542 results on '"Libon, David J."'
Search Results
2. Explainable semi-supervised deep learning shows that dementia is associated with small, avocado-shaped clocks with irregularly placed hands
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Bandyopadhyay, Sabyasachi, Wittmayer, Jack, Libon, David J., Tighe, Patrick, Price, Catherine, and Rashidi, Parisa
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- 2023
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3. Latent Profile Analysis of Cognition in a Non-Demented Diverse Cohort: A Focus on Modifiable Cardiovascular and Lifestyle Factors.
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Lamar, Melissa, Drabick, Deborah, Boots, Elizabeth A, Agarwal, Puja, Emrani, Sheina, Delano-Wood, Lisa, Bondi, Mark W, Barnes, Lisa L, and Libon, David J
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Clinical Research ,Neurosciences ,Basic Behavioral and Social Science ,Nutrition ,Behavioral and Social Science ,Cardiovascular ,Aging ,Prevention ,Neurodegenerative ,Good Health and Well Being ,Black or African American ,Aged ,Cognition ,Diet ,Mediterranean ,Exercise ,Female ,Heart Disease Risk Factors ,Hispanic or Latino ,Humans ,Life Style ,Male ,Models ,Statistical ,Neuropsychological Tests ,White People ,cognition ,diversity ,latent profile analysis ,lifestyle ,Mediterranean diet ,Clinical Sciences ,Cognitive Sciences ,Neurology & Neurosurgery - Abstract
BackgroundCognitively-defined subgroups are well-documented within neurodegeneration.ObjectiveWe examined such profiles in diverse non-demented older adults and considered how resulting subgroups relate to modifiable factors associated with neurodegeneration.Methods121 non-demented (MMSE = 28.62) diverse (46%non-Latino Black, 40%non-Latino White, 15%Latino) community-dwelling adults (age = 67.7 years) completed cognitive, cardiovascular, physical activity, and diet evaluations. Latent profile analyses (LPA) employed six cognitive scores (letter fluency, letter-number sequencing, confrontational naming, 'animal' fluency, list-learning delayed recall, and recognition discriminability) to characterize cognitively-defined subgroups. Differences between resulting subgroups on cardiovascular (composite scores of overall health; specific health components including fasting blood levels) and lifestyle (sedentary behavior; moderate-to-vigorous physical activity; Mediterranean diet consumption) factors were examined using ANCOVAs adjusting for relevant confounders.ResultsBased on sample means across cognitive scores, LPA resulted in the following cognitive subgroups: 1) high-average cognition, 55%non-Latino White and 64%female participants; 2) average cognition, 58%non-Latino Black and 68%male participants; 3) lower memory, 58%non-Latino Black participants; and 4) lower executive functioning, 70%Latinos. The high-average subgroup reported significantly higher Mediterranean diet consumption than the average subgroup (p = 0.001). The lower executive functioning group had higher fasting glucose and hemoglobin A1c than all other subgroups (p-values
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- 2021
4. Variational autoencoder provides proof of concept that compressing CDT to extremely low-dimensional space retains its ability of distinguishing dementia
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Bandyopadhyay, Sabyasachi, Dion, Catherine, Libon, David J., Price, Catherine, Tighe, Patrick, and Rashidi, Parisa
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- 2022
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5. Word-List Intrusion Errors Predict Progression to Mild Cognitive Impairment
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Thomas, Kelsey R, Eppig, Joel, Edmonds, Emily C, Jacobs, Diane M, Libon, David J, Au, Rhoda, Salmon, David P, Bondi, Mark W, and Initiative*, The Alzheimer’s Disease Neuroimaging
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Clinical and Health Psychology ,Psychology ,Neurodegenerative ,Aging ,Dementia ,Acquired Cognitive Impairment ,Behavioral and Social Science ,Neurosciences ,Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD) ,Brain Disorders ,Alzheimer's Disease ,Detection ,screening and diagnosis ,4.1 Discovery and preclinical testing of markers and technologies ,Neurological ,Aged ,Aged ,80 and over ,Apolipoproteins E ,Biomarkers ,Cognitive Dysfunction ,Disease Progression ,Female ,Humans ,Male ,Memory ,Middle Aged ,Mood Disorders ,Neuropsychological Tests ,Predictive Value of Tests ,Psychomotor Performance ,Verbal Learning ,process scores ,intrusion errors ,preclinical Alzheimer's disease ,mild cognitive impairment ,subtle cognitive decline ,Alzheimer’s Disease Neuroimaging Initiative* ,Cognitive Sciences ,Experimental Psychology ,Biological psychology ,Cognitive and computational psychology - Abstract
ObjectivePreclinical Alzheimer's disease (AD) defined by a positive AD biomarker in the presence of normal cognition is presumed to precede mild cognitive impairment (MCI). Subtle cognitive deficits and cognitive inefficiencies in preclinical AD may be detected through process and error scores on neuropsychological tests in those at risk for progression to MCI.MethodCognitively normal participants (n = 525) from the Alzheimer's Disease Neuroimaging Initiative were followed for up to 5 years and classified as either stable normal (n = 305) or progressed to MCI (n = 220). Cox regressions were used to determine whether baseline process scores on the Rey Auditory Verbal Learning Test (AVLT; intrusion errors, learning slope, proactive interference, retroactive interference) predicted progression to MCI and a Clinical Dementia Rating (CDR) score of 1 after considering demographic characteristics, apolipoprotein E ε4 status, cerebrospinal fluid AD biomarkers, ischemia risk, mood, functional difficulty, and standard neuropsychological total test scores for the model.ResultsBaseline AVLT intrusion errors predicted progression to MCI (hazard ratio = 1.04, 95% confidence interval 1.01-1.07, p = .008) and improved model fit after the other valuable predictors were already in the model, χ2(df = 1) = 6.330, p = .012. AVLT intrusion errors also predicted progression to CDR = 1 (hazard ratio = 1.10, 95% confidence interval 1.02-1.18, p = .016) and again improved model fit, χ2(df = 1) = 4.682, p = .030.ConclusionsIntrusion errors on the AVLT contribute unique value for predicting progression from normal cognition to MCI and normal cognition to mild dementia (CDR = 1). Intrusion errors appear to reflect subtle change and inefficiencies in cognition that precede impairment detected by neuropsychological total scores. (PsycINFO Database Record
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- 2018
6. Baseline White Matter Hyperintensities and Hippocampal Volume are Associated With Conversion From Normal Cognition to Mild Cognitive Impairment in the Framingham Offspring Study
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Bangen, Katherine J, Preis, Sarah R, Delano-Wood, Lisa, Wolf, Philip A, Libon, David J, Bondi, Mark W, Au, Rhoda, DeCarli, Charles, and Brickman, Adam M
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Biological Psychology ,Psychology ,Neurodegenerative ,Acquired Cognitive Impairment ,Alzheimer's Disease ,Brain Disorders ,Dementia ,Aging ,Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD) ,Clinical Research ,Neurosciences ,Behavioral and Social Science ,Neurological ,Aged ,Cognition ,Cognitive Dysfunction ,Cross-Sectional Studies ,Female ,Hippocampus ,Humans ,Longitudinal Studies ,Magnetic Resonance Imaging ,Male ,Massachusetts ,Neuropsychological Tests ,Prospective Studies ,White Matter ,mild cognitive impairment ,MCI ,MRI ,volumetric MRI ,white matter hyperintensity ,hippocampal volume ,Clinical Sciences ,Cognitive Sciences ,Geriatrics ,Clinical sciences ,Biological psychology - Abstract
IntroductionWe examined associations between magnetic resonance imaging (MRI) markers of cerebrovascular disease and neurodegeneration with mild cognitive impairment (MCI) diagnosis at baseline and conversion from normal cognition to MCI at follow-up.MethodsFramingham Offspring participants underwent brain MRI and neuropsychological assessment at baseline (n=1049) and follow-up (n=561). Participants were classified at baseline and at follow-up as cognitively normal or MCI using sensitive neuropsychological criteria. White matter hyperintensity (WMH) volume, covert brain infarcts, hippocampal volume, and total cerebral brain volume were quantified.ResultsBaseline measures of WMH and hippocampal volume were associated with MCI status cross-sectionally and also with conversion from normal cognition to MCI at 6.5-year follow-up. Annualized change rates in total cerebral brain volume and hippocampal volume were associated with conversion from normal cognition to MCI to follow-up.DiscussionBaseline WMH and hippocampal volume are markers that are both associated with conversion from normal cognition to MCI, highlighting the role of both vascular lesions and neurodegeneration in MCI.
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- 2018
7. Assessing Working Memory in Mild Cognitive Impairment with Serial Order Recall
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Emrani, Sheina, Libon, David J, Lamar, Melissa, Price, Catherine C, Jefferson, Angela L, Gifford, Katherine A, Hohman, Timothy J, Nation, Daniel A, Delano-Wood, Lisa, Jak, Amy, Bangen, Katherine J, Bondi, Mark W, Brickman, Adam M, Manly, Jennifer, Swenson, Rodney, Au, Rhoda, and Analysis, on behalf of the Consortium for Clinical and Epidemiological Neuropsychological Data
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Psychology ,Applied and Developmental Psychology ,Dementia ,Acquired Cognitive Impairment ,Clinical Trials and Supportive Activities ,Brain Disorders ,Clinical Research ,Aged ,Aged ,80 and over ,Cognitive Dysfunction ,Executive Function ,Female ,Humans ,Male ,Memory Disorders ,Memory ,Short-Term ,Mental Recall ,Neuropsychological Tests ,Regression Analysis ,Serial Learning ,Boston process approach ,digit span ,executive functions ,mild cognitive impairment ,serial order ,working memory ,Consortium for Clinical and Epidemiological Neuropsychological Data Analysis ,Clinical Sciences ,Neurosciences ,Cognitive Sciences ,Neurology & Neurosurgery ,Clinical sciences ,Biological psychology - Abstract
BackgroundWorking memory (WM) is often assessed with serial order tests such as repeating digits backward. In prior dementia research using the Backward Digit Span Test (BDT), only aggregate test performance was examined.ObjectiveThe current research tallied primacy/recency effects, out-of-sequence transposition errors, perseverations, and omissions to assess WM deficits in patients with mild cognitive impairment (MCI).MethodsMemory clinic patients (n = 66) were classified into three groups: single domain amnestic MCI (aMCI), combined mixed domain/dysexecutive MCI (mixed/dys MCI), and non-MCI where patients did not meet criteria for MCI. Serial order/WM ability was assessed by asking participants to repeat 7 trials of five digits backwards. Serial order position accuracy, transposition errors, perseverations, and omission errors were tallied.ResultsA 3 (group)×5 (serial position) repeated measures ANOVA yielded a significant group×trial interaction. Follow-up analyses found attenuation of the recency effect for mixed/dys MCI patients. Mixed/dys MCI patients scored lower than non-MCI patients for serial position 3 (p
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- 2018
8. Neuropsychological Criteria for Mild Cognitive Impairment in the Framingham Heart Study’s Old-Old
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Wong, Christina G, Thomas, Kelsey R, Edmonds, Emily C, Weigand, Alexandra J, Bangen, Katherine J, Eppig, Joel S, Jak, Amy J, Devine, Sherral A, Delano-Wood, Lisa, Libon, David J, Edland, Steven D, Au, Rhoda, and Bondi, Mark W
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Biomedical and Clinical Sciences ,Neurosciences ,Clinical Sciences ,Brain Disorders ,Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD) ,Dementia ,Neurodegenerative ,Acquired Cognitive Impairment ,Aging ,Behavioral and Social Science ,Alzheimer's Disease ,Aged ,Aged ,80 and over ,Cognitive Dysfunction ,Disease Progression ,Female ,Geriatric Assessment ,Humans ,Longitudinal Studies ,Male ,Neuropsychological Tests ,Predictive Value of Tests ,Proportional Hazards Models ,Reproducibility of Results ,Cognitive deficits ,Neuropsychology ,Diagnostic criteria ,Mild cognitive impairment ,Cognitive Sciences ,Geriatrics ,Clinical sciences - Abstract
Background/aimsMild cognitive impairment (MCI) lacks a "gold standard" operational definition. The Jak/Bondi actuarial neuropsychological criteria for MCI are associated with improved diagnostic stability and prediction of progression to dementia compared to conventional MCI diagnostic approaches, although its utility in diagnosing MCI in old-old individuals (age 75+) is unknown. Therefore, we investigated the applicability of neuropsychological MCI criteria among old-old from the Framingham Heart Study.MethodsA total of 347 adults (ages 79-102) were classified as cognitively normal or MCI via Jak/Bondi and conventional Petersen/Winblad criteria, which differ on cutoffs for cognitive impairment and number of impaired scores required for a diagnosis. Cox models examined MCI status in predicting risk of progression to dementia.ResultsMCI diagnosed by both the Jak/Bondi and Petersen/Winblad criteria was associated with incident dementia; however, when both criteria were included in the regression model together, only the Jak/Bondi criteria remained statistically significant. At follow-up, the Jak/Bondi criteria had a lower MCI-to-normal reversion rate than the Petersen/Winblad criteria.ConclusionsOur findings are consistent with previous research on the Jak/Bondi criteria and support the use of a comprehensive neuropsychological diagnostic approach for MCI among old-old individuals.
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- 2018
9. Right up- left down
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Heilman, Kenneth M., Libon, David J., Sun, Chichun E., and Price, Catherine C.
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- 2021
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10. Digital assessment of cognition in neurodegenerative disease: a data driven approach leveraging artificial intelligence.
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Libon, David J., Swenson, Rod, Price, Catherine C., Lamar, Melissa, Cosentino, Stephanie, Bezdicek, Ondrej, Kling, Mitchel A., Tobyne, Sean, Jannati, Ali, Banks, Russell, and Pascual-Leone, Alvaro
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ARTIFICIAL intelligence ,RECOLLECTION (Psychology) ,CONTROL (Psychology) ,EXECUTIVE function ,NEURODEGENERATION ,COGNITION - Abstract
Introduction: A rapid and reliable neuropsychological protocol is essential for the efficient assessment of neurocognitive constructs related to emergent neurodegenerative diseases. We developed an AI-assisted, digitally administered/scored neuropsychological protocol that can be remotely administered in -10min. This protocol assesses the requisite neurocognitive constructs associated with emergent neurodegenerative illnesses. Methods: The protocol was administered to 77 ambulatory care/memory clinic patients (56.40% women; 88.50% Caucasian). The protocol includes a 6-word version of the Philadelphia (repeatable) Verbal Learning Test [P(r)VLT], three trials of 5 digits backward fromthe Backwards Digit Span Test (BDST), and the "animal" fluency test. The protocol provides a comprehensive set of traditional "core" measures that are typically obtained through paper-and-pencil tests (i.e., serial list learning, immediate and delayed free recall, recognition hits, percent correct serial order backward digit span, and "animal" fluency output). Additionally, the protocol includes variables that quantify errors and detail the processes used in administering the tests. It also features two separate, norm-referenced summary scores specifically designed to measure executive control and memory. Results: Using four core measures, we used cluster analysis to classify participants into four groups: cognitively unimpaired (CU; n = 23), amnesticmild cognitive impairment (MCI; n = 17), dysexecutive MCI (n = 23), and dementia (n = 14). Subsequent analyses of error and process variables operationally defined key features of amnesia (i.e., rapid forgetting, extra-list intrusions, profligate responding to recognition foils); key features underlying reduced executive abilities (i.e., BDST items and dysexecutive errors); and the strength of the semantic association between successive responses on the "animal" fluency test. Executive and memory index scores effectively distinguished between all four groups. There was over 90% agreement between how cluster analysis of digitally obtained measures classified patients compared to classification using a traditional comprehensive neuropsychological protocol. The correlations between digitally obtained outcome variables and analogous paper/pencil measures were robust. Discussion: The digitally administered protocol demonstrated a capacity to identify patterns of impaired performance and classification similar to those observed with standard paper/pencil neuropsychological tests. The inclusion of both core measures and detailed error/process variables suggests that this protocol can detect subtle, nuanced signs of early emergent neurodegenerative illness efficiently and comprehensively. [ABSTRACT FROM AUTHOR]
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- 2024
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11. Common neurodegenerative disorders in the perioperative setting: Recommendations for screening from the Society for Perioperative Assessment and Quality Improvement (SPAQI)
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Wiggins, Margaret, Arias, Franchesca, Urman, Richard D., Richman, Deborah C., Sweitzer, Bobbie Jean, Edwards, Angela F., Armstrong, Melissa J., Chopra, Anita, Libon, David J., and Price, Catherine
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- 2020
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12. Rapid in-person cognitive screening in the preoperative setting: Test considerations and recommendations from the Society for Perioperative Assessment and Quality Improvement (SPAQI)
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Arias, Franchesca, Wiggins, Margaret, Urman, Richard D., Armstrong, Rebecca, Pfeifer, Kurt, Bader, Angela M., Libon, David J., Chopra, Anita, and Price, Catherine C.
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- 2020
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13. Interaction Between Midlife Blood Glucose and APOE Genotype Predicts Later Alzheimer’s Disease Pathology
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Bangen, Katherine J, Himali, Jayandra J, Beiser, Alexa S, Nation, Daniel A, Libon, David J, Fox, Caroline S, Seshadri, Sudha, Wolf, Philip A, McKee, Ann C, Au, Rhoda, and Delano-Wood, Lisa
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Dementia ,Alzheimer's Disease Related Dementias (ADRD) ,Brain Disorders ,Heart Disease ,Genetics ,Aging ,Cardiovascular ,Alzheimer's Disease ,Prevention ,Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD) ,Neurosciences ,Acquired Cognitive Impairment ,Neurodegenerative ,Aetiology ,2.1 Biological and endogenous factors ,Neurological ,Alzheimer Disease ,Apolipoprotein E4 ,Blood Glucose ,Brain ,Cohort Studies ,Female ,Genotype ,Humans ,Male ,Middle Aged ,Neurofibrillary Tangles ,Neuropsychological Tests ,Predictive Value of Tests ,Risk Factors ,Vascular Diseases ,Alzheimer's disease ,apolipoprotein E ,diabetes ,glucose ,neuropathology ,vascular risk ,Alzheimer’s disease ,Clinical Sciences ,Cognitive Sciences ,Neurology & Neurosurgery - Abstract
Elevated blood glucose and the apolipoprotein (APOE) ɛ4 allele have both been associated with increased dementia risk; however, the neuropathological mechanisms underlying these associations remain unclear. We examined the impact of APOE genotype and midlife blood glucose on post-mortem vascular and Alzheimer's disease (AD) neuropathology. Ninety-four participants from the Framingham Heart Study without diagnosed diabetes underwent health examination at midlife and brain autopsy at death. Histopathological measures of vascular and AD neuropathology were obtained and analyzed. Results demonstrated that, among APOE ɛ4 carriers, elevated blood glucose was associated with more severe AD pathology. There was no such relationship with vascular pathology. In a relatively healthy sample with low vascular risk burden, midlife elevated blood glucose was associated with greater AD pathology among APOE ɛ4 carriers. A better understanding of interactive effects of APOE genotype and vascular risk on neuropathology has implications for identification of individuals at risk for decline and long-term preventive treatment.
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- 2016
14. Pulse Pressure Is Associated With Early Brain Atrophy and Cognitive Decline
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Nation, Daniel A, Preis, Sarah R, Beiser, Alexa, Bangen, Katherine J, Delano-Wood, Lisa, Lamar, Melissa, Libon, David J, Seshadri, Sudha, Wolf, Philip A, and Au, Rhoda
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Biological Psychology ,Psychology ,Aging ,Stroke ,Cardiovascular ,Neurosciences ,Brain Disorders ,Acquired Cognitive Impairment ,Alzheimer's Disease ,Behavioral and Social Science ,Hypertension ,Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD) ,Neurodegenerative ,Dementia ,Clinical Research ,2.1 Biological and endogenous factors ,Aetiology ,Neurological ,Alleles ,Apolipoprotein E4 ,Atrophy ,Blood Pressure ,Brain ,Cognitive Dysfunction ,Cohort Studies ,Female ,Genotype ,Humans ,Magnetic Resonance Imaging ,Male ,Middle Aged ,Neuropsychological Tests ,Risk Factors ,pulse pressure ,cognition ,APOE ,Alzheimer disease ,Clinical Sciences ,Cognitive Sciences ,Geriatrics ,Clinical sciences ,Biological psychology - Abstract
We investigated whether midlife pulse pressure is associated with brain atrophy and cognitive decline, and whether the association was modified by apolipoprotein-E ε4 (APOE-ε4) and hypertension. Participants (549 stroke-free and dementia-free Framingham Offspring Cohort Study participants, age range=55.0 to 64.9 y) underwent baseline neuropsychological and magnetic resonance imaging (subset, n=454) evaluations with 5- to 7-year follow-up. Regression analyses investigated associations between baseline pulse pressure (systolic-diastolic pressure) and cognition, total cerebral volume and temporal horn ventricular volume (as an index of smaller hippocampal volume) at follow-up, and longitudinal change in these measures. Interactions with APOE-ε4 and hypertension were assessed. Covariates included age, sex, education, assessment interval, and interim stroke. In the total sample, baseline pulse pressure was associated with worse executive ability, lower total cerebral volume, and greater temporal horn ventricular volume 5 to 7 years later, and longitudinal decline in executive ability and increase in temporal horn ventricular volume. Among APOE-ε4 carriers only, baseline pulse pressure was associated with longitudinal decline in visuospatial organization. Findings indicate arterial stiffening, indexed by pulse pressure, may play a role in early cognitive decline and brain atrophy in mid to late life, particularly among APOE-ε4 carriers.
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- 2016
15. Cortical Amyloid Burden Differences Across Empirically-Derived Mild Cognitive Impairment Subtypes and Interaction with APOE ɛ4 Genotype
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Bangen, Katherine J, Clark, Alexandra L, Werhane, Madeline, Edmonds, Emily C, Nation, Daniel A, Evangelista, Nicole, Libon, David J, Bondi, Mark W, Delano-Wood, Lisa, and Initiative, for the Alzheimer’s Disease Neuroimaging
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Clinical and Health Psychology ,Psychology ,Biomedical Imaging ,Neurosciences ,Acquired Cognitive Impairment ,Clinical Research ,Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD) ,Dementia ,Aging ,Brain Disorders ,Alzheimer's Disease ,Neurodegenerative ,Neurological ,Aged ,Amyloid beta-Peptides ,Analysis of Variance ,Aniline Compounds ,Apolipoprotein E4 ,Cerebral Cortex ,Cluster Analysis ,Cognitive Dysfunction ,Ethylene Glycols ,False Positive Reactions ,Female ,Follow-Up Studies ,Genotype ,Humans ,Longitudinal Studies ,Male ,Positron-Emission Tomography ,Radiopharmaceuticals ,Amyloid ,apolipoprotein E ,APOE ,biomarkers ,florbetapir ,mild cognitive impairment ,neuroimaging ,neuropsychology ,PET ,positron emission tomography ,Alzheimer’s Disease Neuroimaging Initiative ,Clinical Sciences ,Cognitive Sciences ,Neurology & Neurosurgery ,Clinical sciences ,Biological psychology - Abstract
We examined cortical amyloid-β (Aβ) levels and interactions with apolipoprotein (APOE) ɛ4 genotype status across empirically-derived mild cognitive impairment (MCI) subgroups and cognitively normal older adults. Participants were 583 ADNI participants (444 MCI, 139 normal controls [NC]) with baseline florbetapir positron emission tomography (PET) amyloid imaging and neuropsychological testing. Of those with ADNI-defined MCI, a previous cluster analysis [1] classified 51% (n = 227) of the current sample as amnestic MCI, 8% (n = 37) as dysexecutive/mixed MCI, and 41% (n = 180) as cluster-derived normal (cognitively normal). Results demonstrated that the dysexecutive/mixed and amnestic MCI groups showed significantly greater levels of amyloid relative to the cluster-derived normal and NC groups who did not differ from each other. Additionally, 78% of the dysexecutive/mixed, 63% of the amnestic MCI, 42% of the cluster-derived normal, and 34% of the NC group exceeded the amyloid positivity threshold. Finally, a group by APOE genotype interaction demonstrated that APOE ɛ4 carriers within the amnestic MCI, cluster-derived normal, and NC groups showed significantly greater amyloid accumulation compared to non-carriers of their respective group. Such an interaction was not revealed within the dysexecutive/mixed MCI group which was characterized by both greater cognitive impairment and amyloid accumulation compared to the other participant groups. Our results from the ADNI cohort show considerable heterogeneity in Aβ across all groups studied, even within a group of robust NC participants. Findings suggest that conventional criteria for MCI may be susceptible to false positive diagnostic errors, and that onset of Aβ accumulation may occur earlier in APOE ɛ4 carriers compared to non-carriers.
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- 2016
16. Visuoconstructional Impairment in Subtypes of Mild Cognitive Impairment
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Ahmed, Samrah, Brennan, Laura, Eppig, Joel, Price, Catherine C, Lamar, Melissa, Delano-Wood, Lisa, Bangen, Katherine J, Edmonds, Emily C, Clark, Lindsey, Nation, Daniel A, Jak, Amy, Au, Rhoda, Swenson, Rodney, Bondi, Mark W, and Libon, David J
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Biological Psychology ,Clinical and Health Psychology ,Psychology ,Neurosciences ,Behavioral and Social Science ,Aging ,Neurodegenerative ,Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD) ,Brain Disorders ,Dementia ,Acquired Cognitive Impairment ,Basic Behavioral and Social Science ,Aged ,Amnesia ,Case-Control Studies ,Cognitive Dysfunction ,Executive Function ,Female ,Humans ,Male ,Neuropsychological Tests ,Boston process approach ,clock drawing ,cluster analysis ,executive control ,mild cognitive impairment ,visuoconstruction ,Cognitive Sciences ,Clinical Psychology ,Applied and developmental psychology ,Biological psychology ,Clinical and health psychology - Abstract
Clock Drawing Test performance was examined alongside other neuropsychological tests in mild cognitive impairment (MCI). We tested the hypothesis that clock-drawing errors are related to executive impairment. The current research examined 86 patients with MCI for whom, in prior research, cluster analysis was used to sort patients into dysexecutive (dMCI, n = 22), amnestic (aMCI, n = 13), and multidomain (mMCI, n = 51) subtypes. First, principal components analysis (PCA) and linear regression examined relations between clock-drawing errors and neuropsychological test performance independent of MCI subtype. Second, between-group differences were assessed with analysis of variance (ANOVA) where MCI subgroups were compared to normal controls (NC). PCA yielded a 3-group solution. Contrary to expectations, clock-drawing errors loaded with lower performance on naming/lexical retrieval, rather than with executive tests. Regression analyses found increasing clock-drawing errors to command were associated with worse performance only on naming/lexical retrieval tests. ANOVAs revealed no differences in clock-drawing errors between dMCI versus mMCI or aMCI versus NCs. Both the dMCI and mMCI groups generated more clock-drawing errors than the aMCI and NC groups in the command condition. In MCI, language-related skills contribute to clock-drawing impairment.
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- 2016
17. The oblique effect: The relationship between profiles of visuospatial preference, cognition, and brain connectomics in older adults
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Peven, Jamie C., Chen, Yurong, Guo, Lei, Zhan, Liang, Boots, Elizabeth A., Dion, Catherine, Libon, David J., Heilman, Kenneth M., and Lamar, Melissa
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- 2019
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18. Verbal Memory and Brain Aging
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Libon, David J, Preis, Sarah R, Beiser, Alexa S, Devine, Sherral, Seshadri, Sudha, Wolf, Philip A, DeCarli, Charles, and Au, Rhoda
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Biological Psychology ,Biomedical and Clinical Sciences ,Psychology ,Acquired Cognitive Impairment ,Clinical Research ,Dementia ,Alzheimer's Disease ,Neurodegenerative ,Biomedical Imaging ,Rare Diseases ,Brain Disorders ,Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD) ,Aging ,Neurosciences ,Neurological ,Aged ,Atrophy ,Brain ,Cognitive Dysfunction ,Cohort Studies ,Female ,Humans ,Logic ,Magnetic Resonance Imaging ,Male ,Massachusetts ,Memory Disorders ,Middle Aged ,Prodromal Symptoms ,Task Performance and Analysis ,Wechsler Scales ,Logical Memory ,declarative memory ,preclinical dementia ,Alzheimer's disease ,Boston process approach ,Alzheimer’s disease ,Clinical Sciences ,Geriatrics ,Clinical sciences ,Biological psychology - Abstract
ObjectiveAnalysis sought to determine whether Wechsler Memory Scale-Logical Memory (LM)-correct responses and errors were related to magnetic resonance imaging (MRI) brain volume measurements.MethodsThe LM immediate (LM-I) and LM delay (LM-D) free recall correct responses and related and unrelated errors were scored. Principal components analysis yielded a 3-factor solution: LM-I and LM-D correct responses, LM-I and LM-D-unrelated errors, and LM-I/-D-related errors. The MRI total cerebral brain volume, frontal brain volume, temporal horn volume (THV), and white matter hyperintensities volume (WMHIV) were obtained.ResultsIncreasing THV (suggesting greater regional atrophy) was associated with lower scores on the LM-correct responses factor. Extensive WMHIV was associated with higher scores on the LM-related errors factor.ConclusionThese results suggest that LM-correct responses could relate to emerging brain alterations. Longitudinal research might enhance the sensitivity of this test to identify preclinical impairment and persons at risk of mild cognitive impairment and dementia.
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- 2015
19. Susceptibility of the conventional criteria for mild cognitive impairment to false‐positive diagnostic errors
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Edmonds, Emily C, Delano‐Wood, Lisa, Clark, Lindsay R, Jak, Amy J, Nation, Daniel A, McDonald, Carrie R, Libon, David J, Au, Rhoda, Galasko, Douglas, Salmon, David P, Bondi, Mark W, and Initiative, Alzheimer's Disease Neuroimaging
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Biomedical and Clinical Sciences ,Biological Psychology ,Clinical Sciences ,Neurosciences ,Psychology ,Alzheimer's Disease ,Dementia ,Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD) ,Aging ,Acquired Cognitive Impairment ,Brain Disorders ,Neurodegenerative ,Clinical Research ,Neurological ,Aged ,Aged ,80 and over ,Amyloid beta-Peptides ,Apolipoprotein E4 ,Biomarkers ,Cluster Analysis ,Cognitive Dysfunction ,Databases ,Factual ,Diagnostic Errors ,Disease Progression ,Disease Susceptibility ,Female ,Humans ,Male ,Mental Status Schedule ,Middle Aged ,Neuropsychological Tests ,Peptide Fragments ,tau Proteins ,Mild cognitive impairment ,MCI ,Alzheimer's disease ,Neuropsychology ,Misdiagnosis ,Misclassification ,Cluster analysis ,Alzheimer's Disease Neuroimaging Initiative ,Geriatrics ,Clinical sciences ,Biological psychology - Abstract
BackgroundWe assessed whether mild cognitive impairment (MCI) subtypes could be empirically derived within the Alzheimer's Disease Neuroimaging Initiative (ADNI) MCI cohort and examined associated biomarkers and clinical outcomes.MethodsCluster analysis was performed on neuropsychological data from 825 MCI ADNI participants.ResultsFour subtypes emerged: (1) dysnomic (n = 153), (2) dysexecutive (n = 102), (3) amnestic (n = 288), and (4) cluster-derived normal (n = 282) who performed within normal limits on cognitive testing. The cluster-derived normal group had significantly fewer APOE ε4 carriers and fewer who progressed to dementia compared with the other subtypes; they also evidenced cerebrospinal fluid Alzheimer's disease biomarker profiles that did not differ from the normative reference group.ConclusionsIdentification of empirically derived MCI subtypes demonstrates heterogeneity in MCI cognitive profiles that is not captured by conventional criteria. The large cluster-derived normal group suggests that conventional diagnostic criteria are susceptible to false-positive errors, with the result that prior MCI studies may be diluting important biomarker relationships.
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- 2015
20. Association Between the Digital Clock Drawing Test and Neuropsychological Test Performance: Large Community-Based Prospective Cohort (Framingham Heart Study)
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Yuan, Jing, Libon, David J, Karjadi, Cody, Ang, Alvin F A, Devine, Sherral, Auerbach, Sanford H, Au, Rhoda, and Lin, Honghuang
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Computer applications to medicine. Medical informatics ,R858-859.7 ,Public aspects of medicine ,RA1-1270 - Abstract
BackgroundThe Clock Drawing Test (CDT) has been widely used in clinic for cognitive assessment. Recently, a digital Clock Drawing Text (dCDT) that is able to capture the entire sequence of clock drawing behaviors was introduced. While a variety of domain-specific features can be derived from the dCDT, it has not yet been evaluated in a large community-based population whether the features derived from the dCDT correlate with cognitive function. ObjectiveWe aimed to investigate the association between dCDT features and cognitive performance across multiple domains. MethodsParticipants from the Framingham Heart Study, a large community-based cohort with longitudinal cognitive surveillance, who did not have dementia were included. Participants were administered both the dCDT and a standard protocol of neuropsychological tests that measured a wide range of cognitive functions. A total of 105 features were derived from the dCDT, and their associations with 18 neuropsychological tests were assessed with linear regression models adjusted for age and sex. Associations between a composite score from dCDT features were also assessed for associations with each neuropsychological test and cognitive status (clinically diagnosed mild cognitive impairment compared to normal cognition). ResultsThe study included 2062 participants (age: mean 62, SD 13 years, 51.6% women), among whom 36 were diagnosed with mild cognitive impairment. Each neuropsychological test was associated with an average of 50 dCDT features. The composite scores derived from dCDT features were significantly associated with both neuropsychological tests and mild cognitive impairment. ConclusionsThe dCDT can potentially be used as a tool for cognitive assessment in large community-based populations.
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- 2021
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21. Neuropsychological Criteria for Mild Cognitive Impairment Improves Diagnostic Precision, Biomarker Associations, and Progression Rates
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Bondi, Mark W, Edmonds, Emily C, Jak, Amy J, Clark, Lindsay R, Delano-Wood, Lisa, McDonald, Carrie R, Nation, Daniel A, Libon, David J, Au, Rhoda, Galasko, Douglas, Salmon, David P, and Initiative, for the Alzheimer's Disease Neuroimaging
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Clinical and Health Psychology ,Psychology ,Neurodegenerative ,Dementia ,Alzheimer's Disease ,Neurosciences ,Aging ,Brain Disorders ,Clinical Research ,Behavioral and Social Science ,Acquired Cognitive Impairment ,Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD) ,Neurological ,Aged ,Aged ,80 and over ,Apolipoproteins E ,Biomarkers ,Cluster Analysis ,Cognitive Dysfunction ,Disease Progression ,Female ,Humans ,Male ,Middle Aged ,Neuropsychological Tests ,Phosphorylation ,Sensitivity and Specificity ,tau Proteins ,Alzheimer's disease ,Alzheimer's Disease Neuroimaging Initiative ,biomarker ,cluster analysis ,dementia ,mild cognitive impairment ,neuropsychology ,progression ,Clinical Sciences ,Cognitive Sciences ,Neurology & Neurosurgery ,Clinical sciences ,Biological psychology - Abstract
We compared two methods of diagnosing mild cognitive impairment (MCI): conventional Petersen/Winblad criteria as operationalized by the Alzheimer's Disease Neuroimaging Initiative (ADNI) and an actuarial neuropsychological method put forward by Jak and Bondi designed to balance sensitivity and reliability. 1,150 ADNI participants were diagnosed at baseline as cognitively normal (CN) or MCI via ADNI criteria (MCI: n = 846; CN: n = 304) or Jak/Bondi criteria (MCI: n = 401; CN: n = 749), and the two MCI samples were submitted to cluster and discriminant function analyses. Resulting cluster groups were then compared and further examined for APOE allelic frequencies, cerebrospinal fluid (CSF) Alzheimer's disease (AD) biomarker levels, and clinical outcomes. Results revealed that both criteria produced a mildly impaired Amnestic subtype and a more severely impaired Dysexecutive/Mixed subtype. The neuropsychological Jak/Bondi criteria uniquely yielded a third Impaired Language subtype, whereas conventional Petersen/Winblad ADNI criteria produced a third subtype comprising nearly one-third of the sample that performed within normal limits across the cognitive measures, suggesting this method's susceptibility to false positive diagnoses. MCI participants diagnosed via neuropsychological criteria yielded dissociable cognitive phenotypes, significant CSF AD biomarker associations, more stable diagnoses, and identified greater percentages of participants who progressed to dementia than conventional MCI diagnostic criteria. Importantly, the actuarial neuropsychological method did not produce a subtype that performed within normal limits on the cognitive testing, unlike the conventional diagnostic method. Findings support the need for refinement of MCI diagnoses to incorporate more comprehensive neuropsychological methods, with resulting gains in empirical characterization of specific cognitive phenotypes, biomarker associations, stability of diagnoses, and prediction of progression. Refinement of MCI diagnostic methods may also yield gains in biomarker and clinical trial study findings because of improvements in sample compositions of 'true positive' cases and removal of 'false positive' cases.
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- 2014
22. Dysexecutive difficulty and subtle everyday functional disabilities: the digital Trail Making Test.
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Libon, David J., Swenson, Rod, Tobyne, Sean, Jannati, Ali, Schulman, Daniel, Price, Catherine C., Lamar, Melissa, and Pascual-Leone, Alvaro
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TRAIL Making Test ,TECHNOLOGY assessment ,NEUROPSYCHOLOGICAL tests ,DISABILITIES ,FACTOR analysis - Abstract
Background: Digital neuropsychological tests reliably capture real-time, process-based behavior that traditional paper/pencil tests cannot detect, enabling earlier detection of neurodegenerative illness. We assessed relations between informant-based subtle and mild functional decline and process-based features extracted from the digital Trail Making Test-Part B (dTMT-B). Methods: A total of 321 community-dwelling participants (56.0% female) were assessed with the Functional Activities Questionnaire (FAQ) and the dTMT-B. Three FAQ groups were constructed: FAQ = 0 (unimpaired); FAQ = 1-4 (subtle impairment); FAQ = 5-8 (mild impairment). Results: Compared to the FAQ-unimpaired group, other groups required longer pauses inside target circles (p < 0.050) and produced more total pen strokes to complete the test (p < 0.016). FAQ-subtle participants required more time to complete the entire test (p < 0.002) and drew individual lines connecting successive target circles slower (p < 0.001) than FAQ-unimpaired participants. Lines connecting successive circle targets were less straight among FAQ-mild, compared to FAQ-unimpaired participants (p < 0.044). Using stepwise nominal regression (reference group = FAQ-unimpaired), pauses inside target circles classified other participants into their respective groups (p < 0.015, respectively). Factor analysis using six dTMT-B variables (oblique rotation) yielded a two-factor solution related to impaired motor/cognitive operations (48.96% variance explained) and faster more efficient motor/cognitive operations (28.88% variance explained). Conclusion: Digital assessment technology elegantly quantifies occult, nuanced behavior not previously appreciated, operationally defines critical underlying neurocognitive constructs related to functional abilities, and yields selected process-based scores that outperform traditional paper/pencil test scores for participant classification. When brought to scale, the dTMT-B test could be a sensitive tool to detect subtle-to-mild functional deficits in emergent neurodegenerative illnesses. [ABSTRACT FROM AUTHOR]
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- 2024
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23. A Chronic Increase in Blood-Brain Barrier Permeability Facilitates Intraneuronal Deposition of Exogenous Bloodborne Amyloid-Beta1–42 Peptide in the Brain and Leads to Alzheimer's Disease-Relevant Cognitive Changes in a Mouse Model.
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Acharya, Nimish K., Grossman, Henya C., Clifford, Peter M., Levin, Eli C., Light, Kenneth R., Choi, Hana, Swanson II, Randel L., Kosciuk, Mary C., Venkataraman, Venkat, Libon, David J., Matzel, Louis D., and Nagele, Robert G.
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ALZHEIMER'S disease ,PEPTIDES ,BLOOD-brain barrier ,PATHOLOGICAL physiology ,LABORATORY mice ,MIND-wandering ,MILD cognitive impairment ,ANTINUCLEAR factors - Abstract
Background: Increased blood-brain barrier (BBB) permeability and amyloid-β (Aβ) peptides (especially Aβ
1–42 ) (Aβ42 ) have been linked to Alzheimer's disease (AD) pathogenesis, but the nature of their involvement in AD-related neuropathological changes leading to cognitive changes remains poorly understood. Objective: To test the hypothesis that chronic extravasation of bloodborne Aβ42 peptide and brain-reactive autoantibodies and their entry into the brain parenchyma via a permeable BBB contribute to AD-related pathological changes and cognitive changes in a mouse model. Methods: The BBB was rendered chronically permeable through repeated injections of Pertussis toxin (PT), and soluble monomeric, fluorescein isothiocyanate (FITC)-labeled or unlabeled Aβ42 was injected into the tail-vein of 10-month-old male CD1 mice at designated intervals spanning ∼3 months. Acquisition of learned behaviors and long-term retention were assessed via a battery of cognitive and behavioral tests and linked to neuropathological changes. Results: Mice injected with both PT and Aβ42 demonstrated a preferential deficit in the capacity for long-term retention and an increased susceptibility to interference in selective attention compared to mice exposed to PT or saline only. Immunohistochemical analyses revealed increased BBB permeability and entry of bloodborne Aβ42 and immunoglobulin G (IgG) into the brain parenchyma, selective neuronal binding of IgG and neuronal accumulation of Aβ42 in animals injected with both PT and Aβ42 compared to controls. Conclusion: Results highlight the potential synergistic role of BBB compromise and the influx of bloodborne Aβ42 into the brain in both the initiation and progression of neuropathologic and cognitive changes associated with AD. [ABSTRACT FROM AUTHOR]- Published
- 2024
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24. Regional leukoaraiosis and cognition in non-demented older adults
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Wiggins, Margaret E., Tanner, Jared, Schwab, Nadine, Crowley, Samuel J., Schmalfuss, Ilona, Brumback, Babette, Libon, David J., Heilman, Kenneth, and Price, Catherine C.
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- 2019
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25. Investigating the separate and interactive associations of trauma and depression on neurocognition in urban dwelling adults
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Karstens, Aimee James, Rubin, Leah H., Shankman, Stewart A., Ajilore, Olusola, Libon, David J., Kumar, Anand, and Lamar, Melissa
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- 2017
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26. Comparing Cognitive Tests and Smartphone-Based Assessment in 2 US Community-Based Cohorts.
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De Anda-Duran, Ileana, Sunderaraman, Preeti, Searls, Edward, Moukaled, Shirine, Xuanyi Jin, Popp, Zachary, Karjadi, Cody, Hwang, Phillip H., Huitong Ding, Devine, Sherral, Shih, Ludy C., Low, Spencer, Honghuang Lin, Kolachalama, Vijaya B., Bazzano, Lydia, Libon, David J., and Au, Rhoda
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- 2024
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27. Using digital assessment technology to detect neuropsychological problems in primary care settings.
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Libon, David J., Matusz, Emily Frances, Cosentino, Stephanie, Price, Catherine C., Swenson, Rod, Vermeulen, Meagan, Ginsberg, Terrie Beth, Obiageli Okoli-Umeweni, Adaora, Powell, Leonard, Nagele, Robert, Tobyne, Sean, Rios Gomes-Osman, Joyce, and Pascual-Leone, Alvaro
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PSYCHOLOGICAL distress ,TECHNOLOGY assessment ,RECOLLECTION (Psychology) ,PRIMARY care ,DIGITAL technology ,MEDICAL specialties & specialists - Abstract
Introduction: Screening for neurocognitive impairment and psychological distress in ambulatory primary and specialty care medical settings is an increasing necessity. The Core Cognitive EvaluationTM (CCE) is administered/ scored using an iPad, requires approximately 8 min, assesses 3- word free recall and clock drawing to command and copy, asks questions about lifestyle and health, and queries for psychological distress. This information is linked with patients' self-reported concerns about memory and their cardiovascular risks. Methods: A total of 199 ambulatory patients were screened with the CCE as part of their routine medical care. The CCE provides several summary indices, and scores on 44 individual digital clock variables across command and copy tests conditions. Results: Subjective memory concerns were endorsed by 41% of participants. Approximately 31% of participants reported psychological distress involving loneliness, anxiety, or depression. Patients with self-reported memory concerns scored lower on a combined delay 3- word/ clock drawing index (p < 0.016), the total summary clock drawing command/ copy score (p < 0.050), and clock drawing to command Drawing Efficiency (p < 0.036) and Simple and Complex Motor (p < 0.029) indices. Patients treated for diabetes and atherosclerotic cardiovascular disease (ASCVD) scored lower on selected CCE outcome measures (p < 0.035). Factor analyses suggest that approximately 10 underlying variables can explain digital clock drawing performance. Discussion: The CCE is a powerful neurocognitive assessment tool that is sensitive to patient's subjective concerns about possible decline in memory, mood symptoms, possible cognitive impairment, and cardiovascular risk. iPad administration ensures total reliability for test administration and scoring. The CCE is easily deployable in outpatient ambulatory primary care settings. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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28. Feasibility and Rationale for Incorporating Frailty and Cognitive Screening Protocols in a Preoperative Anesthesia Clinic
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Amini, Shawna, Crowley, Samuel, Hizel, Loren, Arias, Franchesca, Libon, David J., Tighe, Patrick, Giordano, Chris, Garvan, Cynthia W., Enneking, F. Kayser, and Price, Catherine C.
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- 2019
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29. Cognitive and connectome properties detectable through individual differences in graphomotor organization
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Lamar, Melissa, Ajilore, Olusola, Leow, Alex, Charlton, Rebecca, Cohen, Jamie, GadElkarim, Johnson, Yang, Shaolin, Zhang, Aifeng, Davis, Randall, Penney, Dana, Libon, David J., and Kumar, Anand
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- 2016
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30. Clock Drawing Performance Slows for Older Adults After Total Knee Replacement Surgery
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Hizel, Loren P., Warner, Eric D., Wiggins, Margaret E., Tanner, Jared J., Parvataneni, Hari, Davis, Randall, Penney, Dana L., Libon, David J., Tighe, Patrick, Garvan, Cynthia W., and Price, Catherine C.
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- 2018
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31. Clock Drawing Performance Slows for Older Adults After Total Knee Replacement Surgery
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Hizel, Loren P., Warner, Eric D., Wiggins, Margaret E., Tanner, Jared J., Parvataneni, Hari, Davis, Randall, Penney, Dana L., Libon, David J., Tighe, Patrick, Garvan, Cynthia W., and Price, Catherine C.
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- 2019
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32. Contributions of Cardiovascular Burden, Peripheral Inflammation, and Brain Integrity on Digital Clock Drawing Performance in Non-Demented Older Adults.
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Dion, Catherine, Tanner, Jared J., Libon, David J., and Price, Catherine C.
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C-reactive protein ,TUMOR necrosis factors ,VASCULAR dementia ,ENTORHINAL cortex ,INFLAMMATION ,DISEASE risk factors - Abstract
Background: Greater cardiovascular burden and peripheral inflammation are associated with dysexecutive neuropsychological profiles and a higher likelihood of conversion to vascular dementia. The digital clock drawing test (dCDT) is useful in identifying neuropsychological dysfunction related to vascular etiology. However, the specific cognitive implications of the combination of cardiovascular risk, peripheral inflammation, and brain integrity remain unknown. Objective: We aimed to examine the role of cardiovascular burden, inflammation, and MRI-defined brain integrity on dCDT latency and graphomotor metrics in older adults. Methods: 184 non-demented older adults (age 69±6, 16±3 education years, 46% female, 94% white) completed dCDT, vascular assessment, blood draw, and brain MRI. dCDT variables of interest: total completion time (TCT), pre-first hand latency, digit misplacement, hour hand distance from center, and clock face area. Cardiovascular burden was calculated using the Framingham Stroke Risk Profile (FSRP-10). Peripheral inflammation markers included interleukin (IL)-6, IL-8, IL-10, tumor necrosis factor-alpha, and high sensitivity C-reactive protein. Brain integrity included bilateral entorhinal cortex volume, lateral ventricular volume, and whole brain leukoaraiosis. Results: FSRP-10, peripheral inflammation, and brain integrity explained an additional 14.6% of the variance in command TCT, where FSRP-10 was the main predictor. FSRP-10, inflammatory markers, and brain integrity explained an additional 17.0% in command digit misplacement variance, with findings largely driven by FSRP-10. Conclusion: Subtle graphomotor behavior operationalized using dCDT metrics (i.e., TCT and digit misplacement) is partly explained by cardiovascular burden, peripheral inflammation, and brain integrity and may indicate vulnerability to a disease process. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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33. Specific amino acids in HIV-1 Vpr are significantly associated with differences in patient neurocognitive status
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Dampier, Will, Antell, Gregory C., Aiamkitsumrit, Benjamas, Nonnemacher, Michael R., Jacobson, Jeffrey M., Pirrone, Vanessa, Zhong, Wen, Kercher, Katherine, Passic, Shendra, Williams, Jean W., James, Tony, Devlin, Kathryn N., Giovannetti, Tania, Libon, David J., Szep, Zsofia, Ehrlich, Garth D., Wigdahl, Brian, and Krebs, Fred C.
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- 2017
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34. Multiple Chronic Conditions and Midlife Cognitive Function in Black and White Adults: The Bogalusa Heart Study.
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Moukaled, Shirine, De Anda‐Duran, Ileana, Potts, Kaitlin S, Fernandez‐Alonso, Camilo, Libon, David J, and Bazzano, Lydia
- Abstract
Background: In late‐life, multiple chronic conditions (MCCs) has been associated with cognitive decline and Alzheimer's Disease and related dementias. However, this relationship has not been investigated in a middle‐aged population, a time when MCCs first begin to develop, or in rural and low socioeconomic settings, where individuals are at a higher risk of MCCs. We examined the relationship between MCCs and midlife cognitive function among Black and White men and women from a rural, community‐based cohort in Bogalusa, Louisiana. Methods: This cross‐sectional study includes 1,223 Black (33%) and White (67%) individuals (mean age 48.10 ± 5.26; 59% female) from the Bogalusa Heart Study with a complete neuropsychological (NP) assessment, and no history of stroke. Six chronic conditions were selected from the CMS (Centers for Medicare & Medicaid Services) Data Warehouse, and defined using self‐reported data, medication use, and physiological/laboratory measures (Table 1). MCCs was defined as the coexistence of ≥2 conditions. NP performance was measured by global cognitive z‐scores (GCS) and by domain specific z‐scores for attention and processing, episodic memory, and executive function. All z‐scores were standardized for age, sex, and race. Regression models assessed the association between MCCs and cognitive outcomes, adjusting for alcohol consumption, smoking status, and education. Results: A total of 66% participants had MCCs; 44.4% (n = 543) had 2 CCs, 17.8% (n = 218) had 3 CCs, and 3.8% (n = 46) had 4+ CCs. Compared to no chronic conditions, having 2,3, and ≥4 CCs was significantly associated with poorer executive function z‐scores after adjusting for covariates (all p's < 0.05). Having three MCCs had the worst impact on executive function z‐scores (‐0.88(.20), p <0.001) (Table 2). The most prevalent conditions in this group were hypertension, dyslipidemia, and diabetes which co‐occurred in 87.7% (n = 165) of participants with three CCs. Conclusion: This study suggests that the presence of MCCs is associated with lower executive function performance as early as midlife. Hypertension and dyslipidemia commonly occur together and are particularly prevalent in midlife. These findings highlight the importance of addressing chronic conditions earlier in life, a less studied and critical time window for potential prevention of adverse cognitive outcomes in late life. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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35. Neurocognitive Operations Underlying Working Memory Abilities: An Analysis of Latency and Time-Based Parameters.
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Emrani, Sheina, Lamar, Melissa, Price, Catherine C., Swenson, Rod, Libon, David J., and Baliga, Ganesh
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COGNITIVE processing speed ,SHORT-term memory ,STIMULUS & response (Psychology) ,VERBAL memory ,EXECUTIVE function ,EPISODIC memory ,WORD recognition ,CLASSICAL test theory - Abstract
Background: The theory of executive attention (Fuster, 2015) suggests considerable plasticity regarding when specific neurocognitive operations are recruited to bring executive tasks to fruition. Objective: We tested the hypothesis that differing neurocognitive operations are recruited upon the initiation of a response, but that other distinct neurocognitive operations are recruited towards the middle or end of a response. Methods: The Backward Digit Span Test (BDST) was administered to 58 memory clinic patients (MCI, n = 22; no-MCI, n = 36). Latency to generate all correct 5-span responses was obtained. Statistical analyses found that optimal group classification was achieved using the first and third digit backward. First and third response latencies were analyzed in relation to verbal working memory (WM), visual WM, processing speed, visuospatial operations, naming/lexical access, and verbal episodic memory tests. Results: For the first response, slower latencies were associated with better performance in relation to verbal WM and visuospatial test performance. For the third response, faster latencies were associated with better processing speed and visuospatial test performance. Conclusion: Consistent with the theory of executive attention, these data show that the neurocognitive operations underlying successful executive test performance are not monolithic but can be quite nuanced with differing neurocognitive operations associated with specific time epochs. Results support the efficacy of obtaining time-based latency parameters to help disambiguate successful executive neurocognitive operations in memory clinic patients. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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36. Instrumental activities of daily living and mild cognitive impairment.
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Libon, David J., Emrani, Sheina, Matusz, Emily F., Wasserman, Victor, Perweiler, Elyse, Ginsberg, Terrie Beth, Powell, Leonard, Bezdicek, Ondrej, Swenson, Rodney, and Schmitter-Edgecombe, Maureen
- Subjects
- *
ACTIVITIES of daily living , *EPISODIC memory , *MILD cognitive impairment , *EXECUTIVE function , *NEUROPSYCHOLOGICAL tests , *CONTROL (Psychology) , *MEMORY testing - Abstract
Background: Functional impairments are a necessary requirement for the diagnosis of a dementia along with observed cognitive impairment. Comparatively, functional abilities are often relatively intact in those with mild cognitive impairment (MCI). Objective: The current research examined the associations between memory clinic participants classified as cognitively intact, amnestic MCI, and mixed/dysexecutive MCI, using Jak-Bondi criteria, and Instrumental Activities of Daily Living - Compensation Scale (IADL-C) abilities, an informant-based questionnaire that quantifies functional abilities. The associations between functional abilities as assessed with the IADL-C and performance on neuropsychological tests were also investigated. Methods: IADLC scores were obtained along with a comprehensive neuropsychological protocol on memory clinic participants (n = 100) classified as cognitively normal (CN), amnestic MCI (aMCI), or a combined mixed/dysexecutive (mixed/dys) MCI. Regression analyses were employed to determine how the IADLC related to neuropsychological test performance. Results: On the IADLC, greater functional impairment was commonly observed in the mixed/dys MCI group compared to CN participants. Furthermore, the mixed/dys MCI group had lower scores on activities such as Money and Self-Management, Travel and Event Memory subscales compared to the CN group. Linear regression analyses found greater functional impairment in relation to lower scores on executive and episodic memory tests. Conclusions: Greater functional impairment as assessed with the IADL-C appears to be disproportionately associated with dysexecutive difficulty, and to a lesser degree, episodic memory. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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37. Höffding step and beyond: The impact of visual sensory impairment on cognitive performance in neuropsychological testing of survivors of acute methanol poisoning.
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Bukacova, Katerina, Mana, Josef, Zakharov, Sergey, Diblík, Pavel, Pelclova, Daniela, Urban, Pavel, Klepiš, Petr, Klempíř, Jiří, Libon, David J., Růžička, Evžen, and Bezdicek, Ondrej
- Subjects
METHANOL ,SENSORY disorders ,DIFFERENTIAL diagnosis ,NEUROPSYCHOLOGICAL tests ,OPTIC nerve ,OPTICAL coherence tomography ,RESEARCH funding ,DESCRIPTIVE statistics ,VISION disorders ,COGNITIVE testing ,VISUAL evoked response - Abstract
BACKGROUND: Sensory deficits can result in limitations regarding how well neuropsychological test findings can be interpreted. Only a few studies have investigated the influence of vision alteration on neuropsychological tests. In 2012 the Czech Republic experienced mass methanol poisoning. Methanol metabolites cause histotoxic hypoxia to the optic nerve. OBJECTIVE: In the current study, the effect of the toxic damage on the parts of the visual pathway on visual and non-visual neuropsychological measures was investigated using electrophysiological methods (visual evoked potential (VEP) and optical coherence tomography (OCT) with retinal nerve fibre layer (RNFL) thickness measurement. METHODS: 53 individuals who experienced methanol poisoning participated in this research (76% men; ages 24 to 74 years, mean = 43.8±14.6 years; education 11.9±1.4 years). Each participant underwent comprehensive neurological, ophthalmological, and neuropsychological examinations. RESULTS: The results of mixed-effect models revealed significant small to a medium association between the Stroop test weak interference and Grooved Pegboard with the left eye global, nasal and temporal RNFL thickness. Also, medium associations between the Finger Tapping test and the Stroop test weak interference and left eye temporal RNFL, right eye temporal RNFL, and the latency P1 of VEP in the left eye were significant. CONCLUSION: The results of this study found a small to medium association (r =.15–.33; p =.010–.046) between RNFL thickness and cognitive visual test performance. Careful interpretation is suggested regarding results obtained from visual tests of the executive or motor functioning with participants with RNFL decrease or other types of early visual processing damage. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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38. Midlife Neuropsychological Profiles and Associated Vascular Risk: The Bogalusa Heart Study.
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De Anda-Duran, Ileana, Kolachalama, Vijaya B., Carmichael, Owen T., Hwang, Phillip H., Fernandez, Camilo, Au, Rhoda, Bazzano, Lydia A., and Libon, David J.
- Subjects
CAROTID intima-media thickness ,MIDDLE age ,VERBAL memory ,RECOLLECTION (Psychology) ,ALZHEIMER'S disease ,VASCULAR dementia - Abstract
Background: Individuals with Alzheimer's disease (AD) often present with coexisting vascular pathology that is expressed to different degrees and can lead to clinical heterogeneity. Objective: To examine the utility of unsupervised statistical clustering approaches in identifying neuropsychological (NP) test performance subtypes that closely correlate with carotid intima-media thickness (cIMT) in midlife. Methods: A hierarchical agglomerative and k-means clustering analysis based on NP scores (standardized for age, sex, and race) was conducted among 1,203 participants (age 48±5.3 years) from the Bogalusa Heart Study. Regression models assessed the association between cIMT ≥50
th percentile and NP profiles, and global cognitive score (GCS) tertiles for sensitivity analysis. Results: Three NP profiles were identified: Mixed-low performance [16%, n = 192], scores ≥1 SD below the mean on immediate, delayed free recall, recognition verbal memory, and information processing; Average [59%, n = 704]; and Optimal [26%, n = 307] NP performance. Participants with greater cIMT were more likely to have a Mixed-low profile [OR = 3.10, 95% CI (2.13, 4.53), p < 0.001] compared to Optimal. After adjusting for education and cardiovascular (CV) risks, results remained. The association with GCS tertiles was more attenuated [lowest (34%, n = 407) versus highest (33%, n = 403) tertile: adjusted OR = 1.66, 95% CI (1.07, 2.60), p = 0.024]. Conclusion: As early as midlife, individuals with higher subclinical atherosclerosis were more likely to be in the Mixed-low profile, underscoring the potential malignancy of CV risk as related to NP test performance, suggesting that classification approaches may aid in identifying those at risk for AD/vascular dementia spectrum illness. [ABSTRACT FROM AUTHOR]- Published
- 2023
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39. Learning classification models of cognitive conditions from subtle behaviors in the digital Clock Drawing Test
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Souillard-Mandar, William, Davis, Randall, Rudin, Cynthia, Au, Rhoda, Libon, David J., Swenson, Rodney, Price, Catherine C., Lamar, Melissa, and Penney, Dana L.
- Published
- 2016
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40. APOE Genotype Modifies the Relationship between Midlife Vascular Risk Factors and Later Cognitive Decline
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Bangen, Katherine J., Beiser, Alexa, Delano-Wood, Lisa, Nation, Daniel A., Lamar, Melissa, Libon, David J., Bondi, Mark W., Seshadri, Sudha, Wolf, Philip A., and Au, Rhoda
- Published
- 2013
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41. Early Detection of Alzheimer's Disease-Related Pathology Using a Multi-Disease Diagnostic Platform Employing Autoantibodies as Blood-Based Biomarkers.
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DeMarshall, Cassandra A., Viviano, Jeffrey, Emrani, Sheina, Thayasivam, Umashanger, Godsey, George A., Sarkar, Abhirup, Belinka, Benjamin, Libon, David J., and Nagele, Robert G.
- Subjects
ALZHEIMER'S disease ,AUTOANTIBODIES ,MILD cognitive impairment ,RECEIVER operating characteristic curves ,PATHOLOGY - Abstract
Background: Evidence for the universal presence of IgG autoantibodies in blood and their potential utility for the diagnosis of Alzheimer's disease (AD) and other neurodegenerative diseases has been extensively demonstrated by our laboratory. The fact that AD-related neuropathological changes in the brain can begin more than a decade before tell-tale symptoms emerge has made it difficult to develop diagnostic tests useful for detecting the earliest stages of AD pathogenesis. Objective: To determine the utility of a panel of autoantibodies for detecting the presence of AD-related pathology along the early AD continuum, including at pre-symptomatic [an average of 4 years before the transition to mild cognitive impairment (MCI)/AD)], prodromal AD (MCI), and mild-moderate AD stages. Methods: A total of 328 serum samples from multiple cohorts, including ADNI subjects with confirmed pre-symptomatic, prodromal, and mild-moderate AD, were screened using Luminex xMAP
® technology to predict the probability of the presence of AD-related pathology. A panel of eight autoantibodies with age as a covariate was evaluated using randomForest and receiver operating characteristic (ROC) curves. Results: Autoantibody biomarkers alone predicted the probability of the presence of AD-related pathology with 81.0% accuracy and an area under the curve (AUC) of 0.84 (95% CI = 0.78–0.91). Inclusion of age as a parameter to the model improved the AUC (0.96; 95% CI = 0.93–0.99) and overall accuracy (93.0%). Conclusion: Blood-based autoantibodies can be used as an accurate, non-invasive, inexpensive, and widely accessible diagnostic screener for detecting AD-related pathology at pre-symptomatic and prodromal AD stages that could aid clinicians in diagnosing AD. [ABSTRACT FROM AUTHOR]- Published
- 2023
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42. Sentence processing in Lewy body spectrum disorder: The role of working memory
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Gross, Rachel G., McMillan, Corey T., Chandrasekaran, Keerthi, Dreyfuss, Michael, Ash, Sharon, Avants, Brian, Cook, Philip, Moore, Peachie, Libon, David J., Siderowf, Andrew, and Grossman, Murray
- Published
- 2012
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43. Dissociating Statistically Determined Normal Cognitive Abilities and Mild Cognitive Impairment Subtypes with DCTclock.
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Matusz, Emily F., Price, Catherine C., Lamar, Melissa, Swenson, Rod, Au, Rhoda, Emrani, Sheina, Wasserman, Victor, Libon, David J., and Thompson, Louisa I.
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COGNITIVE ability ,COGNITIVE processing speed ,COGNITION disorders ,INFORMATION processing ,CLOCKS & watches - Abstract
Objective: To determine whether the DCTclock can detect differences across groups of patients seen in the memory clinic for suspected dementia. Method: Patients (n = 123) were classified into the following groups: cognitively normal (CN), subtle cognitive impairment (SbCI), amnestic cognitive impairment (aMCI), and mixed/dysexecutive cognitive impairment (mx/dysMCI). Nine outcome variables included a combined command/copy total score and four command and four copy indices measuring drawing efficiency, simple/complex motor operations, information processing speed, and spatial reasoning. Results: Total combined command/copy score distinguished between groups in all comparisons with medium to large effects. The mx/dysMCI group had the lowest total combined command/copy scores out of all groups. The mx/dysMCI group scored lower than the CN group on all command indices (p < .050, all analyses); and lower than the SbCI group on drawing efficiency (p = .011). The aMCI group scored lower than the CN group on spatial reasoning (p = .019). Smaller effect sizes were obtained for the four copy indices. Conclusions: These results suggest that DCTclock command/copy parameters can dissociate CN, SbCI, and MCI subtypes. The larger effect sizes for command clock indices suggest these metrics are sensitive in detecting early cognitive decline. Additional research with a larger sample is warranted. [ABSTRACT FROM AUTHOR]
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- 2023
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44. Differential Effects of Goal Cues on Everyday Action Errors in Alzheimer’s Disease Versus Parkinson’s Disease Dementia
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Giovannetti, Tania, Seligman, Sarah C., Britnell, Priscilla, Brennan, Laura, and Libon, David J.
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- 2015
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45. The functional connectivity and neuropsychology underlying mental planning operations: data from the digital clock drawing test.
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Dion, Catherine, Tanner, Jared J., Formanski, Erin M., Davoudi, Anis, Rodriguez, Katie, Wiggins, Margaret E., Amin, Manish, Penney, Dana, Davis, Randall, Heilman, Kenneth M., Garvan, Cynthia, Libon, David J., and Price, Catherine C.
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SEMANTICS ,NEUROPSYCHOLOGY ,LIMBIC system ,BASAL ganglia ,MILD cognitive impairment ,FUNCTIONAL connectivity ,COGNITION ,MAGNETIC resonance imaging ,ACETYLCHOLINE ,NEUROPSYCHOLOGICAL tests ,ATTENTION ,SPACE perception - Abstract
We examined the construct of mental planning by quantifying digital clock drawing digit placement accuracy in command and copy conditions, and by investigating its underlying neuropsychological correlates and functional connectivity. We hypothesized greater digit misplacement would associate with attention, abstract reasoning, and visuospatial function, as well as functional connectivity from a major source of acetylcholine throughout the brain: the basal nucleus of Meynert (BNM). Participants (n = 201) included non-demented older adults who completed all metrics within 24 h of one another. A participant subset met research criteria for mild cognitive impairment (MCI; n = 28) and was compared to non-MCI participants on digit misplacement accuracy and expected functional connectivity differences. Digit misplacement and a comparison dissociate variable of total completion time were acquired for command and copy conditions. a priori fMRI seeds were the bilateral BNM. Command digit misplacement is negatively associated with semantics, visuospatial, visuoconstructional, and reasoning (p's < 0.01) and negatively associated with connectivity from the BNM to the anterior cingulate cortex (ACC; p = 0.001). Individuals with MCI had more misplacement and less BNM-ACC connectivity (p = 0.007). Total completion time involved posterior and cerebellar associations only. Findings suggest clock drawing digit placement accuracy may be a unique metric of mental planning and provide insight into neurodegenerative disease. [ABSTRACT FROM AUTHOR]
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- 2022
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46. Microglial activation and TDP-43 pathology correlate with executive dysfunction in amyotrophic lateral sclerosis
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Brettschneider, Johannes, Libon, David J., Toledo, Jon B., Xie, Sharon X., McCluskey, Leo, Elman, Lauren, Geser, Felix, Lee, Virginia M.-Y., Grossman, Murray, and Trojanowski, John Q.
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- 2012
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47. Sparse canonical correlation analysis relates network-level atrophy to multivariate cognitive measures in a neurodegenerative population
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Avants, Brian B., Libon, David J., Rascovsky, Katya, Boller, Ashley, McMillan, Corey T., Massimo, Lauren, Coslett, Branch H., Chatterjee, Anjan, Gross, Rachel G., and Grossman, Murray
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- 2014
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48. The Boston Process Approach and Digital Neuropsychological Assessment: Past Research and Future Directions.
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Libon, David J., Swenson, Rod, Lamar, Melissa, Price, Catherine C., Baliga, Ganesh, Pascual-Leone, Alvaro, Au, Rhoda, Cosentino, Stephanie, and Andersen, Stacy L.
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ALZHEIMER'S disease , *ARTIFICIAL intelligence , *NEUROPSYCHOLOGICAL tests - Abstract
Neuropsychological assessment using the Boston Process Approach (BPA) suggests that an analysis of the strategy or the process by which tasks and neuropsychological tests are completed, and the errors made during test completion convey much information regarding underlying brain and cognition and are as important as overall summary scores. Research over the last several decades employing an analysis of process and errors has been able to dissociate between dementia patients diagnosed with Alzheimer's disease, vascular dementia associated with MRI-determined white matter alterations, and Parkinson's disease; and between mild cognitive impairment subtypes. Nonetheless, BPA methods can be labor intensive to deploy. However, the recent availability of digital platforms for neuropsychological test administration and scoring now enables reliable, rapid, and objective data collection. Further, digital technology can quantify highly nuanced data previously unobtainable to define neurocognitive constructs with high accuracy. In this paper, a brief review of the BPA is provided. Studies that demonstrate how digital technology translates BPA into specific neurocognitive constructs using the Clock Drawing Test, Backward Digit Span Test, and a Digital Pointing Span Test are described. Implications for using data driven artificial intelligence-supported analytic approaches enabling the creation of more sensitive and specific detection/diagnostic algorithms for putative neurodegenerative illness are also discussed. [ABSTRACT FROM AUTHOR]
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- 2022
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49. Behavioral and psychological symptoms, neurocognitive performance, and functional independence in mild dementia
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Gallo, Jennifer L., Schmidt, Kara S., and Libon, David J.
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Dementia -- Diagnosis ,Dementia -- Patient outcomes - Abstract
This research investigated the interrelationships between behavioral and psychological symptoms in dementia (BPSD; i.e. disturbance of perception, thought content, mood, or behavior), cognition, and functional independence among mildly demented outpatients (MMSE = 23). A comprehensive neuropsychological evaluation was administered to 48 outpatients diagnosed with Alzheimer's disease ( n = 32) and vascular dementia ( n = 16) in order to assess cognitive function. A neuropsychiatric symptom inventory assessed BPSD and an instrumental activities of daily living questionnaire assessed functional independence. Pearson correlational analyses found that BPSD were associated with dementia severity, but not with performance on tests of specific neurocognitive domains. In addition, functional independence was associated with BPSD, dementia severity, and executive control, but not with language or memory. Multiple regression analyses revealed that dementia severity alone best predicted BPSD, and that BPSD more so than dementia severity best predicted functional independence. None of the specific neurocognitive domains predicted either BPSD or functional independence., Keywords: Alzheimer's disease; BPSD; functional independence; vascular dementia 397 ArticleBehavioral and psychological symptoms, neurocognitive performance, and functional independence in mild dementia SAGE Publications, Inc.200810.1177/1471301208093291 Jennifer L.Gallo Drexel University, Philadelphia, PA, [...]
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- 2008
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50. Alterations in working memory as a function of leukoaraiosis in dementia
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Lamar, Melissa, Price, Catherine C., Libon, David J., Penney, Dana L., Kaplan, Edith, Grossman, Murray, and Heilman, Kenneth M.
- Published
- 2007
- Full Text
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