Sex-based dyad differences on informant reports of participants' daily functioning.

Functional assessment in neurocognitive evaluation is often provided via informant reports. These subjective reports can vary based on the characteristics of informants and their relationships with participants, such as informant sex. However, whether informant sex intersects with participant sex to impact subjective ratings of participants' daily functioning, and whether such effects mirror observed patterns in neuropsychological performance, has not been adequately examined with ethnoracially diverse samples. We examined differences among participant-informant sex-based dyads on subjective informant reports of participants' daily functioning (assessed via the Functional Activities Questionnaire [FAQ]), and whether any observed differences on reported functioning corresponded to differences in objective participant performance on neuropsychological performance, among middle-aged and older Hispanic/Latino (n = 543), non-Hispanic Black (NHB; n = 1030), and non-Hispanic White (NHW; n = 5356) adults in the National Alzheimer's Coordinating Center cohort (n = 6929). Analysis of covariance (ANCOVA) tests revealed significant dyad differences on FAQ scores in the NHB (p<.001) and NHW subsamples (p<.05), but not in the Hispanic/Latino subsample (p>.05). For the Hispanic/Latino and NHB subsamples, ANCOVA tests revealed no significant effects of dyad on neuropsychological performance (ps>.01), whereas for the NHW subsample, ANCOVA tests revealed significant dyad differences on performance in multiple cognitive domains (ps<.01). Nevertheless, the pattern of dyad differences on neuropsychological performance did not mirror the pattern of observed differences on FAQ scores in the NHW subsample. Findings and their implications, including potential contributions of other informant characteristics on observed dyad differences on reported functioning, are discussed.

Characterizing cognitive profiles in diverse middle-aged and older Hispanics/Latinos: Study of Latinos-Investigation of Neurocognitive Aging (HCHS/SOL).

Introduction: We investigated cognitive profiles among diverse, middle-aged and older Hispanic/Latino adults in the Study of Latinos-Investigation of Neurocognitive Aging (SOL-INCA) cohort using a cross-sectional observational study design. Methods: Based on weighted descriptive statistics, the average baseline age of the target population was 56.4 years, slightly more than half were women (54.6%), and 38.4% reported less than a high school education. We used latent profile analysis of demographically adjusted z scores on SOL-INCA neurocognitive tests spanning domains of verbal memory, language, processing speed, and executive function. Results: Statistical fit assessment indices combined with clinical interpretation suggested five profiles: (1) a Higher Global group performing in the average-to-high-average range across all cognitive and instrumental activity of daily living (IADL) tests (13.8%); (2) a Higher Memory group with relatively high performance on memory tests but average performance across all other cognitive/IADL tests (24.6%); (3) a Lower Memory group with relatively low performance on memory tests but average performance across all other cognitive/IADL tests (32.8%); (4) a Lower Executive Function group with relatively low performance on executive function and processing speed tests but average-to-low-average performance across all other cognitive/IADL tests (16.6%); and (5) a Lower Global group performing low-average-to-mildly impaired across all cognitive/IADL tests (12.1%). Discussion: Our results provide evidence of heterogeneity in the cognitive profiles of a representative, community-dwelling sample of diverse Hispanic/Latino adults. Our analyses yielded cognitive profiles that may assist efforts to better understand the early cognitive changes that may portend Alzheimer's disease and related dementias among diverse Hispanics/Latinos. Highlights: The present study characterized cognitive profiles among diverse middle-aged and older Hispanic/Latino adults.Latent profile analysis of neurocognitive test scores was the primary analysis conducted.The target population consists of middle-aged and older Hispanic/Latino adults enrolled in the Hispanic Community Health Study/Study of Latinos and ancillary Study of Latinos - Investigation of Neurocognitive Aging.

Normative data for the Digit Symbol Substitution for diverse Hispanic/Latino adults: Results from the Study of Latinos-Investigation of Neurocognitive Aging (SOL-INCA).

INTRODUCTION: Executive functioning and processing speed are crucial elements of neuropsychological assessment. To meet the needs of the Hispanic/Latino population, we aimed to provide normative data for the Digit Symbol Substitution (DSS) test. METHODS: The target population for the Study of Latinos-Investigation of Neurocognitive Aging included six heritage backgrounds (n = 6177). Average age was 63.4 ± 8.3 years, 54.5% were female, and mean education was 11.0 ± 4.7 years. Participants were administered the DSS as part of a larger battery. Heritage-adjusted DSS scores, and percentile cut-points were created using survey-adjusted regression and quantile regression models. RESULTS: Age, education, sex, heritage, and language preference were associated with DSS scores. DISCUSSION: Significant correlates of DSS performance should be considered when evaluating cognitive performance. Representative DSS norms for Hispanics/Latinos will advance assessment and accuracy of neurocognitive disorder diagnosis in clinical practice. To facilitate interpretation, we provide norms to reduce test biases and developed an online dashboard. Highlights: Normative data for the Digit Symbol Substitution (DSS) for diverse Hispanic/Latino adults: Results from the Study of Latinos-Investigation of Neurocognitive Aging (SOL-INCA) This study is the first to develop norms for the DSS test across four regions of the United States.Factors such as age, education, sex, and Hispanic/Latino heritage and language preference are associated with differences in executive functioning and information processing speed.We created norms and an online dashboard (https://solincalab.shinyapps.io/dsst_shiny/) providing an easily accessible tool to evaluate processing speed and executive functioning in Hispanic/Latino adults.

Informant sex/gender moderates associations between reported functioning and memory performance in Mexican American adults.

Objective: In neuropsychological evaluations, assessing cognitive functioning is often achieved using objective neuropsychological measures, whereas subjective informant reports are typically obtained to determine manifest daily functioning. Informant reports of participant functioning and their associations with objective participant performance on neuropsychological testing have been shown to vary based on informant characteristics. However, associations among informant characteristics, reported functioning, and neuropsychological performance have not been adequately examined with Mexican American or other Hispanic/Latino samples, despite these populations' disproportionately higher rates of dementia due to Alzheimer's disease and related disorders. Method: We examined associations of informant characteristics with informant reports of participant functioning (assessed via the Functional Activities Questionnaire [FAQ]), and potential moderating effects of these characteristics on associations between reported functioning and participant performance on neuropsychological testing, for Mexican American adult participants in the National Alzheimer's Coordinating Center cohort (n = 294). Results: Female informants reported significantly worse participant functioning compared to male informants (p = .035, r = .126). Moreover, significant associations between reported functioning and memory performance were observed for participants with female informants, but not for those with male informants (p = .024, r = .138). Higher levels of informant education were associated with significantly worse participant functioning (p = .011, r = .151). However, informant education did not moderate associations between reported functioning and neuropsychological performance (ps > .05). Conclusions: Compared to male informants, female informants may provide subjective reports of Mexican American participant functioning that more closely corroborate objective participant performance in memory.

Informant Characteristics Influence Reports of Participant Functioning and their Associations with Neuropsychological Performance in Non-Hispanic Black Adults.

OBJECTIVE: Assessing one's functional capacity-in addition to neuropsychological performance-is essential for determining neurocognitive status, and functional assessment is often provided via informant report. Although informant characteristics have been shown to influence reports of participant functioning, the degree to which they moderate relationships between reported functioning and participant performance on neuropsychological testing is unclear. Moreover, associations among informant characteristics, reported functioning, and neuropsychological performance have not been adequately examined with non-Hispanic Black (NHB) samples, despite this population's disproportionately high risk of Alzheimer's disease and related dementias. METHOD: In this cross-sectional observational study, we examined the influence of informant characteristics on informant reports of participant functioning (assessed via the Functional Activities Questionnaire [FAQ]) and associations between reported functioning and participant performance on neuropsychological testing, among NHB adult participants in the National Alzheimer's Coordinating Center cohort (n = 1024). RESULTS: Informants who were younger, female, more educated, knew participants longer, or lived with participants reported poorer participant functioning (p < .001). However, younger (vs. older) informants provided reports of functioning that were more predictive of visuoconstructional ability and visual memory, and male (vs. female) informants provided reports of functioning that were more predictive of verbal memory, visuoconstructional ability and visual memory, and language (ps < .001). CONCLUSIONS: Within the context of neurocognitive evaluations of NHB participants, informant characteristics may influence subjective reports of participants' functioning and the extent to which reported functioning corroborates objective participant performance on neuropsychological testing.

Source recognition discriminability impairment in Huntington's versus Alzheimer's disease: Evidence from the CVLT-3.

Research suggests that individuals with Huntington's disease (HD) perform better than individuals with Alzheimer's disease (AD) on the California Verbal Learning Test (CVLT) Yes/No Recognition trial. However, those with HD have been shown to have deficits comparable to those with AD on the Source Recognition Discriminability (RD) index (which assesses the ability to distinguish between List A targets and List B distractors), suggesting that HD may involve selective impairment in aspects of yes/no recognition that rely on source memory. However, whether individuals with HD and AD show comparable deficits on Source RD across stages of dementia severity has not been adequately investigated. We examined performance on the CVLT-3 List A vs. List B RD index in individuals with HD or AD and mild or moderate dementia. Among individuals with mild dementia, scores were higher in the HD versus AD group, whereas among individuals with moderate dementia, scores were comparable between the HD and AD groups; this corresponded to differential performance across dementia stages among individuals with HD, but not AD. The present findings suggest that, relative to AD, HD may be associated with disproportionate decline in aspects of yes/no recognition that rely on source memory.

Longitudinal Patterns of Alcohol Use Following Traumatic Brain Injury in an Active Duty and Young Veteran Military Sample: A VA TBI Model Systems Study.

OBJECTIVE: To describe alcohol use among younger military active duty service members and veterans (SMVs) in the first 5 years after traumatic brain injury (TBI) and examine whether differential alcohol use patterns emerge as a function of brain injury severity and active duty service at time of injury. SETTING: Veterans Affairs (VA) Polytrauma Rehabilitation Centers (PRCs). PARTICIPANTS: In total, 265 SMVs enrolled in the VA Traumatic Brain Injury Model Systems (TBIMS) PRC national database. Participants sustained a TBI of any severity level; received inpatient care at a PRC within 1 year of injury; were younger than 40 years; and completed survey interviews or questionnaires regarding their pre- and postinjury alcohol use for at least 3 of 4 time points (preinjury, postinjury years 1, 2, and 5). MAIN MEASURES: Self-reported alcohol use, defined as amount of weekly consumption and endorsement of binge drinking. Participant information related to demographics, injury, TBI severity, active duty status, mental health treatment, and FIM (Functional Independence Measure) total scores was also obtained to examine impact of these as covariates in the analyses. RESULTS: Alcohol use generally increased following an initial period of reduced consumption for SVMs with moderate-to-severe TBI. Individuals with mild TBI showed an opposite trend, with an initial period of increased use, followed by a decline and return to baseline levels in the long term. However, alcohol use did not significantly differ over time within this subsample after adjusting for covariates. CONCLUSIONS: The current study identified longitudinal alcohol use among a young, military/veteran cohort with a history of TBI, an at-risk population for problematic alcohol use. Patterns of self-reported alcohol consumption suggest the time frame of 2 to 5 years postinjury may be a critical window of opportunity for further intervention to maintain lowered levels of alcohol use, particularly among SVMs with moderate-to-severe TBI.

Diagnostic accuracy and differential associations between ratings of functioning and neuropsychological performance in non-Hispanic Black and White older adults.

ObjectiveWe recently demonstrated that relative to consensus-based methods, actuarial methods may improve diagnostic accuracy across the continuum of cognitively normal (CN), mild cognitive impairment (MCI), and dementia in the overall National Alzheimer's Coordinating Center (NACC) cohort. However, the generalizability and comparative utility of current methods of diagnosing MCI and dementia due to Alzheimer's disease and related disorders (ADRD) are significantly understudied in non-Hispanic Black (NHB) older adults. Thus, we extended our previous investigation to more specifically explore the utility of consensus-based and actuarial diagnostic methods in NHB older adults.Method: We compared baseline consensus and actuarial diagnostic rates, and associations of ratings of functioning with neuropsychological performance and diagnostic outcomes, in NHB (n = 963) and non-Hispanic White (NHW; n = 4577) older adults in the NACC cohort.Results: 60.0% of the NHB subsample, versus 29.2% of the NHW subsample, included participants who met actuarial criteria for MCI despite being classified as CN or impaired-not-MCI per consensus. Additionally, associations between ratings of functioning and neuropsychological performance were less consistent in NHB participants than in NHW participants.Conclusions: Our results provide evidence of differential degrees of association between reported functioning and neuropsychological performance in NHB and NHW older adults, which may contribute to racial group differences in diagnostic rates, and prompt consideration of the strengths and weaknesses of consensus-based and actuarial diagnostic approaches in assessing neurocognitive functioning in NHB older adults.

Pathological functional impairment: Neuropsychological correlates of the shared variance between everyday functioning and brain volumetrics.

Objective: Given that several non-cognitive factors can contribute to difficulties with everyday functioning, examining the extent to which cognition is associated with brain-related changes in everyday functioning is critical to accurate characterization of cognitive disorders. In this study, we examined neuropsychological correlates of the shared variance between everyday functioning and pathological indicators of cognitive aging using MRI brain volumetrics. Participants and methods: Participants were 600 adults aged 55 and older without dementia [432 cognitively normal; 168 mild cognitive impairment (MCI)] from the National Alzheimer's Coordinating Center cohort who underwent neuropsychological testing, informant-rated everyday functioning, and brain MRI scanning at baseline. The shared variance between everyday functioning and brain volumetrics (i.e., hippocampal volume, white matter hyperintensity volume) was extracted using the predicted value from multiple regression. The shared variance was used as an indicator of pathological everyday functional impairment. The residual variance from the regression analysis was used to examine functional reserve. Results: Larger white matter hyperintensity volumes (p = 0.002) and smaller hippocampal volumes (p < 0.001) were significantly correlated with worse informant-rated everyday functioning. Among individuals with MCI, worse performances on delayed recall (p = 0.013) and category fluency (p = 0.012) were significantly correlated with pathological functional impairment in multiple regression analysis. In the cognitively normal group, only worse auditory working memory (i.e., digit span backward; p = 0.025) significantly correlated with pathological functioning. Functional reserve was inversely related to anxiety (p < 0.001) in the MCI group and was associated with depressive symptoms (p = 0.003) and apathy (p < 0.001) in the cognitively normal group. Conclusion: Subtle brain-related everyday functioning difficulties are evident in MCI and track with expected preclinical Alzheimer's disease cognitive phenotypes in this largely amnestic sample. Our findings indicate that functional changes occur early in the disease process and that interventions to target neuropsychiatric symptoms may help to bolster functional reserve in those at risk.

Data-Driven vs Consensus Diagnosis of MCI: Enhanced Sensitivity for Detection of Clinical, Biomarker, and Neuropathologic Outcomes.

BACKGROUND AND OBJECTIVES: Given prior work demonstrating that mild cognitive impairment (MCI) can be empirically differentiated into meaningful cognitive subtypes, we applied actuarial methods to comprehensive neuropsychological data from the University of California San Diego Alzheimer's Disease Research Center (ADRC) in order to identify cognitive subgroups within ADRC participants without dementia and to examine cognitive, biomarker, and neuropathologic trajectories. METHODS: Cluster analysis was performed on baseline neuropsychological data (n = 738; mean age 71.8). Survival analysis examined progression to dementia (mean follow-up 5.9 years). CSF Alzheimer disease (AD) biomarker status and neuropathologic findings at follow-up were examined in a subset with available data. RESULTS: Five clusters were identified: optimal cognitively normal (CN; n = 130) with above-average cognition, typical CN (n = 204) with average cognition, nonamnestic MCI (naMCI; n = 104), amnestic MCI (aMCI; n = 216), and mixed MCI (mMCI; n = 84). Progression to dementia differed across MCI subtypes (mMCI > aMCI > naMCI), with the mMCI group demonstrating the highest rate of CSF biomarker positivity and AD pathology at autopsy. Actuarial methods classified 29.5% more of the sample with MCI and outperformed consensus diagnoses in capturing those who had abnormal biomarkers, progressed to dementia, or had AD pathology at autopsy. DISCUSSION: We identified subtypes of MCI and CN with differing cognitive profiles, clinical outcomes, CSF AD biomarkers, and neuropathologic findings over more than 10 years of follow-up. Results demonstrate that actuarial methods produce reliable cognitive phenotypes, with data from a subset suggesting unique biological and neuropathologic signatures. Findings indicate that data-driven algorithms enhance diagnostic sensitivity relative to consensus diagnosis for identifying older adults at risk for cognitive decline.

Revisiting total recognition discriminability in Huntington's and Alzheimer's disease: New insights from the CVLT-3.

The original and second editions of the California Verbal Learning Test (CVLT) used nonparametric and parametric methods, respectively, to assess Total Recognition Discriminability (RD). In a previous study, we found evidence that the nonparametric formula may be more sensitive than the parametric formula to high false positive (FP) rates and provide more accurate assessments of yes/no recognition in neurodegenerative populations prone to high FP rates, including Alzheimer's disease (AD). In the present study, we extended our investigation to examine the utility of CVLT-3 nonparametric and parametric Total RD indices in the assessment and comparison of yes/no recognition in individuals with Huntington's disease (HD) and AD in mild and moderate stages of dementia. Findings suggested that the CVLT-3 nonparametric Total RD index was more sensitive than the parametric index to HD and AD differences in yes/no recognition across mild and moderate stages of dementia. Additionally, group differences on total FP errors were more closely mirrored by group differences on the nonparametric Total RD index. The present results bolster our previous findings and highlight the utility of examining nonparametric (in addition to parametric) Total RD on the CVLT-3 in assessments of yes/no recognition involving clinical populations prone to high FP rates.

Cohort differences on the CVLT-II and CVLT3: Evidence of a negative Flynn effect on the attention/working memory and learning trials.

OBJECTIVE: Although cohort effects on IQ measures have been investigated extensively, studies exploring cohort differences on verbal memory tests, and the extent to which they are influenced by socioenvironmental changes across decades (e.g. educational attainment; ethnic makeup), have been limited. METHOD: We examined differences in performance between the normative samples of the CVLT-II from 1999 and the CVLT3 from 2016 to 2017 on the immediate- and delayed-recall trials, and we explored the degree to which verbal learning and memory skills might be influenced by the cohort year in which norms were collected versus demographic factors (e.g. education level). RESULTS: Multivariate analysis of variance tests and follow-up univariate tests yielded evidence for a negative cohort effect (also referred to as negative Flynn effect) on performance, controlling for demographic factors (p = .001). In particular, findings revealed evidence of a negative Flynn effect on the attention/working memory and learning trials (Trial 1, Trial 2, Trial 3, Trials 1-5 Total, List B; ps < .007), with no significant cohort differences found on the delayed-recall trials. As expected, education level, age group, and ethnicity were significant predictors of CVLT performance (ps < .01). Importantly, however, there were no interactions between cohort year of norms collection and education level, age group, or ethnicity on performance. CONCLUSIONS: The clinical implications of the present findings for using word list learning and memory tests like the CVLT, and the potential role of socioenvironmental factors on the observed negative Flynn effect on the attention/working memory and learning trials, are discussed.

Evidence for the Utility of Actuarial Neuropsychological Criteria Across the Continuum of Normal Aging, Mild Cognitive Impairment, and Dementia.

BACKGROUND: Research suggests that actuarial neuropsychological criteria improve the accuracy of mild cognitive impairment (MCI) diagnoses relative to conventional diagnostic methods. OBJECTIVE: We sought to examine the utility of actuarial criteria relative to consensus diagnostic methods used in the National Alzheimer's Coordinating Center (NACC) Uniform Data Set (UDS), and more broadly across the continuum of normal aging, MCI, and dementia. METHODS: We compared rates of cognitively normal (CN), MCI, and dementia diagnoses at baseline using actuarial versus consensus diagnostic methods in 1524 individuals from the NACC UDS. RESULTS: Approximately one-third (33.59%) of individuals diagnosed as CN and more than one-fifth (22.03%) diagnosed with dementia based on consensus methods, met actuarial criteria for MCI. Many participants diagnosed with MCI via consensus methods also appeared to represent possible diagnostic errors. Notably, the CNa/CNc group (i.e., participants diagnosed as CN based on both actuarial [a] and consensus [c] criteria) had a lower proportion of apolipoprotein E ɛ4 carriers than the MCIa/MCIc group, which in turn had a lower proportion of ɛ4 carriers than the dementia (Dem)a/Demc group. Proportions of ɛ4 carriers were comparable between the CNa/CNc and CNa/MCIc, MCIa/MCIc and MCIa/CNc, MCIa/MCIc and MCIa/Demc, and Dema/Demc and Dema/MCIc groups. These results were largely consistent with diagnostic agreement/discrepancy group comparisons on neuropsychological performance. CONCLUSION: The present results extend previous findings and suggest that actuarial neuropsychological criteria may enhance diagnostic accuracy relative to consensus methods, and across the wider continuum of normal aging, MCI, and dementia. Findings have implications for both clinical practice and research.

Identification of Subtle Verbal Memory Deficits in Premanifest Huntington Disease Using the California Verbal Learning Test.

BACKGROUND: Verbal memory impairment in individuals with Huntington disease (HD) is well-documented; however, the nature and extent of verbal memory impairment in individuals with premanifest HD (pre-HD) are less understood. OBJECTIVE: To evaluate verbal memory function in individuals with pre-HD by comparing their performance on the California Verbal Learning Test to that of individuals with a clinical diagnosis of HD and that of a demographically similar group of adults with no family history of, or genetic risk for, HD, thereby reducing possible complications of psychiatric difficulties commonly experienced by individuals who are at risk for HD but are gene negative. METHODS: Participant groups included 77 adults with a diagnosis of HD, 23 premanifest gene carriers for HD (pre-HD), and 54 demographically similar, healthy adults. The California Verbal Learning Test-Second Edition (CVLT-II) was used to evaluate the participants' immediate and delayed recall, recognition, learning characteristics, errors, and memory retention. RESULTS: The pre-HD group performed significantly worse than the healthy group, yet significantly better than the HD group, on Short and Long Delay Recall (Free and Cued) and Recognition Discriminability. On Total Immediate Recall, Learning Slope, Semantic Clustering, and Intrusions, the pre-HD group performed similarly to the healthy group and significantly better than the HD group. None of the groups differed in their performance on Repetitions and a measure of retention. CONCLUSIONS: Subtle memory deficits can be observed during the premanifest stage of HD with use of a subset of indices from the CVLT-II.

The emergence of age-related changes in recognition memory in healthy middle-aged adults using the CVLT-II.

Although age-related memory differences between young and older adults have been well documented, fewer studies have investigated memory changes in middle age. We examined the performance of healthy middle-aged adults (40-55 years of age; n = 32) in relation to healthy young (18-25 years of age; n = 57) and older adults (65+ years of age; n = 55) on variations of recognition discriminability (RD) indices derived from the California Verbal Learning Test-Second Edition (CVLT-II). Middle-aged adults performed significantly worse (ps < .05) than young adults on multiple RD indices that incorporate semantically related distractor items, suggesting memory changes in middle age may be associated with increased susceptibility to semantic interference. Moreover, middle-aged adults performed comparably to older adults across all RD indices, indicating the recognition profile of middle-aged adults on RD indices more closely resembles that of older adults than young adults.

Recall and Recognition Discriminability in Parkinson's Disease and Huntington's Disease.

BACKGROUND: Parkinson's disease (PD) and Huntington's disease (HD) are two neurodegenerative diseases affecting frontal-striatal function and memory ability. Studies using the original California Verbal Learning Test (CVLT) to examine recall and recognition abilities between these groups have produced mixed findings. Some found that individuals with HD demonstrate worse recall and recognition than those with PD, whereas others reported comparable performance. OBJECTIVE: We utilized multiple indices of recall and recognition discriminability, provided by the second and third editions of the CVLT (CVLT-II and CVLT-3, respectively), that allow for a more thorough assessment of more nuanced aspects of verbal memory function. METHODS: We examined differences between individuals with PD (n = 72) and those with HD (n = 77) on CVLT-II indices of recall discriminability (immediate, short delay free and cued, long delay free and cued) and recognition discriminability (total, source, semantic, and novel) using standardized scores while controlling for education and Dementia Rating Scale-2 scores. RESULTS: The HD group performed significantly worse than the PD group on all measures of recall and recognition discriminability (ps < 0.05), and group differences were associated with large Cohen's d effect sizes. CONCLUSIONS: Our findings suggest that individuals with HD are more impaired than individuals with PD in more nuanced aspects of recall and recognition memory function. These CVLT indices yield more thorough assessments of recall and recognition memory function and have the potential to improve efforts to characterize and distinguish profiles of memory loss in different neurodegenerative populations, including PD and HD.

New Intrusion Analyses on the CVLT-3: Utility in Distinguishing the Memory Disorders of Alzheimer's versus Huntington's Disease.

OBJECTIVES: Research has shown that analyzing intrusion errors generated on verbal learning and memory measures is helpful for distinguishing between the memory disorders associated with Alzheimer's disease (AD) and other neurological disorders, including Huntington's disease (HD). Moreover, preliminary evidence suggests that certain clinical populations may be prone to exhibit different types of intrusion errors. METHODS: We examined the prevalence of two new California Verbal Learning Test-3 (CVLT-3) intrusion subtypes - across-trial novel intrusions and across/within trial repeated intrusions - in individuals with AD or HD. We hypothesized that the encoding/storage impairment associated with medial-temporal involvement in AD would result in a greater number of novel intrusions on the delayed recall trials of the CVLT-3, whereas the executive dysfunction associated with subcortical-frontal involvement in HD would result in a greater number of repeated intrusions across trials. RESULTS: The AD group generated significantly more across-trial novel intrusions than across/within trial repeated intrusions on the delayed cued-recall trials, whereas the HD group showed the opposite pattern on the delayed free-recall trials. CONCLUSIONS: These new intrusion subtypes, combined with traditional memory analyses (e.g., recall versus recognition performance), promise to enhance our ability to distinguish between the memory disorders associated with primarily medial-temporal versus subcortical-frontal involvement.

Spatial memory ability during middle age may depend on level of spatial similarity.

Spatial memory impairment is well documented in old age; however, less is known about spatial memory during middle age. We examined the performance of healthy young, middle-aged, and older adults on a spatial memory task with varying levels of spatial similarity (distance). On low similarity trials, young adults significantly outperformed middle-aged adults, who significantly outperformed older adults (Ps < 0.05). On high similarity trials, young adults significantly outperformed middle-aged and older adults (Ps < 0.05); however, middle-aged and older adults did not differ. Subtle age-related changes in spatial memory may emerge during middle age, particularly when spatial similarity is high.

New Yes/No Recognition Memory Analysis on the California Verbal Learning Test-3: Clinical Utility in Alzheimer's and Huntington's Disease.

OBJECTIVES: The third edition of the California Verbal Learning Test (CVLT-3) includes a new index termed List A versus Novel/Unrelated recognition discriminability (RD) on the Yes/No Recognition trial. Whereas the Total RD index incorporates false positive (FP) errors associated with all distractors (including List B and semantically related items), the new List A versus Novel/Unrelated RD index incorporates only FP errors associated with novel, semantically unrelated distractors. Thus, in minimizing levels of source and semantic interference, the List A versus Novel/Unrelated RD index may yield purer assessments of yes/no recognition memory independent of vulnerability to source memory difficulties or semantic confusion, both of which are often seen in individuals with primarily frontal-system dysfunction (e.g., early Huntington's disease [HD]). METHODS: We compared the performance of individuals with Alzheimer's disease (AD) and HD in mild and moderate stages of dementia on CVLT-3 indices of Total RD and List A versus Novel/Unrelated RD. RESULTS: Although AD and HD subgroups exhibited deficits on both RD indices relative to healthy comparison groups, those with HD generally outperformed those with AD, and group differences were more robust on List A versus Novel/Unrelated RD than on Total RD. CONCLUSIONS: Our findings highlight the clinical utility of the new CVLT-3 List A versus Novel/Unrelated RD index, which (a) maximally assesses yes/no recognition memory independent of source and semantic interference; and (b) provides a greater differentiation between individuals whose memory disorder is primarily at the encoding/storage level (e.g., as in AD) versus at the retrieval level (e.g., as in early HD). (JINS, 2018, 24, 833-841).