Objective: With the increased use of computer-based tests in clinical and research settings, assessing retest reliability and reliable change of NIH Toolbox-Cognition Battery (NIHTB-CB) and Cogstate Brief Battery (Cogstate) is essential. Previous studies used mostly White samples, but Black/African Americans (B/AAs) must be included in this research to ensure reliability.
Method: Participants were B/AA consensus-confirmed healthy controls (HCs) (n = 49) or mild cognitive impairment (MCI) (n = 34) adults 60-85 years that completed NIHTB-CB and Cogstate for laptop at two timepoints within 4 months.
Introduction: A recently developed mild behavioral impairment (MBI) diagnostic framework standardizes the early characterization of neuropsychiatric symptoms in older adults. However, the joint contributions of Alzheimer's disease (AD) pathology and brain function to MBI remain unclear.
Methods: We test a novel model assessing direct relationships between AD biomarker status and MBI symptoms, as well as mediated effects through segregation of the salience and default-mode networks, using data from 128 participants with diagnosis of amnestic mild cognitive impairment or mild dementia-AD type.
Objectives: Identify which NIH Toolbox Cognition Battery (NIHTB-CB) subtest(s) best differentiate healthy controls (HC) from those with amnestic mild cognitive impairment (aMCI) and compare the discriminant accuracy between a model using a priori "Norm Adjusted" scores versus "Unadjusted" standard scores with age, sex, race/ethnicity, and education controlled for within the model. Racial differences were also examined.
Methods: Participants were Black/African American (B/AA) and White consensus-confirmed (HC = 96; aMCI = 62) adults 60-85 years old that completed the NIHTB-CB for tablet.
Objective: Repeated spaced sessions of repetitive transcranial magnetic stimulation (TMS) to the human primary motor cortex can lead to dose-dependent increases in motor cortical excitability. However, this has yet to be demonstrated in a defined cortical circuit. We aimed to examine the effects of repeated spaced cortical paired associative stimulation (cPAS) on excitability in the motor cortex.
View Article and Find Full Text PDFIntroduction: A recently developed mild behavioral impairment (MBI) diagnostic framework standardizes the early characterization of neuropsychiatric symptoms in older adults. However, the links between MBI, brain function, and Alzheimer's disease (AD) biomarkers are unclear.
Methods: Using data from 128 participants with diagnosis of amnestic mild cognitive impairment and mild dementia - Alzheimer's type, we test a novel model assessing direct relationships between AD biomarker status and MBI symptoms, as well as mediated effects through segregation of the salience and default-mode networks.
Only a third of individuals with mild cognitive impairment (MCI) progress to dementia of the Alzheimer's type (DAT). Identifying biomarkers that distinguish individuals with MCI who will progress to DAT (MCI-Converters) from those who will not (MCI-Non-Converters) remains a key challenge in the field. In our study, we evaluate whether the individual rates of loss of volumes of the Hippocampus and entorhinal cortex (EC) with age in the MCI stage can predict progression to DAT.
View Article and Find Full Text PDFAlzheimer's disease and related dementias (ADRD) present significant challenges including cognitive and functional loss, behavioral disruption, emotional distress, and significant financial burden. These stressors are amplified in minority groups, who experience higher rates of ADRD but less frequent and later diagnosis. There is therefore a critical need to identify tangible approaches to culturally informed dementia assessment and care for patients from diverse communities.
View Article and Find Full Text PDFBackground: Social engagement has beneficial effects during cognitive aging. Large-scale cognitive brain network functions are implicated in both social behaviors and cognition.
Objective: We evaluated associations between functional connectivity (FC) of large-scale brain cognitive networks and social engagement, characterized by self-reported social network size and contact frequency.
We sought to determine whether the biomarkers of chronic inflammation predict cognitive decline in a prospective observational study. We measured baseline serum soluble urokinase plasminogen activator receptor (suPAR) and high sensitivity C-reactive protein (hs-CRP) levels in 282 participants of the University of Michigan Memory and Aging Project. Cognitive function was measured using the Montreal Cognitive Assessment (MoCA) and the Clinical Dementia Rating (CDR) scale for up to five time points.
View Article and Find Full Text PDFLogopenic variant primary progressive aphasia (lvPPA) is characterized by word-finding deficits and phonologic errors in fluent speech. Transcranial direct current stimulation (tDCS) targeting either left temporoparietal junction (TPJ) or left inferior frontal gyrus (IFG) show evidence of improving language function in lvPPA. The present case study evaluated the effects of two separate rounds of high definition tDCS (HD-tDCS) (4 mA; 30 sessions) on language and functional neuroimaging in a 57-year-old woman with lvPPA.
View Article and Find Full Text PDFMost individuals with Parkinson's disease experience cognitive decline. Mounting evidence suggests this is partially caused by cholinergic denervation due to α-synuclein pathology in the cholinergic basal forebrain. Alpha-synuclein deposition causes inflammation, which can be measured with free water fraction, a diffusion MRI-derived metric of extracellular water.
View Article and Find Full Text PDFBackground And Objectives: Social isolation is a risk factor for cognitive decline and dementia. We conducted a randomized controlled clinical trial (RCT) of enhanced social interactions, hypothesizing that conversational interactions can stimulate brain functions among socially isolated older adults without dementia. We report topline results of this multisite RCT (Internet-based conversational engagement clinical trial [I-CONECT]; NCT02871921).
View Article and Find Full Text PDFPurpose: Alzheimer disease (AD) biomarker testing is now common in research and approaching clinical translation. Disclosure protocols must be informed by diverse participants' perspectives on if/how the information would be useful.
Methods: This study utilized semistructured interviews assessing interest in receiving positron emission tomography (PET) amyloid and tau results, as well as perceived risks and benefits of hypothetical PET disclosure as a function of race and participant diagnosis.
Transcranial alternating current stimulation (tACS) is a form of noninvasive brain stimulation that has experienced rapid growth within the aging population over the past decade due to its potential for modulating cognitive functioning across the "intact" to dementia spectrum. For this reason, we performed a systematic review of the literature to evaluate the efficacy of tACS on cognitive functioning in older adults, including those with cognitive impairment. Our review was completed in June 2023 using Psych INFO, Embase, PubMed, and Cochrane databases.
View Article and Find Full Text PDFBackground: Early detection is necessary for the treatment of dementia. Computerized testing has become more widely used in clinical trials; however, it is unclear how sensitive these measures are to early signs of neurodegeneration. We investigated the use of the NIH Toolbox-Cognition (NIHTB-CB) and Cogstate-Brief computerized neuropsychological batteries in the identification of mild cognitive impairment (MCI) versus healthy older adults [healthy control (HC)] and amnestic (aMCI) versus nonamnestic MCI (naMCI).
View Article and Find Full Text PDFBackground: Few studies have investigated tolerability, blinding, and double-blinding of High-Definition transcranial Direct Current Stimulation (HD-tDCS) at amplitudes above 2 milliamps (mA).
Objective: We examined a) tolerability of HD-tDCS during stimulation sessions and b) blinding and double blinding of participants and study team members.
Methods: Data from a mixed neurologic sample of 292 older adults were pooled from 3046 HD-tDCS sessions (2329 active; 717 sham).
Background: Purposeful social interactions are important for healthy aging. We conducted a pilot trial of SPEAK! (Seniors Promoting English Acquisition and Knowledge), an intervention providing older volunteers with a safe, accessible opportunity to converse via webcam with English-language learners.
Methods: A neurologically mixed sample of older adults was randomized to 8 weekly, webcam conversations with English-language learners or a waitlist control.
Objective: Few studies have evaluated in-home teleneuropsychological (teleNP) assessment and none, to our knowledge, has evaluated the National Alzheimer's Coordinating Center's (NACC) Uniform Data Set version 3 tele-adapted test battery (UDS v3.0 t-cog). The current study evaluates the reliability of the in-home UDS v3.
View Article and Find Full Text PDFCognitive screening instruments (CSI) have variable sensitivity and specificity to the cognitive changes associated with dementia syndromes, and the most recent systematic review found insufficient evidence to support the benefit of cognitive screening tools in older adults residing within the community. Consequently, there is a critical need to improve CSI methods, which have not yet incorporated advances in psychometrics, neuroscience, and technology. The primary goal of this article is to provide a framework for transitioning from legacy CSIs to advanced dementia screening measurement.
View Article and Find Full Text PDFBiol Psychiatry Cogn Neurosci Neuroimaging
February 2023
Background: Treatments for cognitive dysfunction in neuropsychiatric conditions are urgently needed. Cognitive training and transcranial direct current stimulation (tDCS) hold promise, and there is growing interest in combined or multimodal treatments, though studies to date have had small samples and inconsistent results.
Methods: A systematic review and meta-analysis was completed.
Purpose –: The purpose of this paper is to examine the reliability and validity of the Abbreviated Mental Test (AMT) and the agreement with the Mini-Mental State Examination (MMSE).
Design/methodology/approach –: This cross-sectional study included 446 older adults who were recruited by cluster sampling from 200,481 adults aged more than 60 years. For each participant, the AMT was administered by village health volunteers and, on a separate day, by a trained professional who also administered the MMSE.
Standardized tests of learning and memory are sensitive to changes associated with both aging and superimposed neurodegenerative diseases. Unfortunately, repeated behavioral test administration can be confounded by practice effects (PE), which may obscure declines in level of abilities and contribute to misdiagnoses. Growing evidence, however, suggests PE over successive longitudinal measurements may differentially predict cognitive status and risk for progressive decline associated with aging, mild cognitive impairment (MCI), and dementia.
View Article and Find Full Text PDFIntroduction: Dual tasking impairments are an increasingly recognized contributor to falls in Parkinson disease (PD) and may be a promising therapeutic target for PD fall prevention trials. Depending on the context, ambulatory dual tasking difficulties may be caused by different types of neurocognitive impairments.
Methods: We performed a cross-sectional analysis of 21 participants with PD.