Longitudinal Patterns and Predictors of Cognitive Impairment Classification Stability.

Objective: Classifications such as Cognitive Impairment, No Dementia (CIND) are thought to represent the transitory, pre-clinical phase of dementia. However, increasing research demonstrates that CIND represents a nonlinear, unstable entity that does not always lead to imminent dementia. The present study utilizes a longitudinal repeated measures design to gain a thorough understanding of CIND classification stability patterns and identify predictors of future stability.

Intraindividual Variability in Attention-Deficit/Hyperactivity Disorder: An Ex-Gaussian Approach.

Higher intraindividual variability (IIV) of response times is consistently noted in children with attention-deficit/hyperactivity disorder (ADHD). The current study investigated whether an ex-Gaussian estimate of IIV in children ages 6-13 years-old could differentiate between children with and without ADHD. Children completed a computerized go/no-go task to estimate trial-by-trial IIV and a continuous performance test (CPT) to estimate inattention and hyperactivity/impulsivity.

Premorbid personality traits as predictors for incident predementia syndromes: a multistate model approach.

Objective: Associations have been found between five-factor model (FFM) personality traits and risk of developing specific predementia syndromes such as subjective cognitive decline (SCD) and mild cognitive impairment (MCI). The aims of this study were to: 1) Compare baseline FFM traits between participants who transitioned from healthy cognition or SCD to amnestic MCI (aMCI) versus non-amnestic MCI (naMCI); and 2) Determine the relationship between FFM traits and risk of transition between predementia cognitive states.

Methods: Participants were 562 older adults from the Einstein Aging Study, 378 of which had at least one follow-up assessment.

Electrophysiological variability during tests of executive functioning: A comparison of athletes with and without concussion and sedentary control participants.

Objective: Sport participation may benefit executive functioning (EF), but EF can also be adversely affected by concussion, which can occur during sport participation. Neural variability is an emerging proxy of brain health that indexes the brain's range of possible responses to incoming stimuli (i.e.

Choral singing and dementia: Exploring musicality as embodied and relational accomplishment.

This study explored the impact of participation in Voices in Motion (ViM), an intergenerational community choir program that involved persons with dementia, care partners, and high school students in Victoria, British Columbia, Canada. Data came from interviews with 23 duets, each consisting of a person with dementia and their care partner; additionally, five focus groups with 29 students across two ViM choirs were conducted. Choir rehearsals and concerts were also observed.

Exploring the impact of community-based choral participation on cognitive function and well-being for persons with dementia: evidence from the Voices in Motion project.

Objectives: Music-based interventions are postulated to mitigate cognitive decline in individuals with dementia. However, the mechanisms underlying music-based interventions facilitate cognitive benefits remain unknown. The present study examines whether a choral intervention can modulate patterns of cognitive change in persons with dementia and whether within-person variation in affect is associated with this change.

Parameterizing Practice in a Longitudinal Measurement Burst Design to Dissociate Retest Effects From Developmental Change: Implications for Aging Neuroscience.

: In longitudinal designs, the extraneous influence of retest effects can confound and obscure estimates of developmental change. The current study provides a novel approach to independently parameterize short-term retest effects and long-term developmental change estimates by leveraging a measurement burst design and three-level multilevel modeling. We further employ these short- and long-term slopes as predictors of cognitive status at long-term follow-up assessments.

Intraindividual variability in executive and motor control tasks in children with attention deficit hyperactivity disorder.

Objective: Emerging evidence highlights intraindividual variability (IIV) during executive function (EF) tasks as a reliable endophenotype of Attention Deficit/Hyperactivity Disorder (ADHD) and as contributing to motor dysregulation and hyperactive-impulsive behaviors. This study examined the relationship between EF and motor control in children with and without ADHD.

Method: Ninety-seven children (6-13 years) completed standardized and experimental tasks of executive and motor control.

A socially-engaged lifestyle moderates the association between gait velocity and cognitive impairment.

Cognitive status has been linked to impaired gait velocity, and diminished social and physical engagement. To date, the potential moderating influence of lifestyle engagement on gait-cognitive status associations has not been systematically explored. The present investigation examines whether a socially- or physically-engaged lifestyle moderates the association between diminished gait velocity and likelihood of amnestic mild cognitive impairment (a-MCI) classification.

Longitudinal changes in response time mean and inconsistency exhibit predictive dissociations for risk of cognitive impairment.

Objective: Although mean response time (RT) is a commonly used indicator of cognitive function, trial-to-trial variability (RT inconsistency [RTI]) represents a dissociable dimension of performance arguably more sensitive for characterizing cognitive status. The present study explores whether (a) RT mean or inconsistency reflects a more dispositional characteristic of an individual, particularly with increased cognitive impairment; (b) RT mean and inconsistency exhibit comparable patterns of change across a 4-year period; and (c) these rates of change differentially predict cognitive status.

Method: A sample of 304 adults (64-92 years) at baseline completed a choice RT task weekly for 4-5 weeks, repeating this protocol and a basic neuropsychological assessment annually for 4 years.

White Matter Integrity Is Associated With Intraindividual Variability in Neuropsychological Test Performance in Healthy Older Adults.

Inconsistency of performance across neuropsychological testing instruments (dispersion) shows sensitivity to acquired injury and neurodegenerative pathology in older adults. The underlying neural correlates have remained speculative however, in spite of known white matter degradation seen in conjunction with elevated inconsistency in related operationalizations of intraindividual variability. Consistently, these operationalizations have controlled for artifactual age-related variance to increase measurement sensitivity of CNS dysfunction.

Intraindividual variability in children is related to informant ratings of attention and executive function.

: Attention and executive function (EF) deficits are ubiquitous in neurodevelopmental disorders including Attention Deficit/Hyperactivity Disorder (ADHD), as are high levels of intraindividual variability (IIV). Attention and EF are typically assessed using informant ratings and objective measures; however, discrepancies between different metrics often make it difficult to fully characterize a child's attention capabilities, and IIV has been proposed as a potentially useful discriminator. Our objective was to explore the relationship between IIV, using the residualized intraindividual standard deviation (rISD) method, and informant ratings of attention and EF in a mixed pediatric sample, to determine the potential utility of IIV for aiding attention diagnostics.

Associations Between Control Beliefs and Response Time Inconsistency in Older Adults Vary as a Function of Attentional Task Demands.

Objective: Control beliefs are established correlates of cognitive aging. Despite recent demonstrations that response time inconsistency (RTI) represents a proxy for cognitive processing efficiency, few investigations have explored links between RTI and psychosocial correlates. We examined associations among RTI and control beliefs (perceived competence and locus of control) for two choice-response time (RT) tasks varying in their attentional demands.

Decomposing the within-person and between-person sources of variation in physical activity-cognition associations for low-active older adults.

Objectives: To examine within-person and between-person sources of variation in the relationship between physical activity and cognition in older adults participating in a walking program. To explore whether demographic, health and fitness variables, and their interactions with activity, are significant predictors of cognition.

Design: Brief longitudinal burst design.

Daily Stress Processes as Contributors to and Targets for Promoting Cognitive Health in Later Life.

Objective: The aim of this study was to test the hypothesis that daily stress processes, including exposure and emotional reactivity to daily stressors, are associated with response time inconsistency (RTI), an indicator of processing efficiency and cognitive health. Furthermore, we considered daily stress-cognitive health associations at the level of individual differences and within-persons over time.

Methods: Participants were 111 older adults (mean = 80 years, range = 66-95 years) enrolled in a measurement burst study where assessments of response time-based cognitive performance, stressful experiences, and affect were administered on each of 6 days for a 2-week period.

Contrasting olfaction, vision, and audition as predictors of cognitive change and impairment in non-demented older adults.

Objective: This study examines the relative utility of a particular class of noninvasive functional biomarkers-sensory functions-for detecting those at risk of cognitive decline and impairment. Three central research objectives were examined including whether (a) olfactory function, vision, and audition exhibited significant longitudinal declines in nondemented older adults; (b) multiwave change for these sensory function indicators predicted risk of mild cognitive impairment (MCI); and (c) change within persons for each sensory measure shared dynamic time-varying associations with within-person change in cognitive functioning.

Method: A longitudinal sample (n = 408) from the Victoria Longitudinal Study was assembled.

The Ups and Downs of Cognitive Function: Neuroticism and Negative Affect Drive Performance Inconsistency.

Objectives: Response time inconsistency (RTI)-or trial-to-trial variability in speeded performance-is increasingly recognized as an indicator of transient lapses of attention, cognitive health status, and central nervous system integrity, as well as a potential early indicator of normal and pathological cognitive aging. Comparatively, little research has examined personality predictors of RTI across adulthood.

Methods: We evaluated the association between the personality trait neuroticism and RTI in a community-dwelling sample of 317 adults between the ages of 19-83 and tested for two indirect pathways through negative affect (NA) and cognitive interference (CI).

Intraindividual Variability across Neuropsychological Tests: Dispersion and Disengaged Lifestyle Increase Risk for Alzheimer's Disease.

: Increased intraindividual variability (IIV) in function has been linked to various age-related outcomes including cognitive decline and dementia. Most studies have operationalized IIV as fluctuations across trials (e.g.

The influence of social support and perceived stress on response time inconsistency.

Objectives: Lack of social support and high levels of stress represent potentially modifiable risk factors for cognitive aging. In this study we examined the relationships between these two risk factors and response time inconsistency (RTI), or trial-to-trial variability in choice response time tasks. RTI is an early indicator of declining cognitive health, and examining the influence of modifiable psychosocial risk factors on RTI is important for understanding and promoting cognitive health during adulthood and old age.

A Comprehensive Comparison of Quantifications of Intraindividual Variability in Response Times: A Measurement Burst Approach.

Objectives: To formally identify and contrast the most commonly-employed quantifications of response time inconsistency (RTI) and elucidate their utility for understanding within-person (WP) and between-person (BP) variation in cognitive function with increasing age.

Method: Using two measurement burst studies of cognitive aging, we systematically identified and computed five RTI quantifications from select disciplines to examine: (a) correlations among RTI quantifications; (b) the distribution of BP and WP variation in RTI; and (c) the comparability of RTI quantifications for predicting attention switching.

Results: Comparable patterns were observed across studies.

Mean and variability in functional brain activations differentially predict executive function in older adults: an investigation employing functional near-infrared spectroscopy.

Objective: although the preponderance of research on functional brain activity investigates mean group differences, mounting evidence suggests that variability in neural activity is beneficial for optimal central nervous system (CNS) function. Independent of mean signal estimates, recent findings have shown that neural variability diminishes with age and is positively associated with cognitive performance, underscoring its adaptive nature. The present investigation sought to employ functional near infrared spectroscopy (fNIRS) to derive two operationalizations of cerebral oxygenation, representing mean and variability [using standard deviation (SD)] in neural activity, and to specifically contrast these mean- and SD-oxyhemoglobin (HbO) estimates as predictors of cognitive function.

Health behavior changes in adolescence and young adulthood: Implications for cardiometabolic risk.

Objective: Adolescence and young adulthood produce developmentally salient and contextual challenges for health behavior choices. The present study examines how changes in physical activity, nutrition, and sleep duration before and after high school graduation influence cardiometabolic risk (CMR) in adulthood (at ages 22-29).

Method: Youth (N = 662; Time 1 ages 12-18; 48% male) were followed biannually across 10 years.