Age-related differences in ventral striatal and default mode network function during reciprocated trust.

Social relationships change across the lifespan as social networks narrow and motivational priorities shift to the present. Interestingly, aging is also associated with changes in executive function, including decision-making abilities, but it remains unclear how age-related changes in both domains interact to impact financial decisions involving other people. To study this problem, we recruited 50 human participants (Nyounger = 26, ages 18-34; Nolder = 24, ages 63-80) to play an economic trust game as the investor with three partners (friend, stranger, and computer) who played the role of investee. Investors underwent functional magnetic resonance imaging (fMRI) during the trust game while investees were seated outside of the scanner. Building on our previous work with younger adults showing both enhanced striatal responses and altered default-mode network (DMN) connectivity as a function of social closeness during reciprocated trust, we predicted that these relations would exhibit age-related differences. We found that striatal responses to reciprocated trust from friends relative to strangers and computers were blunted in older adults relative to younger adults, thus supporting our primary pre-registered hypothesis regarding social closeness. We also found that older adults exhibited enhanced DMN connectivity with the temporoparietal junction (TPJ) during reciprocated trust from friends compared to computers while younger adults exhibited the opposite pattern. Taken together, these results advance our understanding of age-related differences in sensitivity to social closeness in the context of trusting others.

Grit and successful aging in older adults.

OBJECTIVES: Grit is a noncognitive trait that has been shown to increase monotonically throughout adulthood and predict late-life cognitive performance. Less is known about the relation between grit and successful aging in older adults. METHOD: Participants over 55-years-old (N = 185) completed a series of self-report surveys assessing demographics, grit (Short Grit Scale; Grit-S), physical and emotional functioning (Medical Outcomes Study Short Form Health Survey; SF-36), and changes in cognitive functioning (Everyday Cognition; ECog). Principal component analysis of the Grit-S was conducted, and then Pearson product moment correlations and multiple linear regressions were used to assess the relations between grit, age, and measures of successful aging. RESULTS: Grit showed no association with age, even after controlling for education. Grit total score was positively associated with a variety of successful aging variables (SF-36; physical, emotional, and social functioning, energy, general health; all p's <.001). Component analysis of the Grit-S showed a two-component solution representing Consistency and Perseverance. Both components predicted SF-36 measures of energy, general health, and emotional function (SF-36), but only Consistency predicted cognitive decline (ECog) and SF-36 measures of physical health and pain. CONCLUSION: Grit is stable throughout older adulthood and may serve as a protective factor that promotes active adaptation to the developmental challenges of aging. Consistency of interests appears to play an adaptive role in all facets of successful aging, including stability of cognitive functioning, while perseverance of effort may have a more circumscribed positive effect on physical and emotional well-being in older adults.

A person-centered framework for designing music-based therapeutic studies in dementia: current barriers and a path forward.

Objectives: Music-based interventions have received growing attention to improve quality of life for people diagnosed with dementia. Results of randomized controlled trials and meta-analytic reviews to date, however, reveal a lack of conclusive evidence for or against the effectiveness of such interventions. Herein, we critically review the basic assumptions and methodological issues ingrained in the cultures of research and care as they relate to evaluating music-based treatments for people with dementia, and propose a shift in the methodology by which music interventions are empirically evaluated.Method: We begin by reviewing existing barriers to achieving clarity on the effectiveness of music interventions, and we highlight methodological and sociocultural constraints that have limited our ability to reach concrete conclusions in research studies to-date. We then consider several key factors that have demonstrated relevance in matching people to specific music-based interventions. Based on these key factors, we developed a person-centered framework integrating elements from precision-medicine methodology to guide intervention studies.Results: Our organizing framework systematically integrates the following factors to inform the design of intervention studies: 1) person-centered goals and desired outcomes; 2) differences among individuals in clinical, cognitive, and historical attributes; and 3) the context of intervention and access to resources.Conclusion: Integration of the proposed framework into empirical investigations of music interventions for people living with dementia will inform precise and tailored interventions that will bring clarity to this growing body of research. Another aim of this framework is to foster a more humane, person-centered approach to our culture of care.

Remind Me To Remember: A pilot study of a novel smartphone reminder application for older adults with dementia and mild cognitive impairment.

The SmartPrompt is a smartphone-based reminder application informed by a neuropsychological model of functional disability. This laboratory-based pilot study examined the SmartPrompt feasibility, efficacy, and subjective usability using a within-participant, counterbalanced, cross-over design. Ten participants (M age = 80.3 + 8.2; M education = 15.7 + 2.5; 60% female) with mild cognitive impairment or mild dementia completed the Remember to Drink Test, which required preparing a glass of water at four predetermined times, in a SmartPrompt (SP) and Unprompted condition (UP). Written cues and a clock were available in both conditions; however, in the SP, the smartphone presented auditory alarms and visual reminders to obtain the water at specified times and required photo logging. In a separate session, caregivers were trained and tested on configuring the SmartPrompt. Overall, caregivers and participants learned to effectively use the SmartPrompt. Caregivers achieved near-perfect scores on the configuration quiz and responded well to training. Participants completed significantly more Remember to Drink tasks in the SP (93%) than UP (56%); checking the cues/clock decreased by 87% in the SP. Usability ratings were excellent among caregivers and fair among participants. Results indicate that the SmartPrompt holds promise for reducing functional disability in older adults with cognitive difficulties in at-home contexts.

Cerebral Hypoxia: Its Role in Age-Related Chronic and Acute Cognitive Dysfunction.

Postoperative cognitive dysfunction (POCD) has been reported with widely varying frequency but appears to be strongly associated with aging. Outside of the surgical arena, chronic and acute cerebral hypoxia may exist as a result of respiratory, cardiovascular, or anemic conditions. Hypoxia has been extensively implicated in cognitive impairment. Furthermore, disease states associated with hypoxia both accompany and progress with aging. Perioperative cerebral hypoxia is likely underdiagnosed, and its contribution to POCD is underappreciated. Herein, we discuss the various disease processes and forms in which hypoxia may contribute to POCD. Furthermore, we outline hypoxia-related mechanisms, such as hypoxia-inducible factor activation, cerebral ischemia, cerebrovascular reserve, excitotoxicity, and neuroinflammation, which may contribute to cognitive impairment and how these mechanisms interact with aging. Finally, we discuss opportunities to prevent and manage POCD related to hypoxia.

Informant Reporting in Mild Cognitive Impairment: Sources of Discrepancy on the Functional Activities Questionnaire.

OBJECTIVE: Relative to dementia, little is known about informant bias in mild cognitive impairment (MCI). We investigated the influence of informant demographic and relational characteristics on reports of everyday functioning using the Functional Activities Questionnaire (FAQ). METHOD: Four thousand two hundred eighty-four MCI participants and their informants from the National Alzheimer's Coordinating Center Uniform Data Set were included. Informants were stratified according to cohabitation, relationship, visit frequency, race/ethnicity, education, and sex. Informant-rated Mean FAQ score was compared across these groups using univariate general linear model analyses and post hoc tests. Interactions were tested between informant variables. The predictive contribution of informant variables to FAQ score was explored using hierarchical linear regression. Analyses covaried for participant cognition using a cognitive composite score, and for participant age, sex, and depression. RESULTS: After controlling for participant cognition, depression, age, and sex, informant-rated FAQ scores varied significantly across all informant variables (p's < .005, ηp2's ≤ .033) except sex and visit frequency. FAQ scores were higher (more impaired) among informants who cohabitate with the participant, among paid caregivers, spouses, and adult children, and among informants with higher levels of education. Scores were lowest (less impaired) among Black/African American informants as compared to all other racial/ethnic groups. CONCLUSIONS: Demographic and relational characteristics of informants influence the perception and reporting of instrumental activities of daily living in adults with MCI. As everyday functioning is crucial for differential diagnosis and treatment outcome measurement, it is important to be aware of sources of informant report discrepancies.

The Everyday Compensation (EComp) Questionnaire: Construct Validity and Associations with Diagnosis and Longitudinal Change in Cognition and Everyday Function in Older Adults.

OBJECTIVE: The Everyday Compensation scale (EComp) is an informant-rated questionnaire designed to measure cognitively based compensatory strategies that support both everyday memory and executive function in the context of completing instrumental activities of daily living (IADLs). Although previous findings provided early support for the usefulness of the initial version of EComp, the current paper further describes the development, refinement, and validation of EComp as a new assessment tool of compensation for IADLs. METHOD: Confirmatory factor analysis (CFA) was used to examine its factor structure. Convergent and predictive validity was evaluated by examining the relationship between EComp and markers of disease, including diagnosis, cognitive change, and trajectories of functional abilities. RESULTS: CFA supported a general compensation factor after accounting for variance attributable to IADL domain-specific engagement. The clinical groups differed in compensatory strategy use, with those with dementia using significantly fewer compensatory strategies as compared to individuals with normal cognition or mild cognitive impairment. Greater levels of compensation were related to better cognitive functions (memory and executive function) and functional abilities, as well as slower rates of cognitive and functional decline over time. Importantly, higher levels of compensation were associated with less functional difficulties and subsequently slower rate of functional decline independent of the level of cognitive impairment. CONCLUSIONS: Engagement in compensatory strategies among older adults has important implications for prolonging functional independence, even in those with declining cognitive functioning. Results suggest that the revised EComp is likely to be useful in measuring cognitively based compensation in older adults.

Self-perceived Difficulties in Everyday Function Precede Cognitive Decline among Older Adults in the ACTIVE Study.

OBJECTIVES: Careful characterization of how functional decline co-evolves with cognitive decline in older adults has yet to be well described. Most models of neurodegenerative disease postulate that cognitive decline predates and potentially leads to declines in everyday functional abilities; however, there is mounting evidence that subtle decline in instrumental activities of daily living (IADLs) may be detectable in older individuals who are still cognitively normal. METHODS: The present study examines how the relationship between change in cognition and change in IADLs are best characterized among older adults who participated in the ACTIVE trial. Neuropsychological and IADL data were analyzed for 2802 older adults who were cognitively normal at study baseline and followed for up to 10 years. RESULTS: Findings demonstrate that subtle, self-perceived difficulties in performing IADLs preceded and predicted subsequent declines on cognitive tests of memory, reasoning, and speed of processing. CONCLUSIONS: Findings are consistent with a growing body of literature suggesting that subjective changes in everyday abilities can be associated with more precipitous decline on objective cognitive measures and the development of mild cognitive impairment and dementia. (JINS, 2018, 24, 104-112).

The ACTIVE conceptual framework as a structural equation model.

Background/Study Context: Conceptual frameworks are analytic models at a high level of abstraction. Their operationalization can inform randomized trial design and sample size considerations. METHODS: The Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) conceptual framework was empirically tested using structural equation modeling (N=2,802). ACTIVE was guided by a conceptual framework for cognitive training in which proximal cognitive abilities (memory, inductive reasoning, speed of processing) mediate treatment-related improvement in primary outcomes (everyday problem-solving, difficulty with activities of daily living, everyday speed, driving difficulty), which in turn lead to improved secondary outcomes (health-related quality of life, health service utilization, mobility). Measurement models for each proximal, primary, and secondary outcome were developed and tested using baseline data. Each construct was then combined in one model to evaluate fit (RMSEA, CFI, normalized residuals of each indicator). To expand the conceptual model and potentially inform future trials, evidence of modification of structural model parameters was evaluated by age, years of education, sex, race, and self-rated health status. RESULTS: Preconceived measurement models for memory, reasoning, speed of processing, everyday problem-solving, instrumental activities of daily living (IADL) difficulty, everyday speed, driving difficulty, and health-related quality of life each fit well to the data (all RMSEA < .05; all CFI > .95). Fit of the full model was excellent (RMSEA = .038; CFI = .924). In contrast with previous findings from ACTIVE regarding who benefits from training, interaction testing revealed associations between proximal abilities and primary outcomes are stronger on average by nonwhite race, worse health, older age, and less education (p < .005). CONCLUSIONS: Empirical data confirm the hypothesized ACTIVE conceptual model. Findings suggest that the types of people who show intervention effects on cognitive performance potentially may be different from those with the greatest chance of transfer to real-world activities.

Specific amino acids in HIV-1 Vpr are significantly associated with differences in patient neurocognitive status.

Even in the era of combination antiretroviral therapies used to combat human immunodeficiency virus type 1 (HIV-1) infection, up to 50 % of well-suppressed HIV-1-infected patients are still diagnosed with mild neurological deficits referred to as HIV-associated neurocognitive disorders (HAND). The multifactorial nature of HAND likely involves the HIV-1 accessory protein viral protein R (Vpr) as an agent of neuropathogenesis. To investigate the effect of naturally occurring variations in Vpr on HAND in well-suppressed HIV-1-infected patients, bioinformatic analyses were used to correlate peripheral blood-derived Vpr sequences with patient neurocognitive performance, as measured by comprehensive neuropsychological assessment and the resulting Global Deficit Score (GDS). Our studies revealed unique associations between GDS and the presence of specific amino acid changes in peripheral blood-derived Vpr sequences [neuropsychological impairment Vpr (niVpr) variants]. Amino acids N41 and A55 in the Vpr sequence were associated with more pronounced neurocognitive deficits (higher GDS). In contrast, amino acids I37 and S41 were connected to measurably lower GDS. All niVpr variants were also detected in DNA isolated from HIV-1-infected brain tissues. The implication of these results is that niVpr variants alter the genesis and/or progression of HAND through differences in Vpr-mediated effects in the peripheral blood and/or the brain.

Heterogeneity of Neuropsychological Impairment in HIV Infection: Contributions from Mild Cognitive Impairment.

Despite longstanding acknowledgement of the heterogeneity of HIV-associated neurocognitive disorders (HAND), existing HAND diagnostic methods classify according to the degree of impairment, without regard to the pattern of neuropsychological strengths and weaknesses. Research in mild cognitive impairment (MCI) has demonstrated that classifying individuals into subtypes by both their level and pattern of impairment, using either conventional or statistical methods, has etiologic and prognostic utility. Methods for characterizing the heterogeneity of MCI provide a framework that can be applied to other disorders and may be useful in clarifying some of the current challenges in the study of HAND. A small number of studies have applied these methods to examine the heterogeneity of neurocognitive function among individuals with HIV. Most have supported the existence of multiple subtypes of neurocognitive impairment, with some evidence for distinct clinicodemographic features of these subtypes, but a number of gaps exist. Following a review of diagnostic methods and challenges in the study of HAND, we summarize the literature regarding conventional and empirical subtypes of MCI and HAND and identify directions for future research regarding neurocognitive heterogeneity in HIV infection.

Pathogenesis and Risk Factors for Cerebral Infarct After Surgical Aortic Valve Replacement.

BACKGROUND AND PURPOSE: Stroke is a potentially devastating complication of cardiac surgery. Identifying predictors of radiographic infarct may lead to improved stroke prevention for surgical patients. METHODS: We reviewed 129 postoperative brain magnetic resonance imagings from a prospective study of patients undergoing surgical aortic valve replacement. Acute infarcts were classified as watershed or embolic using prespecified criteria. RESULTS: Acute infarct on magnetic resonance imaging was seen in 79 of 129 patients (61%), and interrater reliability for stroke pathogenesis was high (κ=0.93). Embolic infarcts only were identified in 60 patients (46%), watershed only in 2 (2%), and both in 17 (13%). In multivariable logistic regression, embolic infarct was associated with aortic arch atheroma (odds ratio [OR], 3.4; 95% confidence interval [CI], 1.0-12.0; P=0.055), old subcortical infarcts (OR, 5.5; 95% CI, 1.1-26.6; P=0.04), no history of percutaneous transluminal coronary angioplasty or coronary artery bypass graft (OR, 4.0; 95% CI, 1.2-13.7; P=0.03), and higher aortic valve gradient (OR, 1.3 per 5 mm Hg; 95% CI, 1.09-1.6; P=0.004). Watershed infarct was associated with internal carotid artery stenosis ≥70% (OR, 11.7; 95% CI, 1.8-76.8; P=0.01) and increased left ventricular ejection fraction (OR, 1.6 per 5% increase; 95% CI, 1.08-2.4; P=0.02). CONCLUSIONS: The principal mechanism of acute cerebral infarction after aortic valve replacement is embolism. There are distinct factors associated with watershed and embolic infarct, some of which may be modifiable.

Stroke after aortic valve surgery: results from a prospective cohort.

BACKGROUND: The incidence and impact of clinical stroke and silent radiographic cerebral infarction complicating open surgical aortic valve replacement (AVR) are poorly characterized. METHODS AND RESULTS: We performed a prospective cohort study of subjects ≥65 years of age who were undergoing AVR for calcific aortic stenosis. Subjects were evaluated by neurologists preoperatively and postoperatively and underwent postoperative magnetic resonance imaging. Over a 4-year period, 196 subjects were enrolled at 2 sites (mean age, 75.8±6.2 years; 36% women; 6% nonwhite). Clinical strokes were detected in 17%, transient ischemic attack in 2%, and in-hospital mortality was 5%. The frequency of stroke in the Society for Thoracic Surgery database in this cohort was 7%. Most strokes were mild; the median National Institutes of Health Stroke Scale was 3 (interquartile range, 1-9). Clinical stroke was associated with increased length of stay (median, 12 versus 10 days; P=0.02). Moderate or severe stroke (National Institutes of Health Stroke Scale ≥10) occurred in 8 (4%) and was strongly associated with in-hospital mortality (38% versus 4%; P=0.005). Of the 109 stroke-free subjects with postoperative magnetic resonance imaging, silent infarct was identified in 59 (54%). Silent infarct was not associated with in-hospital mortality or increased length of stay. CONCLUSIONS: Clinical stroke after AVR was more common than reported previously, more than double for this same cohort in the Society for Thoracic Surgery database, and silent cerebral infarctions were detected in more than half of the patients undergoing AVR. Clinical stroke complicating AVR is associated with increased length of stay and mortality.

The Potential Utility of Eye Movements in the Detection and Characterization of Everyday Functional Difficulties in Mild Cognitive Impairment.

Mild cognitive impairment (MCI) refers to the intermediate period between the typical cognitive decline of normal aging and more severe decline associated with dementia, and it is associated with greater risk for progression to dementia. Research has suggested that functional abilities are compromised in MCI, but the degree of impairment and underlying mechanisms remain poorly understood. The development of sensitive measures to assess subtle functional decline poses a major challenge for characterizing functional limitations in MCI. Eye-tracking methodology has been used to describe visual processes in everyday, naturalistic action among healthy older adults as well as several case studies of severely impaired individuals, and it has successfully differentiated healthy older adults from those with MCI on specific visual tasks. These studies highlight the promise of eye-tracking technology as a method to characterize subtle functional decline in MCI. However, to date no studies have examined visual behaviors during completion of naturalistic tasks in MCI. This review describes the current understanding of functional ability in MCI, summarizes findings of eye-tracking studies in healthy individuals, severe impairment, and MCI, and presents future research directions to aid with early identification and prevention of functional decline in disorders of aging.

Environmental Adaptations Improve Everyday Action in Schizophrenia.

Cognitive functioning, particularly executive functioning, is a strong predictor of functional outcomes in people with schizophrenia. Cognitive remediation has been shown to improve specific cognitive processes, but adjunctive interventions are required for meaningful gains in adaptive functioning, particularly in people with chronic illness. This study examined whether (and how) environmental adaptations, used without training, may circumvent cognitive difficulties and facilitate everyday task performance in individuals with chronic schizophrenia. Forty-two individuals with chronic schizophrenia/schizoaffective disorder were administered cognitive measures and two versions of the Naturalistic Action Test (NAT)-a standard version (ST-NAT), and a user-centered version (UC-NAT) that incorporated environmental adaptations designed to facilitate task performance. The NAT conditions were counterbalanced across participants. Analyses compared performance between the NAT versions and examined the cognitive correlates of each NAT condition. Individuals with schizophrenia made fewer errors on the UC-NAT as compared to the ST-NAT; this between-group difference was significant for all error types. Compared to the ST-NAT, the UC-NAT performance was not significantly associated with an executive function measure of planning. Environmental adaptations may be implemented without extensive training to improve everyday action in individuals with chronic schizophrenia. Environmental adaptations that reduce planning demands may be most effective in this population.

Hypoxia and inflammation in children with sickle cell disease: implications for hippocampal functioning and episodic memory.

Children with sickle cell disease (SCD) suffer from systemic processes (e.g., chronic anemia, recurrent hypoxic-ischemic events, chronic inflammation) that have been associated with neurocognitive impairment in a range of clinical populations, but which have been largely understudied in relation to specific domains of cognitive functioning in children with SCD. This review focuses on episodic memory, as the hippocampus may be especially vulnerable to the systemic processes associated with SCD. The first part of the paper outlines the pathophysiology of SCD and briefly reviews the extant literature on academic and cognitive functioning in children with SCD, emphasizing the dearth of research on episodic memory. Next, the complex systemic processes of hypoxia and inflammation associated with SCD are reviewed, along with research that has associated these processes with hippocampal damage and memory impairment. The paper concludes with suggestions for future research that are informed, in part, by the literature on developmental amnesia.

Commissions and omissions are dissociable aspects of everyday action impairment in schizophrenia.

Prior research using performance-based assessment of functional impairment has informed a novel neuropsychological model of everyday action impairment in dementia in which omission errors (i.e., failure to complete task steps) dissociate from commission errors (i.e., inaccurate performance of task steps) and have unique neuropsychological correlates. However, this model has not been tested in other populations. The present study examined whether this model extends to schizophrenia. Fifty-four individuals with schizophrenia or schizoaffective disorder were administered a neuropsychological protocol and the Naturalistic Action Test (NAT), a performance-based measure of everyday action. A principal component analysis (PCA) was performed to examine the construct(s) comprising everyday action impairment, and correlations between the resultant component(s) and neuropsychological tests were examined. Results showed that omissions and a subset of commissions were distinct components of everyday action. However, results did not support unique associations between these components and specific neuropsychological measures. These findings extend the omission-commission model to schizophrenia and may have important implications for efficient assessment and effective rehabilitation of functional impairment, such as the potential efficacy of targeted interventions for the rehabilitation of omission and commission deficits in everyday functioning. Larger studies with prospective designs are needed to replicate the present preliminary findings.

Preliminary validation of the Virtual Kitchen Challenge as an objective and sensitive measure of everyday function associated with cerebrovascular disease.

Preliminary validity of a computer-based test of everyday function (Virtual Kitchen Challenge [VKC]) was examined against brain-imaging markers of cerebrovascular disease and in contrast to conventional neuropsychological and self-report measures. Twenty community-dwelling older adults (n = 6 mild cognitive impairment) performed simulated breakfast and lunch tasks using a computer touchscreen (VKC). Automated measures (completion time, proportion time off screen, etc.) were computed during training and test conditions. White matter hyperintensity (WMH) volumes from brain magnetic resonance imaging and conventional measures of cognition and function also were obtained. VKC completion time and proportion time off screen improved significantly from training to test and were significantly associated with WMH volume (r > 0.573). VKC measures and WMH were not significantly correlated with conventional cognitive or self-report measures. The VKC holds promise as a valid measure of subtle functional difficulties in older adults that is sensitive to change and cerebrovascular pathology, highlighting its potential for clinical trials. Highlights: Virtual Kitchen Challenge (VKC) scores showed significant improvement from training to test conditions.VKC scores (completion time and proportion of time off screen) were associated with a neuroimaging biomarker of brain health (white matter hyperintensities).

Social reward and nonsocial reward processing across the adult lifespan: An interim multi-echo fMRI and diffusion dataset.

Social relationships change across the lifespan as social networks narrow and motivational priorities shift. These changes may affect, or reflect, differences in how older adults make decisions related to processing social and non-social rewards. While we have shown initial evidence that older adults have a blunted response to some features of social reward, further work in larger samples is needed to replicate our results and probe the extent to which age-related differences translate to real world consequences, such as financial exploitation. To address this gap, we are conducting a 5-year study funded by the National Institute on Aging (NIH R01-AG067011). Over the course of the funding period (2021-2026), this study seeks to: 1) characterize neural responses to social rewards across adulthood; 2) relate those responses to risk for financial exploitation and sociodemographic factors tied to risk; and 3) examine changes in risk for financial exploitation over time in healthy and vulnerable groups of older adults. This paper describes the preliminary release of data for the larger study. Adults (N = 114; 40 male / 70 female / 4 other or non-binary; 21-80 years of age M = 42.78, SD = 17.13) were recruited from the community to undergo multi-echo fMRI while completing tasks that measure brain function during social reward and decision making. Tasks probe neural response to social reward (e.g., peer vs. monetary feedback) and social context and closeness (e.g., sharing a monetary reward with a friend compared to a stranger). Neural response to social decision making is probed via economic trust and ultimatum games. Functional data are complimented by a T1 weighted anatomical scan and multi-shell diffusion-weighted imaging (DWI) to enable tractography and assess neurite orientation dispersion and density. Overall, this dataset has extensive potential for re-use, including leveraging multimodal neuroimaging data, within subject measures of fMRI data from different tasks - data features that are rarely seen in an adult lifespan dataset. Finally, the functional data will allow for developmentally sensitive cross-sectional analyses of differences in brain response to nuanced differences in reward contexts and outcomes (e.g., monetary vs. social; sharing winnings with a friend vs. stranger; stranger vs. computer).

Olfaction and apathy in Alzheimer's disease, mild cognitive impairment, and healthy older adults.

OBJECTIVES: Apathy is a prevalent neuropsychiatric manifestation in individuals with Alzheimer's disease (AD) that is associated with decreased social functioning and increased caregiver burden. Olfactory deficits are also commonly observed in AD, and prior work has indicated a link between increased apathy and olfactory dysfunction in individuals with Parkinson's disease. Here, we examined odor identification performance in patients with probable AD (n = 172), individuals with mild cognitive impairment (MCI; n = 112), and neurologically and psychiatrically healthy older adults (n = 132) and its relation to apathy, depression, and overall psychopathology. METHOD: Participants were administered the Sniffin' Sticks odor identification test and measures assessing severity of apathy, depression, and overall neuropsychiatric symptomatology. RESULTS: Consistent with previous research, AD and MCI patients were significantly worse at identifying odors than healthy older adults. Additionally, a sex by diagnosis interaction was observed. AD patients had significantly higher levels of apathy relative to MCI and control participants. Of note, across the entire sample odor identification deficits were correlated with level of apathy at the level of p < 0.01, but not with depression or neuropsychiatric symptom severity, when controlling for Mini-Mental State Examination (MMSE) score. CONCLUSION: Collectively, these data suggest that olfactory disturbance and apathy in AD may result from the progression of disease pathology in shared neural substrates.