Introduction: We investigated the feasibility and validity of the remotely-administered neuropsychological battery from the National Alzheimer's Coordinating Center Uniform Data Set (UDS T-Cog).
Methods: Two hundred twenty Penn Alzheimer's Disease Research Center participants with unimpaired cognition, mild cognitive impairment, and dementia completed the T-Cog during their annual UDS evaluation. We assessed administration feasibility and diagnostic group differences cross-sectionally across telephone versus videoconference modalities, and compared T-Cog to prior in-person UDS scores longitudinally.
Functional magnetic resonance imaging (fMRI) offers an alternative to the traditional Wada test for presurgical language and memory lateralization that carries almost no risk. However, fMRI lateralization of episodic memory remains challenging because the hippocampus, which is fundamental to episodic memory, is smaller, more prone to susceptibility artifact, and harder to functionally modulate than language regions. We previously showed that a complex scene memory task can lateralize memory function in the mesial temporal lobe.
View Article and Find Full Text PDFBackground: Volumetry of subregions in the medial temporal lobe (MTL) computed from automatic segmentation in MRI can track neurodegeneration in Alzheimer's disease. However, image quality may vary in MRI. Poor quality MR images can lead to unreliable segmentation of MTL subregions.
View Article and Find Full Text PDFIntroduction: We investigate pathological correlates of plasma phosphorylated tau 181 (p-tau), glial fibrillary acidic protein (GFAP), and neurofilament light chain (NfL) across a clinically diverse spectrum of neurodegenerative disease, including normal cognition (NormCog) and impaired cognition (ImpCog).
Methods: Participants were NormCog (n = 132) and ImpCog (n = 461), with confirmed β-amyloid (Aβ+/-) status (cerebrospinal fluid, positron emission tomography, autopsy) and single molecule array plasma measurements. Logistic regression and receiver operating characteristic (ROC) area under the curve (AUC) tested how combining plasma analytes discriminated Aβ+ from Aβ-.
Introduction: Individuals in socioeconomically disadvantaged neighborhoods exhibit increased risk for impaired cognitive function. Whether this association relates to the major dementia-related neuropathologies is unknown.
Methods: This cross-sectional study included 469 autopsy cases from 2011 to 2023.
Alzheimer Dis Assoc Disord
February 2024
Objective: We developed the Technology in Caring Questionnaire (TCQ) to assess the use of technology-based strategies by dementia caregivers.
Methods: One hundred caregivers completed a survey that included TCQ items along with measures of technology proficiency and patient and caregiver-centered outcomes.
Results: The final 34-item TCQ scale had adequate to excellent internal consistency (raw Cronbach alpha = 0.
We used indirect brain mapping with virtual lesion tractography to test the hypothesis that the extent of white matter tract disconnection due to white matter hyperintensities (WMH) is associated with corresponding tract-specific cognitive performance decrements. To estimate tract disconnection, WMH masks were extracted from FLAIR MRI data of 481 cognitively intact participants in the Alzheimer's Disease Neuroimaging Initiative (ADNI) and used as regions of avoidance for fiber tracking in diffusion MRI data from 50 healthy young participants from the Human Connectome Project. Estimated tract disconnection in the right inferior fronto-occipital fasciculus, right frontal aslant tract, and right superior longitudinal fasciculus mediated the effects of WMH volume on executive function.
View Article and Find Full Text PDFObjective: We examined how cognitive complaint types (CCTs) correlate with cognitive testing, perceived stress, and symptom distress in older adults with normal cognition and dementia.
Methods: Older adults (n = 259) with normal cognition, mild cognitive impairment, or mild-stage Alzheimer disease completed cognitive testing and self-report measures (Cognitive Difficulties Scale, Global Distress Index, Perceived Stress Scale). Cross-sectional analyses examined: (1) CCT composition by classification method,( 2) CCTs by diagnostic group, (3) correlations of CCTs with cognitive testing scores, and (4) correlations of CCTs with perceived stress and symptom distress.
Objective: Biomarkers of Alzheimer disease vary between groups of self-identified Black and White individuals in some studies. This study examined whether the relationships between biomarkers or between biomarkers and cognitive measures varied by racialized groups.
Methods: Cerebrospinal fluid (CSF), amyloid positron emission tomography (PET), and magnetic resonance imaging measures were harmonized across four studies of memory and aging.
Objective: Quantitative olfactory assessment has demonstrated clinical utility for the evaluation of a range of neurologic, psychiatric, and sinonasal conditions. Here, we provide age, sex, race, and education-specific normative data for the 12-item Sniffin Sticks Odor Identification Test (SSOIT-12) in older Black and White U.S.
View Article and Find Full Text PDFObjective: Personality change in Alzheimer's disease and related dementias (ADRD) is complicated by the patient and informant factors that confound accurate reporting of personality traits. We assessed the impact of caregiver burden on informant report of Big Five personality traits (extraversion, agreeableness, conscientiousness, neuroticism, and openness) and investigated the regional cortical volumes associated with larger discrepancies in the patient and informant report of the Big Five personality traits.
Method: Sixty-four ADRD participants with heterogeneous neurodegenerative clinical phenotypes and their informants completed the Big Five Inventory (BFI).
This study aims to design and pilot an empirically based mobile application () to increase daily activity in persons with apathy and ADRD and test its feasibility and preliminary efficacy. was developed to address impairments in goal-directed behaviour, including difficulty with initiation, planning, and motivation that contribute to apathy. Participants included patients with apathy and MCI, mild bvFTD, or mild AD and their caregivers.
View Article and Find Full Text PDFBackground: Assessment of personality change in Alzheimer's disease and related dementias (ADRD) is clinically meaningful but complicated by patient (i.e., reduced insight) and informant (i.
View Article and Find Full Text PDFActa Neuropathol
December 2022
Alzheimer's disease (AD) has multiple clinically and pathologically defined subtypes where the underlying causes of such heterogeneity are not well established. Rare TREM2 variants confer significantly increased risk for clinical AD in addition to other neurodegenerative disease clinical phenotypes. Whether TREM2 variants are associated with atypical clinical or pathologically defined subtypes of AD is not known.
View Article and Find Full Text PDFBackground: Episodic memory decline is a hallmark of Alzheimer's disease (AD). Subjective memory complaints (SMCs) may represent one of the earliest signs of impending cognitive decline. The degree to which self- or partner-reported SMCs predict cognitive change remains unclear.
View Article and Find Full Text PDFAlzheimer's disease neuropathologic change (ADNC) is clinically heterogenous and can present with a classic multidomain amnestic syndrome or focal non-amnestic syndromes. Here, we investigated the distribution and burden of phosphorylated and C-terminally cleaved tau pathologies across hippocampal subfields and cortical regions among phenotypic variants of Alzheimer's disease (AD). In this study, autopsy-confirmed patients with ADNC, were classified into amnestic (aAD, N = 40) and non-amnestic (naAD, N = 39) groups based on clinical criteria.
View Article and Find Full Text PDFIntroduction: Research addressing Alzheimer disease and related dementias must examine nonbiological factors influencing the risk for and expression of Alzheimer disease and related dementias. These factors address the interplay of cognition with lived experiences and social and structural determinants of health (SSDOH). However, coordinated measures of SSDOH are limited.
View Article and Find Full Text PDFStructural and social determinants of health (SSDoH) are environmental conditions in which individuals are born, live, learn, work, play, worship, and age that affect health, functioning, and quality-of-life outcomes across the life course. Growing evidence suggests that SSDoH can help to explain heterogeneity in outcomes in Alzheimer's disease and Alzheimer's disease and related dementias (AD/ADRD) research and clinical practice. The National Institute on Aging has prioritized collecting SSDoH data to elucidate disease mechanisms and aid discovery of disease-modifying treatments.
View Article and Find Full Text PDFBackground: Actuarial and statistical methods have been proposed as alternatives to conventional methods of diagnosing mild cognitive impairment (MCI), with the aim of enhancing diagnostic and prognostic validity, but have not been compared in racially diverse samples.
Objective: We compared the agreement of consensus, actuarial, and statistical MCI diagnostic methods, and their relationship to race and prognostic indicators, among diverse older adults.
Methods: Participants (N = 354; M age = 71; 68% White, 29% Black) were diagnosed with MCI or normal cognition (NC) according to clinical consensus, actuarial neuropsychological criteria (Jak/Bondi), and latent class analysis (LCA).
Objective: To determine whether patients with Lewy body dementia (LBD) with likely Alzheimer disease (AD)-type copathology are more impaired on confrontation naming than those without likely AD-type copathology.
Methods: We selected 57 patients with LBD (dementia with Lewy bodies [DLB], n = 38; Parkinson disease dementia [PDD], n = 19) with available AD CSF biomarkers and neuropsychological data. CSF β-amyloid (Aβ), phosphorylated-tau (p-tau), and total-tau (t-tau) concentrations were measured.
When facing decisions involving trade-offs between smaller, sooner and larger, delayed rewards, people tend to discount the value of future rewards. There are substantial individual differences in this tendency toward temporal discounting, however. One neurocognitive system that may underlie these individual differences is episodic memory, given the overlap in the neural circuitry involved in imagining the future and remembering the past.
View Article and Find Full Text PDFOlfactory dysfunction in epilepsy is well-documented in several olfactory domains. However, the clinical specificity of these deficits remains unknown. The aim of this systematic meta-analysis was to determine which domains of olfactory ability were most impaired in individuals with epilepsy, and to assess moderating factors affecting olfactory ability.
View Article and Find Full Text PDFThe objective of this cross-sectional study was to determine the extent and nature of self-reported musical abilities in persons with mild cognitive impairment (MCI). We recruited 60 older adults with a diagnosis of MCI from the Alzheimer's disease Core Center. We evaluated self-reported musical abilities using the Goldsmiths General Musical Sophistication Index.
View Article and Find Full Text PDFUnitization, that is, the encoding of an association as one integrated entity, has been shown to improve associative memory in populations presenting with associative memory deficit due to hippocampal dysfunction, such as amnesic patients with focal hippocampal lesions and healthy older adults. One reason for this benefit is that encoding of unitized associations would rely on the perirhinal cortex (PrC) and thus minimize the need for hippocampal recruitment. Mild cognitive impairment (MCI) is accompanied by a deficit in associative memory.
View Article and Find Full Text PDFBackground: Fine motor impairments are common in neurodegenerative disorders, yet standardized, quantitative measurements of motor abilities are uncommonly used in neurological practice. Thus, understanding and comparing fine motor abilities across disorders have been limited.
Objectives: The current study compared differences in finger tapping, inter-tap interval, and variability in Alzheimer's disease (AD), Parkinson's disease (PD), mild cognitive impairment (MCI), and healthy older adults (HOA).