Detecting cognitive decline in high-functioning older adults: The relationship between subjective cognitive concerns, frequency of high neuropsychological test scores, and the frontoparietal control network.

OBJECTIVE: Neuropsychologists have difficulty detecting cognitive decline in high-functioning older adults because greater neurological change must occur before cognitive performances are low enough to indicate decline or impairment. For high-functioning older adults, early neurological changes may correspond with subjective cognitive concerns and an absence of high scores. This study compared high-functioning older adults with and without subjective cognitive concerns, hypothesizing those with cognitive concerns would have fewer high scores on neuropsychological testing and lower frontoparietal network volume, thickness, and connectivity. METHOD: Participants had high estimated premorbid functioning (e.g., estimated intelligence ≥75th percentile or college-educated) and were divided based on subjective cognitive concerns. Participants with cognitive concerns (n = 35; 74.0 ± 9.6 years old, 62.9% female, 94.3% White) and without cognitive concerns (n = 33; 71.2 ± 7.1 years old, 75.8% female, 100% White) completed a neuropsychological battery of memory and executive function tests and underwent structural and resting-state magnetic resonance imaging, calculating frontoparietal network volume, thickness, and connectivity. RESULTS: Participants with and without cognitive concerns had comparable numbers of low test scores (≤16th percentile), p = .103, d = .40. Participants with cognitive concerns had fewer high scores (≥75th percentile), p = .004, d = .71, and lower mean frontoparietal network volumes (left: p = .004, d = .74; right: p = .011, d = .66) and cortical thickness (left: p = .010, d = .66; right: p = .033, d = .54), but did not differ in network connectivity. CONCLUSIONS: Among high-functioning older adults, subjective cognitive decline may correspond with an absence of high scores on neuropsychological testing and underlying changes in the frontoparietal network that would not be detected by a traditional focus on low cognitive test scores.

Implementation and evaluation of a community-based mindful walking randomized controlled trial to sustain cognitive health in older African Americans at risk for dementia.

BACKGROUND: With an increasing proportion of older adults and the associated risk of Alzheimer's Disease and Related Dementias (ADRD) around the globe, there is an urgent need to engage in ADRD risk reduction efforts. African American (AA) older adults in the U.S. are disproportionally impacted by ADRD compared to other races and ethnicities. Mindful walking integrates two potentially protective factors of ADRD by elevating mindfulness and physical activity (i.e., walking), resulting in a synergistic behavioral strategy that is feasible and safe for older adults. However, the efficacy of applying this intervention for cognitive health outcomes has not been evaluated using experimental designs. METHODS: This paper documents the goal and protocol of a community-based, mindful walking randomized controlled trial to examine the short- and longer-term efficacy on cognitive and other health-related outcomes in ADRD at-risk AA older adults. The study outcomes include various brain health determinants, including cognitive function, quality of life, psychological well-being, physical activity, mindfulness, sleep, and overall health status. In addition, the estimated costs of program implementation are also collected throughout the study period. This study will recruit 114 older adults (ages 60+ years) with elevated ADRD risk from the Midlands region of South Carolina. Older adults are randomly assigned to participate in 24 sessions of outdoor mindful walking over three months or a delayed mindful walking group (n=57 in each group). Participants in both groups follow identical measurement protocols at baseline, after 12 weeks, after 18 weeks, and after 24 weeks from baseline. The outcome measures are administered in the lab and in everyday settings. Costs per participant are calculated using micro-costing methods. The eliciting participant costs for mindful walking engagement with expected results are reported using the payer and the societal perspectives. DISCUSSION: This study will generate evidence regarding the efficacy of mindful walking on sustaining cognitive health in vulnerable older adults. The results can inform future large-scale effectiveness trials to support our study findings. If successful, this mindful walking program can be scaled up as a low-cost and viable lifestyle strategy to promote healthy cognitive aging in diverse older adult populations, including those at greatest risk. TRIAL REGISTRATION: ClinicalTrials.gov number NCT06085196 (retrospectively registered on 10/08/2023).

Documenting Compliance and Symptom Reactivity for Ambulatory Assessment Methodology Following Concussion in Adolescents and Young Adults: Feasibility of the Mobile Neurocognitive Health (MNCH) Project.

OBJECTIVE: Evaluate compliance, symptom reactivity, and acceptability/experience ratings for an ecological momentary assessment (EMA) protocol involving ultra-brief ambulatory cognitive assessments in adolescent and young adult patients with concussion. SETTING: Outpatient concussion clinic. PARTICIPANTS: 116 patients aged 13 to 25 years with concussion. DESIGN: Prospective research design was used to examine compliance, symptom reactivity, and acceptability/experience for the Mobile Neurocognitive Health Project (MNCH); an EMA study of environmental exposures, symptoms, objective cognitive functioning, and symptom reactivity involving 4, daily EMA surveys (7:30 am, 10:30 am, 3:00 pm, 8:00 pm) for a period of 7 days following concussion. Overall compliance rates, symptom reactivity scores, and participant acceptability/experience ratings were described. A series of non-parametric Friedman Tests with post-hoc Wilcoxon signed-rank tests were used to examine differences in compliance and reactivity related to time of day and over the course of the protocol (first 3 days [Early Week] vs last 4 days [Late Week]). MAIN MEASURES: Compliance rates, symptom reactivity scores, participant experience/acceptability. RESULTS: Overall median compliance was 71%, and there were significantly fewer 7:30 am surveys completed compared to the 10:30 am (Z = -4.88,P ≤ .001), 3:00 pm (Z = -4.13,P ≤ .001), and 8:00 pm (Z = -4.68, P ≤ .001) surveys. Compliance for Early Week surveys were significantly higher than Late Week (Z = -2.16,P = .009). The median symptom reactivity score was 34.39 out of 100 and was significantly higher for Early Week compared to Late Week (Z = -4.59,P ≤ .001). Ninety-nine percent (89/90) of the sample agreed that the app was easy to use, and 18% (16/90) indicated that the app interfered with their daily life. CONCLUSION: Adolescents and young adults with concussion were compliant with the MNCH EMA protocol. Symptom reactivity to the protocol was low and the majority of participants reported that the app and protocol were acceptable. These findings support further investigation into applications of EMA for use in concussion studies.

Sometimes you just can't: within-person variation in working memory capacity moderates negative affect reactivity to stressor exposure.

The executive hypothesis of self-regulation places cognitive information processing at the center of self-regulatory success/failure. While the hypothesis is well supported by cross-sectional studies, no study has tested its primary prediction, that temporary lapses in executive control underlie moments of self-regulatory failure. Here, we conducted a naturalistic experiment investigating whether short-term variation in executive control is associated with momentary self-regulatory outcomes, indicated by negative affect reactivity to everyday stressors. We assessed working memory capacity (WMC) through ultra-brief, ambulatory assessments on smart phones five times per day in a 7-day ecological momentary assessment (EMA) study involving college-aged adults. We found that participants exhibited more negative affect reactivity to stressor exposures during moments when they exhibited lower than usual WMC. Contrary to previous findings, we found no between-person association between WMC and average stress reactivity. We interpret these findings as reflecting the role of executive control in determining one's effective capacity to self-regulate.

Cognitive Control Moderates the Health Benefits of Trait Self-Regulation in Young Adults.

Separate lines of epidemiological research suggest that individuals with high trait self-regulation (e.g. conscientious individuals) and individuals with higher cognitive ability (e.g. executive control/intelligence) each tend to enjoy superior health and well-being outcomes. However, it remains largely unexplored whether these personological and cognitive contributions to physical health are shared, independent, or interdependent. In the current study, we examined associations between trait self-regulation, cognitive control, self-reported physical health, and subjective well-being. A domain-general model revealed little shared variance between trait self-regulation and cognitive control but revealed significant unique relationships between each predictor and physical health. Results of a latent moderation analysis suggested that cognitive control moderated the contribution of self-regulation to health but not subjective well-being. This moderation effect was characterized by a strengthened relationship between trait self-regulation and health with decreases in cognitive control. Together, our results suggest that self-regulation and cognitive control may independently contribute to health outcomes in young adults and that self-regulation may be increasingly important for individuals lower in cognitive control.

Dynamic range of frontoparietal functional modulation is associated with working memory capacity limitations in older adults.

Older adults tend to over-activate regions throughout frontoparietal cortices and exhibit a reduced range of functional modulation during WM task performance compared to younger adults. While recent evidence suggests that reduced functional modulation is associated with poorer task performance, it remains unclear whether reduced range of modulation is indicative of general WM capacity-limitations. In the current study, we examined whether the range of functional modulation observed over multiple levels of WM task difficulty (N-Back) predicts in-scanner task performance and out-of-scanner psychometric estimates of WM capacity. Within our sample (60-77years of age), age was negatively associated with frontoparietal modulation range. Individuals with greater modulation range exhibited more accurate N-Back performance. In addition, despite a lack of significant relationships between N-Back and complex span task performance, range of frontoparietal modulation during the N-Back significantly predicted domain-general estimates of WM capacity. Consistent with previous cross-sectional findings, older individuals with less modulation range exhibited greater activation at the lowest level of task difficulty but less activation at the highest levels of task difficulty. Our results are largely consistent with existing theories of neurocognitive aging (e.g. CRUNCH) but focus attention on dynamic range of functional modulation asa novel marker of WM capacity-limitations in older adults.

Ventral fronto-parietal contributions to the disruption of visual working memory storage.

The ability to maintain information in visual working memory (VWM) in the presence of ongoing visual input allows for flexible goal-directed behavior. Previous evidence suggests that categorical overlap between visual distractors and the contents of VWM is associated with both the degree to which distractors disrupt VWM performance and activation among fronto-parietal regions of cortex. While within-category distractors have been shown to elicit a greater response in ventral fronto-parietal regions, to date, no study has linked distractor-evoked response of these regions to VWM performance costs. Here we examined the contributions of ventral fronto-parietal cortex to the disruption of VWM storage by manipulating memoranda-distractor similarity. Our results revealed that the degree of activation across cortex was graded in a manner suggesting that similarity between the contents of VWM and visual distractors influenced distractor processing. While abrupt visual onsets failed to engage ventral fronto-parietal regions during VWM maintenance, objects sharing categorical- (Related objects) and feature-overlap (Matched objects) with VWM elicited a significant response in the right TPJ and right AI. Of central relevance, the magnitude of activation in the right AI elicited by both types of distractor objects subsequently predicted costs to binding change detection accuracy. In addition, Related and Matched distractors differentially affected ventral-dorsal connectivity between the right AI and dorsal parietal regions, uniquely contributing to disruption of VWM storage. Together, our current results implicate activation of ventral fronto-parietal cortex in disruption of VWM storage, and disconnection between ventral frontal and dorsal parietal cortices as a mechanism to protect the contents of VWM.

Cardiorespiratory fitness modifies the relationship between myocardial function and cerebral blood flow in older adults.

A growing body of evidence indicates that cardiorespiratory fitness attenuates some age-related cerebral declines. However, little is known about the role that myocardial function plays in this relationship. Brain regions with high resting metabolic rates, such as the default mode network (DMN), may be especially vulnerable to age-related declines in myocardial functions affecting cerebral blood flow (CBF). This study explored the relationship between a measure of myocardial mechanics, global longitudinal strain (GLS), and CBF to the DMN. In addition, we explored how cardiorespiratory affects this relationship. Participants were 30 older adults between the ages of 59 and 69 (mean age=63.73years, SD=2.8). Results indicated that superior cardiorespiratory fitness and myocardial mechanics were positively associated with DMN CBF. Moreover, results of a mediation analysis revealed that the relationship between GLS and DMN CBF was accounted for by individual differences in fitness. Findings suggest that benefits of healthy heart function to brain function are modified by fitness.

Ultra-brief Assessment of Working Memory Capacity: Ambulatory Assessment Study Using Smartphones.

BACKGROUND: The development of mobile technology with substantial computing power (ie, smartphones) has enabled the adaptation of performance-based cognitive assessments to remote administration and novel intensive longitudinal study designs (eg, measurement burst designs). Although an "ambulatory" cognitive assessment paradigm may provide new research opportunities, the adaptation of conventional measures to a mobile format conducive to intensive repeated measurement involves balancing measurement precision, administration time, and procedural consistency. OBJECTIVE: Across 3 studies, we adapted "complex span" tests of working memory capacity (WMC) for ultra-brief, smartphone-based administration and examined their reliability, sufficiency, and associations with full-length, laboratory-based computerized administrations. METHODS: In a laboratory-based setting, study 1 examined associations between ultra-brief smartphone adaptations of the operation span, symmetry span, and rotation span tasks and full-length computerized versions. In study 2, we conducted a 4-day ecological momentary assessment (EMA) study (4 assessments per day), where we examined the reliability of ultra-brief, ambulatory administrations of each task. In study 3, we conducted a 7-day EMA study (5 assessments per day) involving the ultra-brief rotation span task, where we examined reliability in the absence of extensive onboarding and training. RESULTS: Measurement models in study 1 suggest that comparable estimates of latent WMC can be recovered from ultra-brief complex span task performance on smartphones. Significant correlations between the ultra-brief tasks and respective full-length versions were observed in study 1 and 2, ranging from r=0.4 to r=0.57. Results of study 2 and study 3 suggest that reliable between-person estimates of operation span, symmetry span, rotation span, and latent WMC can be obtained in 2-3 ultra-brief administrations (equivalent to <1 day of testing in an EMA study design). The results of study 3 replicated our findings, showing that reliable between-person estimates of rotation span may be obtained in as few as 2 ultra-brief administrations in the absence of extensive onboarding and training. In addition, the modification of task parameterization for study 3 improved the estimates of reliability of within-person change. CONCLUSIONS: Ultra-brief administration of complex span tasks on smartphones in a measurement burst design can generate highly reliable cross-sectional estimates of WMC. Considerations for future mobile cognitive assessment designs and parameterizations are discussed.

Multicultural Healthy Diet to Reduce Cognitive Decline & Alzheimer's Disease Risk: Study protocol for a pilot randomized controlled trial.

BACKGROUND: Emerging evidence indicates that healthy dietary patterns are associated with higher cognitive status; however, few clinical trials have explored this association in diverse middle-aged adults before the onset of cognitive decline. We use novel ambulatory methods to assess cognition in natural settings in tandem with diet recording. AIMS: We investigate whether the Multicultural Healthy Diet Study to Reduce Cognitive Decline & Alzheimer's Disease Risk, a pilot randomized controlled trial of an anti-inflammatory dietary pattern compared to usual diet, can mitigate cognitive decline and Alzheimer's Disease risk in a diverse population of 40-65 year old adults in Bronx, New York. METHODS: Primary cognitive outcomes assessed at nine months are collected in an ecological momentary assessment "measurement burst" design, over the course of participants' daily lives. These ultra-brief, ambulatory cognitive assessments examine processing speed, visuospatial working memory, short-term associative memory binding, long-term associative memory, and working memory capacity. Key secondary outcomes relate to comparing dietary intake between study arms with respect to cognitive outcomes. We assess diet with food records using the National Cancer Institute's Automated Self-Administered 24-h record and serum biomarkers. We further investigate the association of self-reported diet and dietary biomarkers with inflammatory-based biomarkers. CONCLUSION: This randomized controlled trial of diet and cognition for the first time combines novel measures of ambulatory cognitive assessment with web-based assessment of dietary intake recording. This new approach enabled the study to continue in the midst of the COVID-19 pandemic in remote format.

Dopamine D1 Agonists: First Potential Treatment for Late-Stage Parkinson's Disease.

Current pharmacotherapy has limited efficacy and/or intolerable side effects in late-stage Parkinson's disease (LsPD) patients whose daily life depends primarily on caregivers and palliative care. Clinical metrics inadequately gauge efficacy in LsPD patients. We explored if a D1/5 dopamine agonist would have efficacy in LsPD using a double-blind placebo-controlled crossover phase Ia/b study comparing the D1/5 agonist PF-06412562 to levodopa/carbidopa in six LsPD patients. Caregiver assessment was the primary efficacy measure because caregivers were with patients throughout the study, and standard clinical metrics inadequately gauge efficacy in LsPD. Assessments included standard quantitative scales of motor function (MDS-UPDRS-III), alertness (Glasgow Coma and Stanford Sleepiness Scales), and cognition (Severe Impairment and Frontal Assessment Batteries) at baseline (Day 1) and thrice daily during drug testing (Days 2-3). Clinicians and caregivers completed the clinical impression of change questionnaires, and caregivers participated in a qualitative exit interview. Blinded triangulation of quantitative and qualitative data was used to integrate findings. Neither traditional scales nor clinician impression of change detected consistent differences between treatments in the five participants who completed the study. Conversely, the overall caregiver data strongly favored PF-06412562 over levodopa in four of five patients. The most meaningful improvements converged on motor, alertness, and functional engagement. These data suggest for the first time that there can be useful pharmacological intervention in LsPD patients using D1/5 agonists and also that caregiver perspectives with mixed method analyses may overcome limitations using methods common in early-stage patients. The results encourage future clinical studies and understanding of the most efficacious signaling properties of a D1 agonist for this population.

Ambulatory Assessment in Concussion Clinical Care and Rehabilitation.

Concussion is a mild traumatic brain injury that is characterized by a wide range of physical, emotional, and cognitive symptoms as well as neurocognitive, vestibular, and ocular impairments that can negatively affect daily functioning and quality of life. Clinical consensus statements recommend a targeted, clinical profile-based approach for management and treatment. This approach requires that clinicians utilize information obtained via a clinical interview and a multi-domain assessment battery to identify clinical profile(s) (e.g., vestibular, mood/anxiety, ocular, migraine, cognitive fatigue) and prescribe a corresponding treatment/rehabilitation program. Despite this comprehensive approach, the clinical picture can be limited by the accuracy and specificity of patient reports (which often conflate timing and severity of symptomology), as well as frequency and duration of exposure to symptom exacerbating environments (e.g., busy hallways, sitting in the back seat of a car). Given that modern rehabilitation programs leverage the natural environment as a tool to promote recovery (e.g., expose-recover approach), accurate characterization of the patient clinical profile is essential to improving recovery outcomes. Ambulatory assessment methodology could greatly benefit concussion clinical care by providing a window into the symptoms and impairments experienced by patients over the course of their daily lives. Moreover, by evaluating the timing, onset, and severity of symptoms and impairments in response to changes in a patient's natural environment, ambulatory assessments can provide clinicians with a tool to confirm clinical profiles and gauge effectiveness of the rehabilitation program. In this perspective report, we review the motivations for utilizing ambulatory assessment methodology in concussion clinical care and report on data from a pilot project utilizing smart phone-based, ambulatory assessments to capture patient reports of symptom severity, environmental exposures, and performance-based assessments of cognition for 7 days following their initial evaluation.

Accounting for retest effects in cognitive testing with the Bayesian double exponential model via intensive measurement burst designs.

Monitoring early changes in cognitive performance is useful for studying cognitive aging as well as for detecting early markers of neurodegenerative diseases. Repeated evaluation of cognition via a measurement burst design can accomplish this goal. In such design participants complete brief evaluations of cognition, multiple times per day for several days, and ideally, repeat the process once or twice a year. However, long-term cognitive change in such repeated assessments can be masked by short-term within-person variability and retest learning (practice) effects. In this paper, we show how a Bayesian double exponential model can account for retest gains across measurement bursts, as well as warm-up effects within a burst, while quantifying change across bursts in peak performance. We also highlight how this approach allows for the inclusion of person-level predictors and draw intuitive inferences on cognitive change with Bayesian posterior probabilities. We use older adults' performance on cognitive tasks of processing speed and spatial working memory to demonstrate how individual differences in peak performance and change can be related to predictors of aging such as biological age and mild cognitive impairment status.

Fornix white matter microstructure differentially predicts false recollection rates in older and younger adults.

Healthy aging is accompanied by increased false remembering in addition to reduced successful remembering in older adults. Neuroimaging studies implicate age-related differences in the involvement of medial temporal lobe and fronto-parietal regions in mediating highly confident false recollection. However, no studies have directly examined the relationship between white matter microstructure and false recollection in younger and older adults. Using diffusion-weighted imaging and probabilistic tractography, we examined how white matter microstructure within tracts connecting the hippocampus and the fronto-parietal retrieval network contribute to false recollection rates in healthy younger and older adults. We found only white matter microstructure within the fornix contributed to false recollection rates, and this relationship was specific to older adults. Fornix white matter microstructure did not contribute to true recollection rate, nor did common white matter contribute to false recollection, suggesting fornix microstructure is explicitly associated with highly confident false memories in our sample of older adults. These findings underlie the importance of examining microstructural correlates associated with false recollection in younger and older adults.

Mindful walking and cognition in older adults: A proof of concept study using in-lab and ambulatory cognitive measures.

Mindfulness practice and walking have been linked individually to sustain cognition in older adults. This early-phase study aimed to establish proof-of-concept by evaluating whether an intervention that integrates light-intensity walking with mindfulness practices shows promising signs of improving cognition in older adults. Participants (N = 25, Mage = 72.4 ± 6.45) were community-dwelling older adults who engaged in a supervised mindful walking program over one month (8 sessions total, 2 sessions per week, 30-minute slow walking containing mindfulness skills). They completed performance-based and subjective ratings of cognitive measures in field before and after two mindful walking bouts using a smartphone app. They also completed in-lab performance-based and self-report cognitive measures at baseline and after the entire program. Controlling for demographics, potential covariates, and time trends, short-term improvements in perceived cognition and processing speed were observed from pre- to post-mindful walking sessions (i.e., 30 min) across multiple ambulatory cognitive measures (Cohen's ds range = 0.46-0.66). Longer-term improvements in processing speed and executive function were observed between baseline and end of the program (i.e., one month) across various performance-based cognitive measures (ds range = 0.43-1.28). No significant changes were observed for other cognitive domains. This early-phase study (Phase IIa) provides preliminary support that mindful walking activity is promising for sustaining cognition in older adults. Our promising findings form the building blocks of evidence needed to advance this intervention to a fully powered randomized controlled trial that examines program efficacy with a comparator. Favorable outcomes will inform the development of this lifestyle behavioral strategy for promoting healthy brain aging in late adulthood.

Variability in Cognitive Performance on Mobile Devices Is Sensitive to Mild Cognitive Impairment: Results From the Einstein Aging Study.

Background and Objective: Within-person variability in cognitive performance has emerged as a promising indicator of cognitive health with potential to distinguish normative and pathological cognitive aging. We use a smartphone-based digital health approach with ecological momentary assessments (EMA) to examine differences in variability in performance among older adults with mild cognitive impairment (MCI) and those who were cognitively unimpaired (CU). Method: A sample of 311 systematically recruited, community-dwelling older adults from the Einstein Aging Study (Mean age = 77.46 years, SD = 4.86, Range = 70-90; 67% Female; 45% Non-Hispanic White, 40% Non-Hispanic Black) completed neuropsychological testing, neurological assessments, and self-reported questionnaires. One hundred individuals met Jak/Bondi criteria for MCI. All participants performed mobile cognitive tests of processing speed, visual short-term memory binding, and spatial working memory on a smartphone device up to six times daily for 16 days, yielding up to 96 assessments per person. We employed heterogeneous variance multilevel models using log-linear prediction of residual variance to simultaneously assess cognitive status differences in mean performance, within-day variability, and day-to-day variability. We further tested whether these differences were robust to the influence of environmental contexts under which assessments were performed. Results: Individuals with MCI exhibited greater within-day variability than those who were CU on ambulatory assessments that measure processing speed (p < 0.001) and visual short-term memory binding (p < 0.001) performance but not spatial working memory. Cognitive status differences in day-to-day variability were present only for the measure of processing speed. Associations between cognitive status and within-day variability in performance were robust to adjustment for sociodemographic and contextual variables. Conclusion: Our smartphone-based digital health approach facilitates the ambulatory assessment of cognitive performance in older adults and the capacity to differentiate individuals with MCI from those who were CU. Results suggest variability in mobile cognitive performance is sensitive to MCI and exhibits dissociative patterns by timescale and cognitive domain. Variability in processing speed and visual short-term memory binding performance may provide specific detection of MCI. The 16-day smartphone-based EMA measurement burst offers novel opportunity to leverage digital technology to measure performance variability across frequent assessments for studying cognitive health and identifying early clinical manifestations of cognitive impairment.

Reduced prefrontal and temporal processing and recall of high "sensation value" ads.

Public service announcements (PSAs) are non-commercial broadcast ads that are an important part of televised public health campaigns. "Message sensation value" (MSV), a measure of sensory intensity of audio, visual, and content features of an ad, is an important factor in PSA impact. Some communication theories propose that higher message sensation value brings increased attention and cognitive processing, leading to higher ad impact. Others argue that the attention-intensive format could compete with ad's message for cognitive resources and result in reduced processing of PSA content and reduced overall effectiveness. Brain imaging during PSA viewing provides a quantitative surrogate measure of PSA impact and addresses questions of PSA evaluation and design not accessible with traditional subjective and epidemiological methods. We used Blood Oxygenation Level Dependent (BOLD) functional Magnetic Resonance Imaging (fMRI) and recognition memory measures to compare high and low MSV anti-tobacco PSAs and neutral videos. In a short-delay, forced-choice memory test, frames extracted from PSAs were recognized more accurately than frames extracted from the NV. Frames from the low MSV PSAs were better recognized than frames from the high MSV PSAs. The accuracy of recognition of PSA frames was positively correlated with the prefrontal and temporal, and negatively correlated with the occipital cortex activation. The low MSV PSAs were associated with greater prefrontal and temporal activation, than the high MSV PSAs. The high MSV PSAs produced greater activation primarily in the occipital cortex. These findings support the "dual processing" and "limited capacity" theories of communication that postulate a competition between ad's content and format for the viewers' cognitive resources and suggest that the "attention-grabbing" high MSV format could impede the learning and retention of an ad. These findings demonstrate the potential of using neuroimaging in the design and evaluation of mass media public health communications.

Clinically silent Alzheimer's and vascular pathologies influence brain networks supporting executive function in healthy older adults.

Aging is associated with declines in executive function. We examined how executive functional brain systems are influenced by clinically silent Alzheimer's disease (AD) pathology and cerebral white-matter hyperintensities (WMHs). Twenty-nine younger adults and 34 cognitively normal older adults completed a working memory paradigm while functional magnetic resonance imaging was performed. Older adults further underwent lumbar cerebrospinal fluid draw for the assessment of AD pathology and FLAIR imaging for the assessment of WMHs. Accurate working memory performance in both age groups was associated with high fronto-visual functional connectivity (fC). However, in older adults, higher expression of fronto-visual fC was linked with lower levels of clinically silent AD pathology. In addition, AD pathology and WMHs were each independently related to increased functional magnetic resonance imaging response in the left dorsolateral prefrontal cortex, a pattern associated with slower task performance. Our results suggest that clinically silent AD pathology is related to lower expression of a fronto-visual fC pattern supporting executive task performance. Further, our findings suggest that AD pathology and WMHs appear to be linked with ineffective increases in frontal response in CN older adults.

Polygraphy and Functional Magnetic Resonance Imaging in Lie Detection: A Controlled Blind Comparison Using the Concealed Information Test.

OBJECTIVE: Intentional deception is a common act that often has detrimental social, legal, and clinical implications. In the last decade, brain activation patterns associated with deception have been mapped with functional magnetic resonance imaging (fMRI), significantly expanding our theoretical understanding of the phenomenon. However, despite substantial criticism, polygraphy remains the only biological method of lie detection in practical use today. We conducted a blind, prospective, and controlled within-subjects study to compare the accuracy of fMRI and polygraphy in the detection of concealed information. Data were collected between July 2008 and August 2009. METHOD: Participants (N = 28) secretly wrote down a number between 3 and 8 on a slip of paper and were questioned about what number they wrote during consecutive and counterbalanced fMRI and polygraphy sessions. The Concealed Information Test (CIT) paradigm was used to evoke deceptive responses about the concealed number. Each participant's preprocessed fMRI images and 5-channel polygraph data were independently evaluated by 3 fMRI and 3 polygraph experts, who made an independent determination of the number the participant wrote down and concealed. RESULTS: Using a logistic regression, we found that fMRI experts were 24% more likely (relative risk = 1.24, P < .001) to detect the concealed number than the polygraphy experts. Incidentally, when 2 out of 3 raters in each modality agreed on a number (N = 17), the combined accuracy was 100%. CONCLUSIONS: These data justify further evaluation of fMRI as a potential alternative to polygraphy. The sequential or concurrent use of psychophysiology and neuroimaging in lie detection also deserves new consideration.

Evidence for reduced efficiency and successful compensation in older adults during task switching.

Older adults often show different functional activation patterns than younger adults in prefrontal cortex (PFC) when performing cognitive control tasks. These differences include age-related increases in PFC activation magnitude and reorganized PFC functional connectivity (fC) patterns. However, it remains unclear whether age-related alterations in brain activation patterns reflect a positive mechanism (e.g., compensatory response) or a sign of brain dysfunction (e.g., reduced efficiency). Here we used functional magnetic resonance imaging (fMRI) to compare PFC activation magnitudes and PFC connectivity patterns between younger and older adult groups during performance of a task switching paradigm. Results indicated age-related increases both in PFC activation magnitudes and in PFC fC with inferotemporal (IT) regions. However, these age-related fMRI increases were differentially associated with task performance. Whereas increased PFC activation magnitudes tended to be either unrelated to task RT or associated with poorer task performance, increased PFC-IT connectivity was associated with better task performance in older adults. Our results suggest that age-related reductions in efficiency and successful compensation can co-exist in older adults in the context of the same task.