were disproportionately impaired on SN and others were differentially impaired on PN. Future studies may be able to show that these discrepant groups correspond to patients with right and left hemisphere predominant AD, respectively.

Item analysis of three Spanish naming tests: a cross-cultural investigation

Neuropsychological evaluations conducted in the United States and abroad commonly include the use of tests translated from English to Spanish. The use of translated naming tests for evaluating predominately Spanish-speakers has recently been challenged on the grounds that translating test items may compromise a test's construct validity. The Texas Spanish Naming Test (TNT) has been developed in Spanish specifically for use with Spanish-speakers; however, it is unlikely patients from diverse Spanish-speaking geographical regions will perform uniformly on a naming test. The present study evaluated and compared the internal consistency and patterns of item-difficulty and -discrimination for the TNT and two commonly used translated naming tests in three countries (i.e., United States, Colombia, Spain). Two hundred fifty two subjects (136 demented, 116 nondemented) across three countries were administered the TNT, Modified Boston Naming Test-Spanish, and the naming subtest from the CERAD. The TNT demonstrated superior internal consistency to its counterparts, a superior item difficulty pattern than the CERAD naming test, and a superior item discrimination pattern than the MBNT-S across countries. Overall, all three Spanish naming tests differentiated nondemented and moderately demented individuals, but the results suggest the items of the TNT are most appropriate to use with Spanish-speakers. Preliminary normative data for the three tests examined in each country are provided.

Language performance in Alzheimer's disease and mild cognitive impairment: a comparative review

Mild cognitive impairment (MCI) manifests as memory impairment in the absence of dementia and progresses to Alzheimer's disease (AD) at a rate of around 15% per annum, versus 1-2% in the general population. It thus constitutes a primary target for investigation of early markers of AD. Language deficits occur early in AD, and performance on verbal tasks is an important diagnostic criterion for both AD and MCI. We review language performance in MCI, compare these findings to those seen in AD, and identify the primary issues in understanding language performance in MCI and selecting tasks with diagnostic and prognostic value.

Robust and conventional neuropsychological norms: diagnosis and prediction of age-related cognitive decline

The aim of the study was to compare the performance of Robust and Conventional neuropsychological norms in predicting clinical decline among healthy adults and in mild cognitive impairment (MCI). The authors developed Robust baseline cross sectional and longitudinal change norms from 113 healthy participants retaining a normal diagnosis for at least 4 years. Baseline Conventional norms were separately created for 256 similar healthy participants without follow-up. Conventional and Robust norms were tested in an independent cohort of longitudinally studied healthy (n=223), MCI (n=136), and Alzheimer's disease (AD, n=162) participants; 84 healthy participants declined to MCI or AD (NL-->DEC), and 44 MCI declined to AD (MCI-->AD). Compared to Conventional norms, baseline Robust norms correctly identified a higher proportion of NL-->DEC with impairment in delayed memory and attention-language domains. Both norms predicted decline from MCI-->AD. Change norms for delayed memory and attention-language significantly incremented baseline classification accuracies. These findings indicate that Robust norms improve identification of healthy individuals who will decline and may be useful for selecting at-risk participants for research studies and early interventions.

Subclinical naming errors in mild cognitive impairment: A semantic deficit?

Mild cognitive impairment (MCI) is the transitional stage between normal aging and Alzheimer’s disease (AD). Impairments in semantic memory have been demonstrated to be a critical factor in early AD. The Boston Naming Test (BNT) is a straightforward method of examining semantic or visuo-perceptual processing and therefore represents a potential diagnostic tool. The objective of this study was to examine naming ability and identify error types in patients with amnestic mild cognitive impairment (aMCI).

Development of the Texas Spanish Naming Test: a test for Spanish speakers

Neuropsychological assessment of Spanish speakers often involves translated versions of English measures, with limited validation data and potential bias due to cultural, educational, and linguistic differences. The Texas Spanish Naming Test (TNT), a 30-item confrontation naming test, was developed for Spanish speakers by systematically selecting culturally salient words. In a sample of 85 minimally educated Spanish speakers, the TNT demonstrated good internal consistency and convergent validity, and showed greater sensitivity than a translated version of the popular Boston Naming Test. Results support the clinical utility of the TNT when dementia among Spanish speakers is suspected.

Episodic memory and speed/attention deficits are associated with Alzheimer-typical CSF abnormalities in MCI

Mild cognitive impairment (MCI) is regarded as the prodromal stage of dementia disorders, such as Alzheimer's disease (AD).

OBJECTIVE

To compare the neuropsychological profiles of MCI subjects with normal concentrations of total tau (T-tau) and Abeta42 in CSF (MCI-norm) to MCI subjects with deviating concentrations of the biomarkers (MCI-dev). MCI-norm (N = 73) and MCI-dev (N = 73) subjects were compared to normal controls (N = 50) on tests of speed/attention, memory, visuospatial function, language and executive function.

RESULTS

MCI-norm performed overall better than MCI-dev, specifically on tests of speed and attention and episodic memory. When MCI-dev subjects were subclassified into those with only high T-tau (MCI-tau), only low Abeta42 (MCI-Abeta) and both high T-tau and low Abeta42 (MCI-tauAbeta), MCI-tauAbeta tended to perform slightly worse. MCI-tau and MCI-Abeta performed quite similarly.

CONCLUSIONS

Considering the neuropsychological differences, many MCI-norm probably had more benign forms of MCI, or early non-AD forms of neurodegenerative disorders. Although most MCI-dev performed clearly worse than MCI-norm on the neuropsychological battery, some did not show any deficits when compared to age norms. A combination of CSF analyses and neuropsychology could be a step toward a more exact diagnosis of MCI as prodromal AD.

Distinguishing between depression and dementia in older persons: neuropsychological and neuropathological correlates

Dementia and depression are frequently comorbid among older adult patients. Depression is related to cognitive decrement and can even represent the first signs of a neurodegenerative process. It can be difficult to distinguish depressed patients exhibiting the first signs of dementia from those whose cognition will improve with treatment. In this article, studies from the neuropsychological literature are reviewed that aid in accurate diagnosis and prognosis. Furthermore, the relationship between depression and dementia is explored by examining potential neurobiological mechanisms that may potentiate both syndromes in the context of the ongoing debate on depression as a prodrome and/or a risk factor for dementia. This article is concluded with suggestions for clinicians when deciding who to refer for neuropsychological assessment and with ideas for further research that might promote a better understanding of the complex association between depression and dementia during old age.

Normative data stratified for age, education, and gender on the Boston Naming Test

Stratified normative data for age, education, and gender are provided for the 60-item Boston Naming Test (BNT) on 1026 older participants ages 50-95 years using overlapping age ranges. Tables are presented that convert BNT raw scores to scaled scores and percentiles. Mild dementia cases were eliminated using a comprehensive cognitive battery. In a companion paper we found significantly poorer mean BNT scores and increasing variability with successively older age groups and decreasing educational levels indicating the need for demographically stratified normative data when determining an individual's degree of impairment. These norms should be clinically useful when assessing suspected dementia cases.

A cross-sectional study of the effects of age, education, and gender on the Boston Naming Test

The effects of age, education, and gender on visual confrontation naming using the 60-item Boston Naming Test (BNT) were studied in 1111 "normal" elderly (ages 50-101) and 61 younger adults (ages 20-49). Significantly poorer mean BNT scores and increasing variability (measured in standard deviations) were found with successively older age groups and with lower educational levels even after stratification on the demographic variables. There was a non-significant trend for males to score slightly higher than females. Age declines on the BNT were considerably greater for this cross-sectional data than for the longitudinal data we previously reported.

Analysis of brief language tests in the detection of cognitive decline and dementia

Lexical access difficulties are frequent in normal aging and initial stages of dementia.Verbal fluency tests are valuable to detect cognitive decline, evidencing lexico-semantic and executive dysfunction.

Neuropsychological differentiation of dementia with Lewy bodies from normal aging and Alzheimer's disease

We examined the diagnostic utility of selected neuropsychological measures in the differentiation of dementia with Lewy bodies (DLB) from normal aging and Alzheimer's disease (AD). Patients with DLB (n = 87), AD (n = 138), and a group of normal controls (n = 103) were recruited from the Mayo Alzheimer's disease patient registry and Alzheimer's Disease Research Center. Neuropsychological measures shown to have utility in previous studies were included in the analysis. The final multivariate logistic regression model distinguishing DLB from normal controls included Auditory Verbal Learning Test (AVLT) percent retention, Block Design, Trail Making Test-Part A, and Benton Visual Form Discrimination. This model has a sensitivity of 88.6% and specificity of 96.1%. The final multivariate logistic model distinguishing DLB from AD included Trail Making Part A, Boston Naming Test (BNT), AVLT percent retention, and copy of the Rey-Osterrieth Complex Figure. This model had a sensitivity of 83.3% and a specificity of 91.4%. AVLT and BNT had negative coefficients, indicating that lower scores decreased the likelihood of DLB relative to AD. These finding extend prior research suggesting a cognitive profile that can aid in the clinical diagnosis of DLB. Early attention and visual perceptual disturbance suggests DLB, while early impairment in memory and naming suggests AD.

Understanding reported cognitive dysfunction in older adults with cardiovascular disease

Older adults with cardiovascular disease (CVD) often report experiencing significant cognitive dysfunction in everyday life and exhibit deficits on neuropsychological testing. However, the relationship between subjective and objective cognitive dysfunction is inconsistent across studies and requires closer examination. Participants included 84 older adults with documented CVD and no history of neurological or severe psychiatric disorder. All participants underwent echocardiogram and neuropsychological assessment and completed self-report measures of perceived cognitive dysfunction, depression, and health-related quality of life. Results showed that concerns regarding distractibility and sustained attention were most common. Level of reported cognitive dysfunction was significantly related to depressive symptoms, quality of life, and performance on multiple cognitive tests. Exploratory regression analyses showed that depressive symptoms, physical health-related quality of life, and speeded sustained attention predicted reports of cognitive dysfunction, whereas demographic variables, cardiac output, and other cognitive tests did not. Should they be replicated, these findings suggest that reports of cognitive dysfunction in older adults with CVD largely reflect depressive symptoms and reduced quality of life.

Neuropsychology in Alzheimer's disease and other dementia research

PURPOSE OF REVIEW

This review describes a variety of neuropsychological dementia studies published between January 2004 and June 2005. In selecting articles for description in the present paper, our goal was not a comprehensive review of what is an enormous and growing literature, but rather to select and describe individual interesting studies from a sufficient range of dementia-related topics to permit illustration of some of the important questions for which a neuropsychological perspective aids in the understanding of dementias.

RECENT FINDINGS

Findings in the studies reviewed include a variety of different topics. Some of the themes include the following: (a) Alzheimer's disease is the most common cause of dementia, but a large body of research documents that there are important cognitive differences among various types of dementia, (b) the emerging research is also important in demonstrating the need for more sensitive clinical screening measures, (c) cognitive data are strongly predictive of functional decline, and (d) subtle declines in verbal learning appear to precede clinical Alzheimer's disease.

SUMMARY

Neuropsychological data are key to progress in understanding and developing more effective treatments for Alzheimer's disease and other dementia. For instance, efforts to identify early markers of dementia will be a key component to development of early intervention strategies.

A longitudinal study of confrontation naming in the "normal" elderly

The longitudinal effects of age on confrontation naming using the 60-item Boston Naming Test (BNT) were studied in 541 "normal" elderly (ages 50-99). For participants with at least 4 annual assessments (n = 238), 150 were followed for > or =6 years, 81 for > or =8 years, and 43 for > or =10 years. A small practice effect (0.21 words, p = 0.06) and moderately high test-retest reliability were found when comparing the first 2 assessments, which were 9-15 months apart (r = 0.76, n = 353). Reliable change index scores indicated that an annual decline of > or =4 points on the BNT is needed for a statistically reliable decline in an individual. A gradient in the mean annual rate of change on the BNT was found with improvement in the 50s age group, no change in the 60s age group, and decline in the 70s and 80s age groups. When projected over 10 years, the magnitudes of the mean changes were relatively small, that is, a 1-word improvement for participants in their 50s and a 1.3-word decline for participants in their 70s. These findings demonstrate that lexical retrieval as measured by a visual object confrontation naming task is generally well preserved in aging with only subtle decline in the 7th and 8th decades of age.

Criterion-referenced validity of a neuropsychological test battery: equivalent performance in elderly Hispanics and non-Hispanic Whites

This study examined the validity of the Spanish and English Neuropsychological Assessment Scales (SENAS) in comparison with clinical diagnosis of normal cognition versus cognitive impairment, not demented (CIND) versus demented in elderly Hispanics and Whites. Relationships between SENAS scales and diagnosis were essentially the same in Hispanics and Whites. Verbal memory measures were most strongly related, with more than 35% of the variance in these measures accounted for by diagnosis independent of effects of education, age, gender, and language. Diagnosis accounted for more than 10% of the variance (19% on average) in 11 of the 17 measures examined in this study. Logistic regressions showed that verbal memory was important both for distinguishing normal from CIND and CIND from demented. Object naming improved discrimination of CIND from demented beyond that of verbal memory alone. These results provide evidence of equivalent validity across Hispanics and Whites.