Locus coeruleus integrity is related to an exploitation-based decision-making bias in older adulthood.

Optimal decision-making balances exploration for new information against exploitation of known rewards, a process mediated by the locus coeruleus and its norepinephrine projections. We predicted that an exploitation-bias that emerges in older adulthood would be associated with lower microstructural integrity of the locus coeruleus. Leveraging in vivo histological methods from quantitative MRI-magnetic transfer saturation-we provide evidence that older age is associated with lower locus coeruleus integrity. Critically, we demonstrate that an exploitation bias in older adulthood, assessed with a foraging task, is sensitive and specific to lower locus coeruleus integrity. Because the locus coeruleus is uniquely vulnerable to Alzheimer's disease pathology, our findings suggest that aging, and a presymptomatic trajectory of Alzheimer's related decline, may fundamentally alter decision-making abilities in later life.

Iron Deposition and Distribution Across the Hippocampus Is Associated with Pattern Separation and Pattern Completion in Older Adults at Risk for Alzheimer's Disease.

Elevated iron deposition in the brain has been observed in older adult humans and persons with Alzheimer's disease (AD), and has been associated with lower cognitive performance. We investigated the impact of iron deposition, and its topographical distribution across hippocampal subfields and segments (anterior, posterior) measured along its longitudinal axis, on episodic memory in a sample of cognitively unimpaired older adults at elevated familial risk for AD (N = 172, 120 females, 52 males; mean age = 68.8 ± 5.4 years). MRI-based quantitative susceptibility maps were acquired to derive estimates of hippocampal iron deposition. The Mnemonic Similarity Task was used to measure pattern separation and pattern completion, two hippocampally mediated episodic memory processes. Greater hippocampal iron load was associated with lower pattern separation and higher pattern completion scores, both indicators of poorer episodic memory. Examination of iron levels within hippocampal subfields across its long axis revealed topographic specificity. Among the subfields and segments investigated here, iron deposition in the posterior hippocampal CA1 was the most robustly and negatively associated with the fidelity memory representations. This association remained after controlling for hippocampal volume and was observed in the context of normal performance on standard neuropsychological memory measures. These findings reveal that the impact of iron load on episodic memory performance is not uniform across the hippocampus. Both iron deposition levels as well as its spatial distribution, must be taken into account when examining the relationship between hippocampal iron and episodic memory in older adults at elevated risk for AD.

Precision Mapping of the Default Network Reveals Common and Distinct (Inter)activity for Autobiographical Memory and Theory of Mind.

The default network is widely implicated as a common neural substrate for self-generated thought, such as remembering one's past (autobiographical memory) and imagining the thoughts and feelings of others (theory of mind). Findings that the default network comprises subnetworks of regions - some commonly and some distinctly involved across processes - suggest that one's own experiences inform their understanding of others. With the advent of precision fMRI methods, however, it is unclear if this shared substrate is observed instead due to traditional group analysis methods. We investigated this possibility using a novel combination of methodological strategies. Twenty-three participants underwent multi-echo resting-state and task fMRI. We used their resting-state scans to conduct cortical parcellation sensitive to individual variation but preserving our ability to conduct group analysis. Using multivariate analyses, we assessed the functional activation and connectivity profiles of default network regions while participants engaged in autobiographical memory, theory of mind, or a sensorimotor control condition. Across the default network, we observed stronger activity associated with both autobiographical memory and theory of mind compared to the control condition. Nonetheless, we also observed that some regions showed preferential activity to either experimental condition, in line with past work. The connectivity results similarly indicated shared and distinct functional profiles. Our results support that autobiographical memory and theory of mind - two theoretically important and widely-studied domains of social cognition - evoke common and distinct aspects of the default network even when ensuring high fidelity to individual-specific characteristics.

Age differences in the functional architecture of the human brain.

The intrinsic functional organization of the brain changes into older adulthood. Age differences are observed at multiple spatial scales, from global reductions in modularity and segregation of distributed brain systems, to network-specific patterns of dedifferentiation. Whether dedifferentiation reflects an inevitable, global shift in brain function with age, circumscribed, experience-dependent changes, or both, is uncertain. We employed a multimethod strategy to interrogate dedifferentiation at multiple spatial scales. Multi-echo (ME) resting-state fMRI was collected in younger (n = 181) and older (n = 120) healthy adults. Cortical parcellation sensitive to individual variation was implemented for precision functional mapping of each participant while preserving group-level parcel and network labels. ME-fMRI processing and gradient mapping identified global and macroscale network differences. Multivariate functional connectivity methods tested for microscale, edge-level differences. Older adults had lower BOLD signal dimensionality, consistent with global network dedifferentiation. Gradients were largely age-invariant. Edge-level analyses revealed discrete, network-specific dedifferentiation patterns in older adults. Visual and somatosensory regions were more integrated within the functional connectome; default and frontoparietal control network regions showed greater connectivity; and the dorsal attention network was more integrated with heteromodal regions. These findings highlight the importance of multiscale, multimethod approaches to characterize the architecture of functional brain aging.

Aging relates to a disproportionately weaker functional architecture of brain networks during rest and task states.

Functional connectivity - the co-activation of brain regions - forms the basis of the brain's functional architecture. Often measured during resting-state (i.e., in a task-free setting), patterns of functional connectivity within and between brain networks change with age. These patterns are of interest to aging researchers because age differences in resting-state connectivity relate to older adults' relative cognitive declines. Less is known about age differences in large-scale brain networks during directed tasks. Recent work in younger adults has shown that patterns of functional connectivity are highly correlated between rest and task states. Whether this finding extends to older adults remains largely unexplored. To this end, we assessed younger and older adults' functional connectivity across the whole brain using fMRI while participants underwent resting-state or completed directed tasks (e.g., a reasoning judgement task). Resting-state and task functional connectivity were less strongly correlated in older as compared to younger adults. This age-dependent difference could be attributed to significantly lower consistency in network organization between rest and task states among older adults. Older adults had less distinct or segregated networks during resting-state. This more diffuse pattern of organization was exacerbated during directed tasks. Finally, the default mode network, often implicated in neurocognitive aging, contributed strongly to this pattern. These findings establish that age differences in functional connectivity are state-dependent, providing greater insight into the mechanisms by which aging may lead to cognitive declines.

Psychological distance reduces the effect of internalized stigma on mental health treatment decisions.

Although stigma is a major barrier to treatment for those with mental health concerns, it is poorly understood when stigma is more or less influential in mental health treatment decisions. In the current work, we examined whether psychological distance - the removal of an event from direct experience - reduced the influence of internalized stigma on willingness to seek treatment. Specifically, we tested the hypothesis that psychological distance versus proximity (e.g., seeking treatment in three months vs. in two days, respectively) decreases the negative influence of stigma on willingness to seek treatment. We focused on a population for whom mental health treatment decisions are personally-relevant: individuals who had previously sought mental health treatment. Experiment 1 showed that the extent to which these individuals internalized (i.e., personally endorsed) stigma about mental illness predicted lower intentions to make an appointment with a mental health care provider for themselves (but not another person). Experiment 2 replicated this result using a different measure of psychological distance (temporal distance) and extended this finding to behavior (time spent reading mental health resources). Overall, this research demonstrated that internalized stigma disrupts mental health treatment-seeking intentions and behaviors when they are psychologically proximal, but not when they are distant. Potential applications of these results are discussed.

Age differences in specific neural connections within the Default Mode Network underlie theory of mind.

Theory of mind (i.e., the ability to infer others' mental states) - a fundamental social cognitive ability - declines with increasing age. Prior investigations have focused on identifying task-evoked differences in neural activation that underlie these performance declines. However, these declines could also be related to dysregulation of the baseline, or 'intrinsic', functional connectivity of the brain. If so, age differences in intrinsic connectivity may provide novel insight into the mechanisms that contribute to poorer theory of mind in older adults. To examine this possibility, we assessed younger and older adults' theory of mind while they underwent task-based fMRI, as well as the intrinsic functional connectivity measured during resting-state within the (task-defined) theory of mind network. Older adults exhibited poorer theory of mind behavioral performance and weaker intrinsic connectivity within this network compared to younger adults. Intrinsic connectivity between the right temporoparietal junction and the right temporal pole mediated age differences in theory of mind. Specifically, older adults had weaker intrinsic connectivity between right temporoparietal junction and right temporal pole that explained their poorer theory of mind behavioral performance. These findings broaden our understanding of aging and social cognition and reveal more specific mechanisms of how aging impacts theory of mind.

Can Ureaplasma diversum be transmitted from donor to recipient through the embryo? Two case reports outlining U. diversum losses in bovine embryo pregnancies.

Two bovine embryo recovery results are outlined from different herds. Both cases involve significant late gestational loss from embryos relating back to a single donor. Ureaplasma diversum was confirmed in 3 of 4 cases submitted for postmortem examination. Natural infection originating from the donor and transmitted to the recipient has not previously been documented.

Peut-on transmettre Ureaplasma diversumdu donneur au récipiendaire par l'embryon? Deux rapports de cas présentant des pertes associées à U. diversumlors de gestations d'embryons bovins. Deux résultats de récupération d'embryons bovins provenant de différents troupeaux sont présentés. Les deux cas portent sur la perte gestationnelle considérablement tardive d'embryons provenant d'un seul donneur. Ureaplasma diversum a été confirmé dans 3/4 des cas soumis à l'examen post mortem. Une infection naturelle provenant du donneur transmise au récipiendaire n'a pas été documentée antérieurement.(Traduit par Isabelle Vallières).

Neuromodulatory subcortical nucleus integrity is associated with white matter microstructure, tauopathy and APOE status.

The neuromodulatory subcortical nuclei within the isodendritic core (IdC) are the earliest sites of tauopathy in Alzheimer's disease (AD). They project broadly throughout the brain's white matter. We investigated the relationship between IdC microstructure and whole-brain white matter microstructure to better understand early neuropathological changes in AD. Using multiparametric quantitative magnetic resonance imaging we observed two covariance patterns between IdC and white matter microstructure in 133 cognitively unimpaired older adults (age 67.9 ± 5.3 years) with familial risk for AD. IdC integrity related to 1) whole-brain neurite density, and 2) neurite orientation dispersion in white matter tracts known to be affected early in AD. Pattern 2 was associated with CSF concentration of phosphorylated-tau, indicating AD specificity. Apolipoprotein-E4 carriers expressed both patterns more strongly than non-carriers. IdC microstructure variation is reflected in white matter, particularly in AD-affected tracts, highlighting an early mechanism of pathological development.

Perceiver and target partisanship shift facial trustworthiness effects on likability.

The affective polarization characteristic of the United States' political climate contributes to pervasive intergroup tension. This tension polarizes basic aspects of person perception, such as face impressions. For instance, face impressions are polarized by partisanship disclosure such that people form positive and negative impressions of, respectively, shared and opposing partisan faces. How partisanship interacts with other facial cues affecting impressions remains unclear. Building on work showing that facial trustworthiness, a core dimension of face perception, is especially salient for ingroup members, we reasoned that shared and opposing partisanship may also affect the relation between facial trustworthiness characteristics and subsequent likability impressions. A stronger positive relation emerged for shared versus opposing partisan faces across more conservative and liberal perceivers (Experiments 1 and 2). Exploratory analyses showed that this difference links to perceived partisan threat (Experiment 1) and that experimentally manipulating inter-party threat strengthened opposing partisan derogation and shared partisan enhancement patterns (Experiment 2). These findings suggest that partisanship extends from affecting overall face impressions of partisans to affecting the relation between a core dimension of face perception and subsequent impressions. These findings highlight the prevalence of partisanship effects in basic aspects of person perception and have implications for intergroup behavior.

Disclosing political partisanship polarizes first impressions of faces.

Americans' increasing levels of ideological polarization contribute to pervasive intergroup tensions based on political partisanship. Cues to partisanship may affect even the most basic aspects of perception. First impressions of faces constitute a widely-studied basic aspect of person perception relating to intergroup tensions. To understand the relation between face impressions and political polarization, two experiments were designed to test whether disclosing political partisanship affected face impressions based on perceivers' political ideology. Disclosed partisanship more strongly affected people's face impressions than actual, undisclosed, categories (Experiment 1). In a replication and extension, disclosed shared and opposing partisanship also engendered, respectively, positive and negative changes in face impressions (Experiment 2). Partisan disclosure effects on face impressions were paralleled by the extent of people's partisan threat perceptions (Experiments 1 and 2). These findings suggest that partisan biases appear in basic aspects of person perception and may emerge concomitant with perceived partisan threat.

Age differences in neural activity related to mentalizing during person perception.

Mentalizing, or thinking about others' mental states, shapes social interactions. Older adults (OA) have reduced mentalizing capacities reflected by lower medial prefrontal cortex (mPFC) activation. The current study assessed if OA' lower mPFC activation reflects less spontaneous mentalizing during person perception. Younger adults (YA) and OA viewed ingroup White and outgroup Black and Asian faces and completed a mentalizing task during fMRI. Afterward, they completed a task in which they inferred mental states from faces. Using an mPFC region defined by the mentalizing task, OA had lower activity than YA during person perception. OA' mPFC activity toward faces positively related to their mentalizing outside the scanner. The extent of OA' lower mPFC activation during person perception may depend on their actual detection of mental states in faces. Further, YA', but not OA', mPFC activity distinguished between outgroups. OA' lower mentalizing-related mPFC activity may reduce their ability to individuate outgroup members.

A stronger relationship between reward responsivity and trustworthiness evaluations emerges in healthy aging.

Older adults (OA) evaluate faces to be more trustworthy than do younger adults (YA), yet the processes supporting these more positive evaluations are unclear. This study identified neural mechanisms spontaneously engaged during face perception that differentially relate to OA' and YA' later trustworthiness evaluations. We examined two mechanisms: salience (reflected by amygdala activation) and reward (reflected by caudate activation) - both of which are implicated in evaluating trustworthiness. We emphasized the salience and reward value of specific faces by having OA and YA evaluate ingroup male White and outgroup Black and Asian faces. Participants perceived faces during fMRI and made trustworthiness evaluations after the scan. OA rated White and Black faces as more trustworthy than YA. OA had a stronger positive relationship between caudate activity and trustworthiness than YA when perceiving ingroup, but not outgroup, faces. Ingroup cues might intensify how trustworthiness is rewarding to OA, potentially reinforcing their overall positivity.

Evaluation of neighborhood deprivation and store characteristics in relation to tobacco retail outlet sales violations.

INTRODUCTION: Regulations of the sale of tobacco products to minors have been effective at reducing adolescent tobacco use overall. However, these efforts may not be uniformly enforced in all areas, creating uneven protection against adolescent smoking. Knowledge regarding factors associated with tobacco retail outlet (TRO) violations could help inform better enforcement strategies. METHODS: In this study, we used Bayesian index regression models to determine if tobacco sales to minors violations across Virginia (2012-2021) were related to store characteristics and neighborhood deprivation and identify geographic areas at significantly elevated risk for violations after adjusting for these factors. RESULTS: Results show that there were multiple factors associated with a higher likelihood of tobacco sales violations. Store type was an important factor, as grocery stores and pharmacies had significantly lowered likelihood of violations compared with convenience stores. Being located near another TRO was significantly associated with increased risk of sales to a minor. Neighborhood deprivation was also positively associated with TRO sales violations. Further, there were statistically higher likelihood of sales violations occurring in specific areas (e.g., southwest and southeast) of the state that were not explained by neighborhood deprivation and store attributes. CONCLUSIONS: Together, results highlight the need to better understand where and why TRO sales violations are occurring in order to improve efforts aimed at monitoring and remediating TRO sales violations.

Effects of executive ability on bias and ingroup perceptions in aging.

Prior work on aging and prejudice has identified that declining executive ability underlies older adults' (OA') increased anti-outgroup bias. The current work, however, suggests that there may also be a motivational reason. Here, we explored the possibility that for OA with relatively lower executive ability, anti-outgroup bias may serve an ironic purpose of maximizing a fundamental social goal: maintaining ingroup positivity. OA are more motivated than young adults (YA) to maximize positivity in everyday life. This process, however, can be cognitively effortful. We tested the novel predictions that (a) OA' executive ability positively predicts their evaluations of ingroup members and (b) OA might preserve positive ingroup perceptions through anti-outgroup bias if they have lower executive ability. The present work tested these predictions using a timely example of an outgroup: Muslims. Study 1 verified that non-Muslim YA and OA identified with non-Muslims (vs. Muslims) as an ingroup. Study 2 then had 3 key findings. First, we replicated work showing a negative relationship between OA' executive ability and their anti-outgroup bias by showing a negative relationship with their anti-Muslim bias. Second, OA' higher executive ability related to their having more positive perceptions of ingroup non-Muslims. Finally, OA with lower executive ability had higher ingroup positivity by having higher anti-Muslim bias. These findings suggest that when OA lack the executive ability to directly maintain a motivational goal of being positive about themselves and their ingroups, they maintain positivity at the expense of others. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Neighborhood Disadvantage and Tobacco Retail Outlet and Vape Shop Outlet Rates.

Neighborhood-level socioeconomic variables, such as the proportion of minority and low-income residents, have been associated with a greater density of tobacco retail outlets (TROs), though less is known about the degree to which these neighborhood indicators are related to vape shop outlet (VSO) density. Many studies of TROs and neighborhood characteristics include only a small set of variables and also fail to take into account the correlation among these variables. Using a carefully curated database of all TROs and VSOs in Virginia (2016-2018), we developed a Bayesian model to estimate a neighborhood disadvantage index and examine its association with rates of outlets across census tracts while also accounting for correlations among variables. Models included 12 census tract variables from the American Community Survey. Results showed that increasing neighborhood disadvantage was associated with a 63% and 64% increase in TRO and VSO risk, respectively. Important variables associated with TRO rates included % renter occupied housing, inverse median gross rent, inverse median monthly housing costs, inverse median monthly housing costs, and % vacant housing units. Important variables associated with VSO rates were % renter occupied housing and % Hispanic population. There were several spatial clusters of significantly elevated risk for TROs and VSOs in western and eastern Virginia.

Culture Impacts the Neural Response to Perceiving Outgroups Among Black and White Faces.

Outgroup members (e.g., individuals whose racial identity differs from perceivers') are stigmatized in Eastern and Western cultures. However, it remains an open question how specific cultural influences affect stigmatization. In this study, we assessed whether cultural learning (i.e., social information acquired from the people in one's environment) associated with Chinese individuals' relocation to the United States differentiated the response to multiple outgroups. Two types of cultural learning predict diverging responses to outgroups - awareness of stereotypes about different racial outgroups is associated with increased negative affect and cognitive control toward the stereotyped outgroup. Conversely, intergroup contact attenuates those responses, and does so to a greater extent for individuals from Western cultures. As Chinese-Americans would have had more opportunities to have contact with both White and Black individuals (relative to the Chinese participants), we explored their responses to outgroups as well. Because the neural regions associated with stereotyping and intergroup contact have been well-characterized, we used neuroimaging to disentangle these possibilities. Eighteen White American, 18 Chinese-American, and 17 Chinese participants - who had relocated to the United States less than 1 year prior - viewed images of Black and White individuals while undergoing functional magnetic resonance imaging (fMRI). Participants also completed measures of awareness of cultural stereotypes in the United States about Black and White individuals, implicit bias, and experiences with White and Black individuals. Behaviorally, White American and Chinese-American participants had more intergroup contact with either race than did Chinese participants, but there was no effect of participant group on stereotype knowledge or implicit bias. When viewing faces of White (as compared to Black) individuals while undergoing fMRI, White American (relative to Chinese) participants had attenuated activation in regions of the brain associated with cognitive control, including the right dorsolateral prefrontal cortex, dorsal striatum, and ventrolateral prefrontal cortex. Chinese-Americans' neural response to either race did not differ from White American or Chinese participants. Taken together, outgroup biases seemed to emerge in a culturally-dependent way based on variability in intergroup contact, but not necessarily awareness of stereotypes.

Recalling and Intending to Enact Health Recommendations: Optimal Number of Prescribed Behaviors in Multibehavior Messages.

Two experiments investigated the effects of the number of health recommendations (e.g., quit smoking; relax for a day) contained in a health-promotion message on recommendation recall and intentions to enact the recommendations. We hypothesized that if recommendations are stored individually, a higher number of presented recommendations will increase the number of recalled recommendations. As the number of recommendations increases, however, recipients are likely to summarize more recommendations as part of a single, more general theme (or header), resulting in a decrease in the proportion of recalled recommendations. Two experiments (N = 193 and N = 266) found that the total number of recalled recommendations increased and the proportion of recalled recommendations decreased with the number of presented recommendations. Experiment 2 replicated the findings with the number and the proportion of intended behaviors. The implications of these findings for future behavioral health interventions are discussed.

The female athlete syndrome. Anorexia nervosa--reflections on a personal journey.

Anorexia nervosa has one of the highest mortality rates of any mental illness. This devastating illness and related eating disorders may have long-term effects on bone health. Young women who are high-achieving students and competitive athletes are at increased risk for these disorders, which may go unrecognized in the early stages. My daughter and I share our respective reflections of her insidious descent into the dark world of anorexia nervosa and her journey back to us.

Hypoglycemia prevention via pump attenuation and red-yellow-green "traffic" lights using continuous glucose monitoring and insulin pump data.

BACKGROUND: Hypoglycemia has been identified as a primary barrier to optimal management of diabetes. This observation, in conjunction with the introduction of continuous glucose monitoring (CGM) devices, has set the stage for achieving tight glycemic control with systems that adjust the insulin pump settings based on measured glucose concentrations. Because system safety and system reliability are key considerations, there is a need for algorithms that reduce the risk of hypoglycemia in closed-loop, open-loop, and advisory-mode systems. More specifically, the algorithm presented here is formulated as a component of the independent safety system module proposed in the modular control-to-range architecture. METHODS: We developed two algorithms for attenuating insulin pump injections, which we refer to as Brakes and Power Brakes: Brakes is a pump attenuation function computed using CGM information only, while Power Brakes is an attenuation function in which a metabolic state observer with insulin input is used in addition to CGM information to inform the level of pump attenuation. These algorithms modulate the insulin pump delivery so that the insulin injection rate is dramatically reduced when the risk of hypoglycemia is high. Additionally, we combined these algorithms with an alert system that indicates a level of hypoglycemic risk to the user. RESULTS: We demonstrated the effectiveness of Brakes and Power Brakes in reducing the incidence of hypoglycemia in two simulated scenarios: an elevated basal rate scenario and a scenario in which a bolus is delivered for a meal that is skipped. For these scenarios, the incidence of hypoglycemia using Power Brakes was reduced by 88 and 94%, respectively, where we defined hypoglycemia based on the American Diabetes Association guidelines for defining and reporting as 70 mg/dl. In the elevated basal rate scenario, no rebounds above 180 mg/dl (the desired upper limit of the control-to-range protocol) following hypoglycemia were shown to occur. We demonstrated the way the hypoglycemia alert system can trigger the intake of carbohydrates to reduce the incidence of hypoglycemia by 98%. CONCLUSIONS: This article offers, for the first time, a method for smoothly reducing insulin delivery rate to prevent hypoglycemia in individuals with type 1 diabetes mellitus based on a mathematically formal assessment of hypoglycemic risk. In silico, we demonstrate the way this method can prevent hypoglycemia while avoiding hyperglycemia rebounds that exceed 180 mg/dl. In conjunction with the pump attenuation algorithms, this article also proposes a system for alerting an individual of their hypoglycemic risk that contains three "levels" of alerts in the form of a traffic light. This alert system can be used in an advisory mode setting to alert the user to take action when hypoglycemia is imminent ("red" light) or in a closed-loop setting where initiation of rescue action begins when the red light alert is triggered.