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OBJECTIVE: Dispersion is a form of intra-individual variability across neuropsychological tests that has been shown to predict cognitive decline. However, few studies have investigated the stability and predictive utility of both across- and within-domain dispersion. The current study aims to fill these gaps in the literature by examining multiple indices of dispersion in a longitudinal clinical sample of individuals diagnosed with mild cognitive impairment (MCI) at baseline. METHOD: Two hundred thirty-eight MCI patients from a cognitive disorders clinic underwent testing at baseline and after approximately 1.5 years. Linear regression was used to examine whether baseline across- and within-domain dispersion predicted cognitive decline in individuals whose diagnostic classification progressed to dementia (i.e., MCI-Decline) and those who retained an MCI diagnosis at follow-up (i.e., MCI-Stable). Cognitive decline was operationalized dichotomously using group status and continuously using standardized regression-based (SRB) z-scores. RESULTS: Dispersion variables at baseline and follow-up were positively correlated in both groups, with the exception of within-domain executive functioning and language dispersion in the MCI-Decline group. None of the dispersion variables predicted diagnostic conversion to MCI. Using SRB z-scores, greater across-domain dispersion predicted greater overall cognitive decline at follow-up, but this was not the case for within-domain variables with the exception of visuospatial skills. CONCLUSIONS: Results suggest that across- and within-domain dispersion are relatively stable across time, and that across-domain dispersion is predictive of subtle cognitive decline in patients with MCI. However, these results also highlight that findings may differ based on the tests included in dispersion calculations.
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INTRODUCTION: Manual motor problems have been reported in mild cognitive impairment (MCI) and Alzheimer's disease (AD), but the specific aspects that are affected, their neuropathology, and potential value for classification modeling is unknown. The current study examined if multiple measures of motor strength, dexterity, and speed are affected in MCI and AD, related to AD biomarkers, and are able to classify MCI or AD. METHODS: Fifty-three cognitively normal (CN), 33 amnestic MCI, and 28 AD subjects completed five manual motor measures: grip force, Trail Making Test A, spiral tracing, finger tapping, and a simulated feeding task. Analyses included (1) group differences in manual performance; (2) associations between manual function and AD biomarkers (PET amyloid ß, hippocampal volume, and APOE ε4 alleles); and (3) group classification accuracy of manual motor function using machine learning. RESULTS: Amnestic MCI and AD subjects exhibited slower psychomotor speed and AD subjects had weaker dominant hand grip strength than CN subjects. Performance on these measures was related to amyloid ß deposition (both) and hippocampal volume (psychomotor speed only). Support vector classification well-discriminated control and AD subjects (area under the curve of 0.73 and 0.77, respectively) but poorly discriminated MCI from controls or AD. CONCLUSION: Grip strength and spiral tracing appear preserved, while psychomotor speed is affected in amnestic MCI and AD. The association of motor performance with amyloid ß deposition and atrophy could indicate that this is due to amyloid deposition in and atrophy of motor brain regions, which generally occurs later in the disease process. The promising discriminatory abilities of manual motor measures for AD emphasize their value alongside other cognitive and motor assessment outcomes in classification and prediction models, as well as potential enrichment of outcome variables in AD clinical trials.
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Objectives: The vast majority of studies on aging, cognition, and dementia focus on non-Hispanic white subjects. This paper adds to the extant literature by providing insight into the African American aging experience. Here we describe the study design and baseline characteristics of the African American Dementia and Aging Project (AADAPt) study, which is exploring aging and cognition in African American older adults in Oregon. Methods: African American older adults (n=177) participated in AADAPt, a longitudinal study that collected data on cognitive, physical, and social functioning in annual visits since 2000. Results: AADAPt participants had risk factors for developing dementia in future, such as hypertension and hyperlipidemia, but also reported protective factors such as high social engagement. Conclusions: The AADAPt project offers new insights into aging in older African Americans that includes data on cognition, social engagement, and physical health, which are crucial for understanding the experience of under-represented groups and making future studies more inclusive. These findings reflect a window of time for a geographically-focused cohort, and the lessons learned from this study likely have broader implications for shaping the health of these older African American adults. Keywords: African American, Dementia, Observational Study.
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Background: Practice effects on cognitive testing in mild cognitive impairment (MCI) and Alzheimer's disease (AD) remain understudied, especially with how they compare to biomarkers of AD. Objective: The current study sought to add to this growing literature. Methods: Cognitively intact older adults (nâ=â68), those with amnestic MCI (nâ=â52), and those with mild AD (nâ=â45) completed a brief battery of cognitive tests at baseline and again after one week, and they also completed a baseline amyloid PET scan, a baseline MRI, and a baseline blood draw to obtain APOE É4 status. Results: The intact participants showed significantly larger baseline cognitive scores and practice effects than the other two groups on overall composite measures. Those with MCI showed significantly larger baseline scores and practice effects than AD participants on the composite. For amyloid deposition, the intact participants had significantly less tracer uptake, whereas MCI and AD participants were comparable. For total hippocampal volumes, all three groups were significantly different in the expected direction (intactâ>âMCIâ>âAD). For APOE É4, the intact had significantly fewer copies of É4 than MCI and AD. The effect sizes of the baseline cognitive scores and practice effects were comparable, and they were significantly larger than effect sizes of biomarkers in 7 of the 9 comparisons. Conclusion: Baseline cognition and short-term practice effects appear to be sensitive markers in late life cognitive disorders, as they separated groups better than commonly-used biomarkers in AD. Further development of baseline cognition and short-term practice effects as tools for clinical diagnosis, prognostic indication, and enrichment of clinical trials seems warranted.
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Enfermedad de Alzheimer , Biomarcadores , Disfunción Cognitiva , Imagen por Resonancia Magnética , Pruebas Neuropsicológicas , Tomografía de Emisión de Positrones , Humanos , Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/diagnóstico por imagen , Masculino , Femenino , Anciano , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/sangre , Biomarcadores/sangre , Anciano de 80 o más Años , Apolipoproteína E4/genética , Práctica Psicológica , Cognición/fisiología , Hipocampo/diagnóstico por imagen , Hipocampo/patologíaRESUMEN
Objective: Essential tremor (ET), while defined by progressive motor symptoms, is increasingly associated with cognitive impairments (e.g. attention, memory, and executive functions). This study characterizes the cognitive profile of individuals with ET on the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), a commonly-used neuropsychological screening measure. Method: Seventy-seven individuals (mean age: 70.6, 34% female) diagnosed with ET and being considered for surgical/procedural intervention were recruited from a Movement Disorders Clinic. All participants completed the RBANS, Grooved Pegboard Test (GPB), and Fahn, Tolosa, Marin Tremor Scale (FTMTS) in the clinical evaluation of their tremor. Results: One-sample t-tests found Immediate Memory, Language, Attention, and Total Scale Index scores to be significantly lower than the expected population mean (p < .05). List Learning, Semantic Fluency, Coding, and List Recall subtests were significantly lower and Picture Naming was significantly higher than the expected population mean (p < .05). GPB scores were correlated with the Attention Index as well as List Learning and Coding subtests. FTMTS Severity was correlated with the Coding subtest and FTMTS Disability was correlated with the Figure Recall subtest. Conclusions: Results support prior literature indicating cognitive weaknesses in those with ET. Individuals with ET had poorer global cognitive abilities, with specific decrements in Immediate Memory, Attention, and Language. Notably, the Attention Index and Coding subtest were most affected by motor functioning. Cognitive screening measures, like the RBANS, can efficiently identify strengths and weaknesses in individuals with ET seeking surgical/procedural interventions.
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Trastornos del Conocimiento , Temblor Esencial , Humanos , Femenino , Anciano , Masculino , Trastornos del Conocimiento/diagnóstico , Temblor Esencial/diagnóstico , Temblor Esencial/complicaciones , Temblor/complicaciones , Pruebas Neuropsicológicas , CogniciónRESUMEN
Objective: Iverson (2001) expanded on reliable change methodology by accounting for the variability in scores at Time 2 in the calculation of change scores. However, due to limitations in available data, an incomplete picture of variables affecting change was presented. The current paper sought to address some of these limitations and clarify the methodology for assessing reliable change. Method: Using one-year test-retest data on the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) in older adults who were cognitively intact or had mild Alzheimer's disease (AD), change scores were calculated, and various models, consistent with or divergent from Iverson, were presented. Results: Across the RBANS, individuals with intact cognition tended to show less variable scores, especially at Time 2, which resulted in larger change scores than those with AD. When applied to an independent sample, different patterns of change were observed, with: (1) models that used intact data showed more cognitive change than those using AD data; (2) the model that corrected for practice effects and used intact data showed the most decline; and (3) the model that corrected for practice effects and used AD data showed the most improvement. The models that showed the strongest association in classifying independent cases as decline/stable/improve were those that used intact data and were discordant on the use of practice effects. Conclusions: Overall, findings highlight the complexity of calculating reliable change, and they lend additional caution to Iverson's original limitations. However, the use of data from individuals classified as cognitively intact and a correction for practice effects seems warranted.
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Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Anciano , Pruebas Neuropsicológicas , Cognición , Enfermedad de Alzheimer/psicología , Disfunción Cognitiva/psicologíaRESUMEN
Practice effects have become a potentially important variable regarding the diagnosis, prognosis, and treatment recommendations in mild cognitive impairment (MCI) and Alzheimer's disease (AD). However, the understanding of these short-term changes in test scores remains unclear. The current observational study sought to examine variables that influence the magnitude of short-term practice effects in MCI and AD, including demographic information, cognitive performance, daily functioning, and medical comorbidities. One hundred sixty-six older adults classified as cognitively intact, amnestic MCI, or mild AD were tested twice across 1 week with a brief battery of neuropsychological tests. Correlational and regression analyses examined the relationship of practice effects with demographic and clinical variables. Results indicated that practice effects were minimally related to demographic variables and medical comorbidities, but they were significantly related to cognitive variables, depressive symptoms, and daily functioning. These findings expand our understanding of practice effects in MCI and AD, and they may allow a better appreciation of how they could affect clinical care and research.
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Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Anciano , Enfermedad de Alzheimer/psicología , Pruebas Neuropsicológicas , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/psicología , PronósticoRESUMEN
BACKGROUND: Despite reports of gross motor problems in mild cognitive impairment (MCI) and Alzheimer's disease (AD), fine motor function has been relatively understudied. OBJECTIVE: We examined if finger tapping is affected in AD, related to AD biomarkers, and able to classify MCI or AD. METHODS: Forty-seven cognitively normal, 27 amnestic MCI, and 26 AD subjects completed unimanual and bimanual computerized tapping tests. We tested 1) group differences in tapping with permutation models; 2) associations between tapping and biomarkers (PET amyloid-ß, hippocampal volume, and APOEÉ4 alleles) with linear regression; and 3) the predictive value of tapping for group classification using machine learning. RESULTS: AD subjects had slower reaction time and larger speed variability than controls during all tapping conditions, except for dual tapping. MCI subjects performed worse than controls on reaction time and speed variability for dual and non-dominant hand tapping. Tapping speed and variability were related to hippocampal volume, but not to amyloid-ß deposition or APOEÉ4 alleles. Random forest classification (overall accuracyâ=â70%) discriminated control and AD subjects, but poorly discriminated MCI from controls or AD. CONCLUSIONS: MCI and AD are linked to more variable finger tapping with slower reaction time. Associations between finger tapping and hippocampal volume, but not amyloidosis, suggest that tapping deficits are related to neuropathology that presents later during the disease. Considering that tapping performance is able to differentiate between control and AD subjects, it can offer a cost-efficient tool for augmenting existing AD biomarkers.
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Enfermedad de Alzheimer , Amiloidosis , Disfunción Cognitiva , Humanos , Enfermedad de Alzheimer/psicología , Péptidos beta-Amiloides , Disfunción Cognitiva/psicología , BiomarcadoresRESUMEN
INTRODUCTION: Within clinical neuropsychology, a classic diagnostic distinction is made between cortical and subcortical disorders, especially based on their memory profiles. Typically, this is based on the comparison of recall and recognition trials, where individuals with cortical conditions do not tend to benefit (i.e., score well) on recognition trials and individuals with subcortical conditions do. Although the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) is a widely used brief cognitive battery, there is a lack of evidence to support this measure's utility in distinguishing between the memory profiles of these conditions. METHOD: Thirty-six mild Alzheimer's disease (AD), 55 Parkinson's disease (PD), and 105 essential tremor (ET) participants (N = 196) were administered the RBANS with additional Story and Figure Recognition subtests. Group differences on recall and recognition scores (Total Correct, Hits or True Positives, False Positive Errors, and discriminability index) were examined across the three groups, while controlling for the influence of age and gender. RESULTS: As expected, individuals with AD had poorer recognition scores compared to the other clinical groups across tasks (all p-values < .05), while the ET sample largely performed comparably to the PD sample. With the exception of comparable Figure Recognition and Recall in the PD sample, all groups exhibited significantly greater recognition Hit performance compared to Recall (all p-values < .05). CONCLUSIONS: The group differences in performance across RBANS recognition subtests suggest support for traditional "cortical" and "subcortical" profiles. However, all groups, including the mild AD sample, demonstrated a benefit from recognition cues compared to free recall. Overall, these findings support the inclusion of the newly developed Story and Figure Recognition subtests in future clinical practice and research endeavors.
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Enfermedad de Alzheimer , Enfermedad de Parkinson , Humanos , Reconocimiento en Psicología , Recuerdo Mental , Enfermedad de Alzheimer/diagnóstico , Señales (Psicología)RESUMEN
Adults with Mild Cognitive Impairment (MCI) and Alzheimer's disease (AD) have increased rates of Obstructive Sleep Apnea (OSA). Positive Airway Pressure (PAP) is the first-line treatment for OSA and may have potential benefits for slowing cognitive decline in these individuals. However, adherence is low in PAP users overall and those with cognitive impairment may have unique challenges. Furthermore, there has been little systematic study of the use of PAP or strategies to enhance PAP adherence among those with AD or MCI. The aim of this review is to examine existing observational, quasi-experimental and experimental studies of the effects of PAP on cognitive function. In addition, our goal was to gather evidence about the adherence rates, and support for PAP among adults with MCI and mild to moderate AD. Through searches of electronic databases (University of Utah Library, SAGE Publishing, PubMed, Wiley, EBSCO, Science Direct, ProQuest, and NCBI), we identified 11 articles that fit our study inclusion criteria. Synthesis of data was performed with a focus on cognitive outcomes of PAP interventions and adherence. Findings from the studies showed that multiple indices of memory improved with PAP use. Adherence in MCI and AD populations was largely comparable to adherence reported in general adult populations, but more research is needed to optimize systems for providing support for PAP users and caregivers. Results support PAP as a promising intervention in this population but more research is needed to make definitive conclusions about the relationship between PAP use and improved cognitive function. Furthermore, research is needed to determine if additional interventions are needed to support patients and caregivers.
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Disfunción Cognitiva , Apnea Obstructiva del Sueño , Adulto , Humanos , Resultado del Tratamiento , Cooperación del Paciente , Disfunción Cognitiva/terapia , Presión de las Vías Aéreas Positiva Contínua/métodos , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/terapia , Apnea Obstructiva del Sueño/psicologíaRESUMEN
BACKGROUND: Cognitive change in mild cognitive impairment (MCI), a likely prodrome to Alzheimer's disease, can be tracked with repeated neuropsychological assessments, but there has been little work quantifying these changes over time. Cognitive change can be statistically examined using standardized regression-based (SRB) formulas, which yield a z-score indicating amount of change compared to a normative group. OBJECTIVE: To use SRB z-scores to quantify cognitive change in a sample of patients classified as MCI at baseline, and to compare cognitive change in those who remained MCI on follow-up (MCI-Stable) and those who progressed to dementia (MCI-Decline). METHODS: Using 283 MCI patients from a cognitive disorders clinic who were re-assessed after approximately one- and one-half years, SRB z-scores were calculated for each test in a comprehensive neuropsychological battery for each participant. RESULTS: There was a significant decline between timepoints across all cognitive tests, with the greatest amount of decline on tests of learning and memory. Group differences were seen on nearly all cognitive tests, with the MCI-Decline group showing more decline (i.e., significantly larger and negative z-scores) than the MCI-Stable participants. Notable cognitive decline was also observed in the MCI-Stable group, with z-scores ranging from -0.01 - -2.24 compared to normative data. CONCLUSION: This study highlights the amount of cognitive decline that occurs in MCI, including for those who remain "stable" and those who progress to dementia. It also demonstrates the value of the SRB method in more clearly quantifying cognitive decline, which may help identify individuals most vulnerable to MCI progression.
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Enfermedad de Alzheimer , Trastornos del Conocimiento , Disfunción Cognitiva , Humanos , Progresión de la Enfermedad , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/psicología , Enfermedad de Alzheimer/diagnóstico , Trastornos del Conocimiento/psicología , Pruebas Neuropsicológicas , CogniciónRESUMEN
BACKGROUND: The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) has been associated with commonly used biomarkers of Alzheimer's disease (AD), including brain amyloid plaque density. However, less is known about if changes in the RBANS across time are also related to brain amyloid deposition. The current study sought to expand on prior work by examining the relationship between changes over time on the RBANS and amyloid deposition via positron emission tomography (PET). METHOD: One-hundred twenty-six older adults with intact or impaired cognition and daily functioning underwent repeat assessment with the RBANS across nearly 16 months, as well as had a baseline amyloid PET scan. RESULTS: In the entire sample, amyloid deposition was significantly related to change on all five Indexes and the Total Scale score of the RBANS, with greater amyloid being associated with worsening cognition. This pattern was also observed in 11 of 12 subtests. CONCLUSIONS: Whereas prior studies have identified a relationship between baseline RBANS and amyloid status, the current findings support that changes in the RBANS are also indicative of AD brain pathology, even if these findings are mediated by cognitive status. Although replication in a more diverse sample is needed, these results continue to support the use of the RBANS in AD clinical trials.
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Enfermedad de Alzheimer , Trastornos del Conocimiento , Disfunción Cognitiva , Humanos , Anciano , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/complicaciones , Trastornos del Conocimiento/psicología , Enfermedad de Alzheimer/complicaciones , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/patología , Pruebas NeuropsicológicasRESUMEN
BACKGROUND: The Quick Dementia Rating System (QDRS) is a brief, informant-reported dementia staging tool that approximates scores on the Clinical Dementia Rating Scale in patients with Alzheimer's disease (AD). OBJECTIVE: The current study sought to examine change in the QDRS across time, which is necessary for clinical and research efforts. METHODS: One-hundred ten older adults (intact, mild cognitive impairment [MCI], mild AD, classified with Alzheimer's Disease Neuroimaging Initiative criteria) were rated on the QDRS by an informant and had an amyloid positron emission tomography scan at baseline. The informant re-rated each participant on the QDRS after one year. Dependent t-tests compared the entire sample and various subgroups (e.g., cognitive status, amyloid status) on baseline and follow-up QDRS scores. RESULTS: In the entire sample, the Total score on the QDRS significantly increased (i.e., worsened) on follow-up (pâ<â0.001). When subgroups were analyzed, the MCI and mild AD subjects showed increasing (i.e., worsening) QDRS Total scores (both pâ<â0.001), but the intact subjects remained stable over time (pâ=â0.28). Additionally, those classified as being amyloid positive at baseline showed significantly increased QDRS Total scores at follow-up (pâ<â0.001) compared to those who were amyloid negative at baseline, whose QDRS Total scores remained stable over time (pâ=â0.63). CONCLUSION: The QDRS can potentially demonstrate worsening functioning status across one year, especially in those who have MCI or mild AD and those who are amyloid positive. Therefore, the current results preliminarily suggest that the QDRS may provide an efficient tool for tracking progression in clinical trials in AD.
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Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Anciano , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/psicología , Progresión de la Enfermedad , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/psicología , Neuroimagen , Pruebas de Estado Mental y Demencia , Péptidos beta-AmiloidesRESUMEN
INTRODUCTION: The mechanisms linking motor function to Alzheimer's disease (AD) progression have not been well studied, despite evidence of AD pathology within motor brain regions. Thus, there is a need for new motor measure that is sensitive and specific to AD. METHODS: In a sample of 121 older adults (54 cognitive unimpaired [CU], 35 amnestic Mild Cognitive Impairment [aMCI], and 32 probable mild AD), intrasubject standard deviation (ISD) across six trials of a novel upper-extremity motor task was predicted with volumetric regional gray matter and neuropsychological scores using classification and regression tree (CART) analyses. RESULTS: Both gray matter and neuropsychological CART models indicated that motor task ISD (our measure of motor learning) was related to cortical regions and cognitive test scores associated with memory, executive function, and visuospatial skills. CART models also accurately distinguished motor task ISD of MCI and probable mild AD from CU. DISCUSSION: Variability in motor task performance across practice trials may be valuable for understanding preclinical and early-stage AD.
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Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Anciano , Enfermedad de Alzheimer/diagnóstico por imagen , Disfunción Cognitiva/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética , Pruebas NeuropsicológicasRESUMEN
Recently, two new recognition subtests for the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) were developed and initially validated in a cohort of older adults who were cognitively intact or classified as amnestic Mild Cognitive Impairment (MCI) or mild Alzheimer's disease (AD). The current paper extends that validation by comparing the recall and recognition subtests of the RBANS, including the existing and recently developed scores, to three commonly used biomarkers in AD in an expanded sample from the initial validation. One hundred fifty-four older adults (65 intact, 46 MCI, 43 AD) were administered the RBANS, which included the recently developed subtests for Story Recognition and Figure Recognition (hits, false positives, total correct), as part of a study on memory and biomarkers. Participants also completed magnetic resonance imaging to obtain hippocampal volumes, positron emission tomography to obtain amyloid plaque deposition, and a blood draw to obtain APOE ε4 status. Whereas correlations between recall scores and biomarkers tended to be moderate (average r = ±0.48), these correlations were comparable across the three recognition total scores (average r = ±0.42), but tended to be lower for recognition hits (average r = ±0.28) and false positives (average r = ±0.38). These results further validate the existing and recently developed recognition scores on the RBANS as providing useful information about brain and genetic pathology in older adults with intact and impaired cognitive functioning.
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Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Anciano , Enfermedad de Alzheimer/psicología , Disfunción Cognitiva/psicología , Recuerdo Mental , Biomarcadores , Pruebas NeuropsicológicasRESUMEN
The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) has been associated with commonly used biomarkers of Alzheimer's disease (AD). However, prior studies have typically utilized small and poorly characterized samples, and they have not analyzed the subtests of the RBANS. The current study sought to expand on prior work by examining the relationship between the Indexes and subtest scores of the RBANS and three AD biomarkers: amyloid deposition via positron emission tomography, hippocampal volume via magnetic resonance imaging, and APOE ε4 status.One-hundred twenty-one older adults across the AD continuum (intact, amnestic Mild Cognitive Impairment, mild AD), who were mostly Caucasian and well-educated, underwent assessment with the RBANS and collection of the three biomarkers.Greater amyloid deposition was significantly related to lower scores on all five Indexes and the Total Scale score of the RBANS, as well as 11 of 12 subtests. For bilateral hippocampal volume, significant correlations were observed for 4 of the 5 Indexes, Total Scale score, and 9 of 12 subtests, with smaller hippocampi being related to lower RBANS scores. Participants with at least one APOE ε4 allele had significantly lower scores on 3 of the 5 Indexes, Total Scale score, and 8 of the 12 subtests.In this sample of participants across the dementia spectrum, most RBANS Indexes and subtests showed relationships with the amyloid deposition, hippocampal volumes, and APOE status, with poorer performance on the RBANS being associated with biomarker positivity. Although memory scores on the RBANS have traditionally been linked to biomarkers in AD, other Index and subtest scores also hold promise as indicators of AD. Replication in a more diverse sample is needed.
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Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Anciano , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/genética , Apolipoproteína E4/genética , Pruebas Neuropsicológicas , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/genética , BiomarcadoresRESUMEN
Standard dosages of motor practice in clinical physical rehabilitation are insufficient to optimize motor learning, particularly for older patients who often learn at a slower rate than younger patients. Personalized practice dosing (i.e., practicing a task to or beyond one's plateau in performance) may provide a clinically feasible method for determining a dose of practice that is both standardized and individualized, and may improve motor learning. The purpose of this study was to investigate whether personalized practice dosages [practice to plateau (PtP) and overpractice (OVP)] improve retention and transfer of a motor task, compared to low dose [LD] practice that mimics standard clinical dosages. In this pilot randomized controlled trial (NCT02898701, ClinicalTrials.gov), community-dwelling older adults (n = 41, 25 female, mean age 68.9 years) with a range of balance ability performed a standing serial reaction time task in which they stepped to specific targets. Presented stimuli included random sequences and a blinded repeating sequence. Participants were randomly assigned to one of three groups: LD (n = 15, 6 practice trials equaling 144 steps), PtP (n = 14, practice until reaching an estimated personal plateau in performance), or OVP (n = 12, practice 100% more trials after reaching an estimated plateau in performance). Measures of task-specific learning (i.e., faster speed on retention tests) and transfer of learning were performed after 2-4 days of no practice. Learning of the random sequence was greater for the OVP group compared to the LD group (p = 0.020). The OVP (p = 0.004) and PtP (p = 0.010) groups learned the repeated sequence more than the LD group, although the number of practice trials across groups more strongly predicted learning (p = 0.020) than did group assignment (OVP vs. PtP, p = 0.270). No group effect was observed for transfer, although significant transfer was observed in this study as a whole (p < 0.001). Overall, high and personalized dosages of postural training were well-tolerated by older adults, suggesting that this approach is clinically feasible. Practicing well-beyond standard dosages also improved motor learning. Further research should determine the clinical benefit of this personalized approach, and if one of the personalized approaches (PtP vs. OVP) is more beneficial than the other for older patients.
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Even though impaired visuospatial abilities can negatively affect daily functioning, there are very few training programs that attempt to improve visuospatial abilities. The purpose of this study was to examine if a single training session with a computerized version of the Corsi Block Tapping Task could improve mental rotation skills. Fifty-three young adults were assigned to one of two groups: (1) control group (mean age = 21.4; 10 females), who had 20 min of rest after their baseline assessment, or (2) training group (mean age = 21.5; 17 females), who had 20 min of training on the Corsi Block Tapping Task after their baseline assessment. The primary outcome was reaction time on a computer-based mental rotation task, and it was assessed both before and after the rest or training. There was a significant interaction between time (pre vs. post) and group (control vs. training) on mental rotation performance (p = 0.04), with the training group performing on average 124 ms faster on accurate trials than the control group at post-test. This preliminary study suggested that improving mental rotation may be feasible through targeted cognitive training. Future studies will consider multiple sessions of Corsi Block Tapping Task training to maximize training benefits (i.e., dose-response), as well as longer term retention in cognitively intact and impaired individuals.
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Trastornos del Conocimiento , Navegación Espacial , Adulto Joven , Femenino , Humanos , Adulto , Memoria a Corto Plazo/fisiologíaRESUMEN
BACKGROUND: Obstructive sleep apnea (OSA) is a serious health condition that affects approximately 30-50% of older adults and contributes to risk for cardiometabolic disorders and dementia. Despite the well-documented role of partners in treatment seeking and adherence to positive airway pressure (PAP), treatments for OSA have nearly exclusively focused on the patient and current treatments for OSA do not address co-existing sleep problems such as insomnia that are prevalent in both patients with OSA and their partners. Therefore, the goal of this study is to develop and test a novel couples-based sleep health intervention to promote adherence to PAP and improve sleep health of the couple. METHODS: We are conducting a two-arm, parallel group, single blind, randomized controlled pilot/feasibility trial to compare our novel couples-based sleep health intervention (We-PAP) to an information control group (IC). We-PAP is based on a transdiagnostic model and uses a dyadic approach including increasing effective partner support, communication skills, and couple-level goal-setting. We-PAP involves 3 sessions and delivered via telehealth in weekly sessions. The IC includes standardized patient educational materials. Both groups receive the usual follow-up with their medical team. The study involves assessments at pre-treatment, post-intervention (approximately 1 month after starting PAP and completing We-PAP sessions or IC) and 3 months after starting PAP. Our main outcomes are feasibility and acceptability ratings. Secondary outcomes include comparing We-PAP to IC for PAP adherence, sleep quality (self-report and objective) and cognitive measures. DISCUSSION: We-PAP is the first couples-based transdiagnostic sleep health intervention for patients with OSA and their partners. Results of this study will be used to inform the design of a subsequent fully powered clinical trial. If successful, this intervention could significantly advance current clinical practice in the treatment of OSA and sleep health more comprehensively in older adults. Moreover, this intervention may be useful for improving sleep in other aging populations with multiple sleep and other health problems, including patients with chronic illnesses or those at risk for Alzheimer's disease and their caregivers. TRIAL REGISTRATION: NCT04759157 . Date of registration: February 8, 2021. URL of trial registry record.
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Background: Despite the prevalence of motor symptoms in mild cognitive impairment (MCI) and Alzheimer's disease (AD), their underlying neural mechanisms have not been thoroughly studied. Objective: This review summarizes the neural underpinnings of motor deficits in MCI and AD. Methods: We searched PubMed up until August of 2021 and identified 37 articles on neuroimaging of motor function in MCI and AD. Study bias was evaluated based on sample size, availability of control samples, and definition of the study population in terms of diagnosis. Results: The majority of studies investigated gait, showing that slower gait was associated with smaller hippocampal volume and prefrontal deactivation. Less prefrontal activation was also observed during cognitive-motor dual tasking, while more activation in cerebellar, cingulate, cuneal, somatosensory, and fusiform brain regions was observed when performing a hand squeezing task. Excessive subcortical white matter lesions in AD were associated with more signs of parkinsonism, poorer performance during a cognitive and motor dual task, and poorer functional mobility. Gait and cognitive dual-tasking was furthermore associated with cortical thickness of temporal lobe regions. Most non-gait motor measures were only reported in one study in relation to neural measures. Conclusion: Cross-sectional designs, lack of control groups, mixing amnestic- and non-amnestic MCI, disregard of sex differences, and small sample sizes limited the interpretation of several studies, which needs to be addressed in future research to progress the field.