Socioeconomic position and cardiovascular and neuroendocrine responses following cognitive challenge in old age

Cardiac psychophysiological tuning to socioaffective content is disrupted in aged rhesus monkeys (Macaca mulatta)

Aging ushers in numerous disruptions to autonomic nervous system (ANS) function. Although the effects of aging on ANS function at rest are well characterized, there is surprising variation in reports of age-related differences in ANS reactivity to psychosocial stressors, with some reports of decreases and other reports of increases in reactivity with age. The sources of variation in age-related differences are largely unknown. Nonhuman primate models of socioaffective aging may help to uncover sources of this variation as nonhuman primates share key features of human ANS structure and function and researchers have precise control over the environments in which they age. In this report, we assess how response patterns to dynamic socioaffective stimuli in the parasympathetic and sympathetic branches of rhesus monkeys (Macaca mulatta) ANS differ in aged compared to middle-aged monkeys. We find that respiratory sinus arrhythmia, a cardiac indicator of activity in the parasympathetic branch of the ANS, exhibits age-related disruptions in responding while monkeys view videos of conspecifics. This suggests that there are evolutionarily conserved mechanisms responsible for the patterns of affective aging observed in humans and that aged rhesus monkeys are a robust translational model for human affective aging.

Effort Mobilization and Healthy Aging

Healthy aging is in part dependent upon people's willingness and ability to mobilize the effort necessary to support behaviors that promote health and well-being. People may have the best information relating to health along with the best intentions to stay healthy (e.g., health-related goals), but positive outcomes will ultimately be dependent upon them actually investing the necessary effort toward using this information to achieve their goals. In addition, the influences on effort mobilization may vary as a function of physical, psychological, and social changes experienced by the individual across the life span. Building on the overall theme of this special issue, we explore the relationships between motivation, effort mobilization, and healthy aging. We begin by characterizing the relationship between motivation and effort, and identify the factors that influence effort mobilization. We then consider the factors associated specifically with aging that may influence effort mobilization (e.g., changes in cardiovascular and neural mechanisms) and, ultimately, the health and well-being of older adults. Finally, distinguishing between those influential factors that are modifiable versus intractable, we identify ways to structure situations and beliefs to optimize mobilization in support of healthy aging.

Can Reactivity of Heart Rate Variability Be a Potential Biomarker and Monitoring Tool to Promote Healthy Aging? A Systematic Review With Meta-Analyses

Background: Monitoring phasic responses of heart rate variability (HRV) in terms of HRV reactivity [i. e., the absolute change from resting state to on-task (i.e., absolute values of HRV measured during exercise)] might provide useful insights into the individual psychophysiological responses of healthy middle-aged to older adults (HOA) to cognitive and physical exercises. Objectives: To summarize the evidence of phasic HRV responses to cognitive and physical exercises, and to evaluate key moderating factors influencing these responses. Methods: A systematic review with meta-analyses was performed. Publications up to May 2020 of the databases Medline (EBSCO), Embase, Cochrane Library, CINAHL, Psycinfo, Web of Science, Scopus, and Pedro were considered. Controlled clinical trials and observational studies measuring phasic HRV responses to cognitive and/or physical exercises in HOA (≥50 years) were included. Results: The initial search identified 6,828 articles, of which 43 were included into the systematic review. Compared to resting state, vagally-mediated HRV indices were significantly reduced during all types of exercises [Hedge's g = -0.608, 95 % CI (-0.999 to -0.218), p = 0.002] indicating a significant parasympathetic withdrawal compared to rest. The key moderating variables of these responses identified included exercise intensity for physical exercises, and participant characteristics (i.e., level of cognitive functioning, physical fitness), task demands (i.e., task complexity and modality) and the individual responses to these cognitive challenges for cognitive exercises. In particular, higher task demands (task complexity and physical exercise intensity) were related to larger HRV reactivities. Better physical fitness and cognition were associated with lower HRV reactivities. Additionally, HRV reactivity appeared to be sensitive to training-induced cognitive and neural changes. Conclusion: HRV reactivity seems to be a promising biomarker for monitoring internal training load and evaluating neurobiological effects of training interventions. Further research is warranted to evaluate the potential of HRV reactivity as a monitoring parameter to guide cognitive-motor training interventions and/or as a biomarker for cognitive impairment. This may facilitate the early detection of cognitive impairment as well as allow individualized training adaptations that, in turn, support the healthy aging process by optimizing individual exercise dose and progression of cognitive-motor training.

Subjective Socioeconomic Status Matters Less When Perceived Social Support Is High: A Study of Cortisol Responses to Stress

Low objective and subjective socioeconomic status (SES) is associated with the experience of frequent stressors known to have physiological costs. We tested whether perceived social support, a key health-protective resource, buffered the association between lower subjective SES and cortisol responses to an acute stressor. Participants ( N = 115; 54.78% female; age M = 19.56) reported subjective SES and perceived support, completed a social-evaluative stressor task, and provided saliva for cortisol assessment. There was a significant interaction of subjective SES with support predicting linear change in cortisol stress responses, γ = .08, z = 2.34, p = .02. When support was low, subjective SES was strongly related to cortisol, and those who reported lower subjective SES exhibited higher cortisol during recovery than those who reported higher subjective SES. When support was high, those who reported higher and lower subjective SES exhibited similar cortisol responses. These results highlight the important protective role that supportive relationships can have when subjective SES is low.

Aging and effort expenditure: The impact of subjective perceptions of task demands

Engagement in cognitively demanding activities has a positive impact on cognitive health in older adults. Previous work, however, has suggested that the costs associated with engagement increase in later life and influence motivation. We examined how subjective perceptions of these costs varied with age and influenced task engagement. The following questions were of specific interest: (a) Are there age differences in subjective perceptions of cognitive costs? (b) What is the impact of these perceptions on engagement? We tested 39 older (ages 65-84) and 37 younger (20-42) adults on a working memory task. Systolic blood pressure responsivity (SBP-R; reflective of effort) and subjective perceptions of task difficulty were assessed. We found that age was associated with an increase in the perceptions of cognitive costs, and that these subjective perceptions had a stronger impact on older adults' engagement than on that of younger adults. More important, this impact was specific to subjective perceptions of cognitive costs. The results provide further support for the hypothesis that increased costs associated with cognitive engagement influence older adults' willingness to engage cognitive resources, and that these costs in part reflect subjective perceptions that are independent of objective task demands. (PsycINFO Database Record

The interplay of subjective social status and essentialist beliefs about cognitive aging on cortisol reactivity to challenge in older adults

Older adults are more likely than younger adults to experience stress when confronted with cognitive challenges. However, little is known about individual differences that might explain why some older adults exhibit stronger stress responses than others. We examined the interplay of two social-cognitive factors to explain older adults' cortisol reactivity: (1) subjective social status, and (2) essentialist beliefs about cognitive aging. We hypothesized that, depending on whether older adults believe that aging-related cognitive decline is inevitable versus modifiable, low subjective social status should lead to stronger or weaker cortisol reactivity. Using longitudinal data, we assessed the impact of cognitive challenges on stress reactivity in a sample of older adults (N = 389; 61-86 years). As predicted, regression analyses confirmed that 44 min after cognitively challenging tasks, older adults exhibited a significantly different cortisol reactivity depending on their subjective social status and their essentialist beliefs about cognitive aging. Specifically, older adults with low subjective social status and high essentialist beliefs showed a significantly elevated cortisol reactivity. We discuss the role of essentialist beliefs about cognitive aging to predict when and why high versus low subjective social status leads to stress responses in older adults.

Assessment of Adult Age differences in Task Engagement: The Utility of Systolic Blood Pressure

The constructs of effort and engagement are central to many theoretical frameworks associated with the study of aging. Age differences in the effort associated with effortful cognitive operations have been hypothesized to account for aging effects in ability, and shifting goals and motivation have been hypothesized to be associated with differential levels of engagement across situations in younger and older adults. Unfortunately, the assessment of effort and engagement-constructs that we view as relatively synonymous-has suffered in the field of aging due to the lack of well-validated measures. We suggest that systolic blood pressure might provide an easy and valid means for examining age differences in mental effort, and present evidence in support of its usage. Existing findings clearly support its potential utility, but further empirical and theoretical work is necessary.

Selective Engagement of Cognitive Resources: Motivational Influences on Older Adults' Cognitive Functioning

In this article, I present a framework for understanding the impact of aging-related declines in cognitive resources on functioning. I make the assumption that aging is associated with an increase in the costs of cognitive engagement, as reflected in both the effort required to achieve a specific level of task performance and the associated depletion or fatigue effects. I further argue that these costs result in older adults being increasingly selective in the engagement of cognitive resources in response to these declines. This selectivity is reflected in (a) a reduction in the intrinsic motivation to engage in cognitively demanding activities, which, in part, accounts for general reductions in engagement in such activities, and (b) greater sensitivity to the self-related implications of a given task. Both processes are adaptive if viewed in terms of resource conservation, but the former may also be maladaptive to the extent that it results in older adults restricting participation in cognitively demanding activities that could ultimately benefit cognitive health. I review supportive research and make the general case for the importance of considering motivational factors in understanding aging effects on cognitive functioning.

The association between cortisol and neighborhood disadvantage in a U.S. population-based sample of adolescents

The association between neighborhood conditions and cortisol is rarely studied in children or adolescents and has been hampered by small sample size and racial/ethnic and geographic homogeneity. Our objective was to estimate the association between neighborhood disadvantage and salivary cortisol levels in a large, geographically and racially/ethnically diverse sample of adolescents from the National Comorbidity Survey Replication Adolescent Supplement. Salivary cortisol was collected before and after an interview administered in the adolescent's home. We used a propensity score approach to match adolescents living in disadvantaged neighborhoods with those in non-disadvantaged neighborhoods to create two similar groups based on the time and day of cortisol collection as well as demographic characteristics. Adolescents living in disadvantaged neighborhoods had higher pre-interview cortisol levels and steeper rates of decline in cortisol levels over the course of the interview than similar adolescents in non-disadvantaged neighborhoods. This bolsters the evidence base suggesting that place may influence the stress response system.

Race differences in age-trends of autonomic nervous system functioning

OBJECTIVE

The objective of this study was to consider race differences in age-trends of autonomic nervous system functioning, using a national data set with a broad age range.

METHODS

Measures of baseline heart rate variability (HRV) and HRV reactivity were derived from electrocardiograph (ECG) recordings taken at rest and during cognitive stress tasks. Age-trends in HRV and HRV reactivity were compared among 204 African Americans and 833 Whites ages 34 to 83 years (M = 53.7, SD = 11.4), before and after controlling for socioeconomic status (SES).

RESULTS

For HRV-reactivity, age-trends were steeper among African Americans and lower SES participants than Whites and higher SES participants. For baseline HRV, age-trends varied by SES but not race.

DISCUSSION

Results relating to HRV-reactivity (but not baseline HRV) were consistent with hypotheses suggesting that African Americans are exposed to higher levels of stress and experience accelerated declines in health across the life span. The relevance of the findings to research on social stress and health disparities is discussed.

Neighborhood disadvantage and adolescent stress reactivity

Lower socioeconomic status (SES) is associated with higher levels of life stress, which in turn affect stress physiology. SES is related to basal cortisol and diurnal change, but it is not clear if SES is associated with cortisol reactivity to stress. To address this question, we examined the relationship between two indices of SES, parental education and concentrated neighborhood disadvantage, and the cortisol reactivity of African–American adolescents to a modified version of the Trier Social Stress Test (TSST). We found that concentrated disadvantage was associated with cortisol reactivity and this relationship was moderated by gender, such that higher concentrated disadvantage predicted higher cortisol reactivity and steeper recovery in boys but not in girls. Parental education, alone or as moderated by gender, did not predict reactivity or recovery, while neither education nor concentrated disadvantage predicted estimates of baseline cortisol. This finding is consistent with animal literature showing differential vulnerability, by gender, to the effects of adverse early experience on stress regulation and the differential effects of neighborhood disadvantage in adolescent males and females. This suggests that the mechanisms underlying SES differences in brain development and particularly reactivity to environmental stressors may vary across genders.

Heart rate recovery after cognitive challenge is preserved with age

OBJECTIVE

To investigate the effect of age on heart rate recovery (HRR) from cognitive challenge.

BACKGROUND

Aging is an independent risk factor for the development of cardiovascular disease. HRR from exercise is an established predictor of cardiac morbidity and mortality, and evidence suggests that HRR from cognitive challenge is predictive of cardiac morbidity as well. Aging is associated with delayed HRR from exercise stress, but little is known about the effect of aging on HRR from psychological stress. We tested the hypothesis that age would be related to delayed HRR from psychological stress.

METHODS

HRR post exposure to cognitive challenge (mental arithmetic and Stroop) was investigated in a sample of 436 participants aged 35 to 84 years in MIDUS II, a national study of health and well-being. HRR was measured as 1) the amount of change from the stress level; 2) time to recover; and 3) the area under the curve. The analyses were controlled for medical comorbidities and medications that influence HR, such as body mass index, smoking, sex, menopausal status, and amount of physical activity/exercise.

RESULTS

There was no effect for age on HRR as evaluated by all three recovery assessment methods.

CONCLUSIONS

Contrary to expectation and in contrast to findings concerning HRR from exercise, HRR from cognitive challenge was preserved with age. These findings require further inquiry into differential mechanism(s) underlying HRR from psychological versus exercise stress, including any role for improved emotion regulation with greater age.

Heart rate recovery predicts memory performance in older adults

The current study examined cardiovascular reactivity and recovery during memory testing in a sample of 28 younger and 28 older adults. Heart rate (HR) levels were measured before, during, and after a memory test (word list recall). Contrary to prediction, older adults did not have a blunted cardiovascular response to memory tasks compared to younger adults. Word list recall performance was predicted by both Age and an Age x HR recovery interaction. As expected, younger adults performed better on the word list task than older adults. In addition, older adults with better posttest HR recovery performed significantly better than older adults with poor posttest HR recovery, whereas HR recovery differences in younger adults were inconsequential. These relationships were not affected by subjective appraisals of anxiety and task difficulty. Overall, cardiac dysregulation, seen here as low HR recovery, represents an important, potentially modifiable, factor in memory performance in older adults. In addition to being beneficial to overall health, interventions designed to help older adults regulate their HR responses may help offset certain memory declines.

The effects of cognitive behavior therapy on depression in older patients with cardiovascular risk

This study examined the effect of a cognitive behavior therapy (CBT) therapy intervention designed to reduce depression in older patients with elevated cardiovascular disease (CVD) risk. Forty-eight depressed patients with elevated CVD were randomized to a 16-week individual CBT intervention (n = 23) or a wait-list control (WLC) group (n = 25). Pre- and post-treatment measures of depression were obtained during office visits, and measures of positive and negative affect were obtained during laboratory psychological stress testing and at five points during the day. At post-treatment, the CBT subjects were significantly less depressed than WLC subjects on the Hamilton Depression Inventory (F = 52.8, P<.001, ES = 1.85) and the Beck Depression Inventory (F = 17.1, P = <.001, ES = 0.85). Fifty-seven percent (13/23) of subjects in the CBT treatment were considered to be in remission (on the basis of a clinical interview) at post compared to only 4% (1/25) in the WLC (chi(2) = 9.0, P =.003). Treatment subjects reported significantly less stress on the Perceived Stress Scale (F = 23.2, P<.001). CBT significantly improved mean positive affect during the day (F = 12.7, P =.0001) but there were no significant differences in mean negative affect (F = 1.8, P =.19). CBT significantly reduced negative affect (F = 7.1, P =.01) during psychological stress testing but did not affect positive affect. CBT is an effective treatment for reducing depression and increasing positive affect in patients at risk for CVD, but the results vary by time of measurement and measurement setting.

Coping with competition: neuroendocrine responses and cognitive variables

Confronting another individual or group motivated by the same goal is a very frequent situation in human communities that occurs in many other species. Competitive interactions emerge as critical situations that shed light on the effects and consequences of social stress on health. But more important than the situation itself is the way it is interpreted by the subject. This "appraisal" involves cognitive processes that contribute to explaining the neuroendocrine response to these interactions, helping to understanding the vulnerability or resistance to their effects. In this review, we defend the need to study human competition within the social stress framework, while maintaining an evolutionary perspective, and taking advantage of the theoretical and methodological advances in psychology and psychophysiology in order to better understand the cognitive processes underlying the social stress response in humans.

Biology and health inequality

Intriguing parallels between civil servant and nonhuman primate hierarchies suggest that highly stratified societies foster health inequalities. Determining how social differences translate into chronic disease remains a challenge, but neuroendocrine pathways appear to play a role.

Education modulates cortisol reactivity to the Trier Social Stress Test in middle-aged adults

The present study assessed the modulating effect of education level on cortisol reactivity to the Trier Social Stress Test (TSST) in a sample of 101 middle-aged adults (22 males, 79 females) between the ages of 50 and 65. The TSST involves a public speech and mental arithmetic task in front of an audience. No previous studies have assessed whether education level can have an impact on cortisol reactivity to this psychosocial stressor. It is plausible that greater exposure to academia may impact how one perceives and responds to the demands of the speech and arithmetic task. Should education have an impact on cortisol reactivity to the TSST, future studies will be required to control for this factor in order to reduce both statistical error and false interpretations. In addition to completing the TSST, participants were administered a battery of neurocognitive tests and personality questionnaires, including a report on education level (i.e. number of years total and degree: High School, Junior College, Technical, University). Results showed that adults with post-secondary education above Junior College tended to secrete higher cortisol levels overall, as measured by total area under the curve. However, it was the group with lower educational attainment who showed a greater stress response specific to the TSST, as measured by percentage increase in cortisol from pre- to post-TSST. Analyses also found that higher educated adults performed better than their less educated peers on verbal fluency. Considering that the TSST is an oral task, it is suggested that middle-aged individuals with a lower level of education may find the TSST more stressful due to lower verbal capacity, which may lead to an increased cortisol response to the TSST when compared to individuals with a higher level of education.

Subjective social status moderates cortisol responses to social threat

Research has demonstrated a robust relationship between social status, physiology and health in humans and animals. However, perceptions of social status within a specific social group have rarely been studied in this area and may provide additional relevant information. The current investigation examines subjective perceptions of social status as a moderator of cognitive, emotional and cortisol responses to stressor tasks characterized by social-evaluative threat or its absence. As part of a larger study, 81 college students living in a residential dormitory completed a measure of their subjective perceptions of their social status within their dormitory floor. They were randomly assigned to undergo a standard performance stressor task either with or without social evaluation. It was hypothesized that individuals who perceived that they were of low status within their dorm group would show greater increases in negative self-evaluative emotions (i.e., shame) and cognitions (low social self-esteem) and greater cortisol responses to the stressor under conditions of social-evaluative threat. Subjective social status moderated cortisol responses to the social-evaluative stressor, but in a direction opposite that hypothesized. Individuals who perceived themselves to be of high status showed sizable and significant cortisol increases (both peak and recovery), while those who perceived themselves to be of low status did not mount a significant cortisol response to the stressor. Both groups showed increased negative self-evaluative responses to the tasks. A discussion of the possible health implications of the robust cortisol responses of high status individuals and the hyporesponsive cortisol reactions of low status individuals is provided.

Subjective socioeconomic position, gender and cortisol responses to waking in an elderly population

Socioeconomic inequalities in morbidity and mortality exist, but the psychobiological pathways that link social status and health are less clear. It has previously been reported that socioeconomic status is inversely associated with the magnitude of the cortisol response to awakening (CAR) in men and women of working age. In the present study, we tested whether larger cortisol responses would be present in an older retired population, and whether the CAR differed between men and women. The extent to which adherence to saliva sample timing also affects the CAR was investigated. Ninety three men and women aged 65-80 years took saliva samples on waking, and then 10, 20, 30 and 60 min after waking. Subjective social status was assessed using the 'ladder' measure devised by Adler et al. (2000). Non-compliance was defined as a reported delay of 10 min or more between waking and taking the first saliva sample. Cortisol levels on waking were significantly higher in the non-compliant individuals, and the CAR was blunted compared with that of compliant participants. With non-compliant participants eliminated from the analyses, we found that low social status was associated with a larger CAR after adjusting for gender, waist/hip ratio, body mass index, smoking, time of waking, chronic illness, prescription medication, education and financial strain. No association was found between CAR and education or financial strain. Women also had significantly larger CARs, independent of socioeconomic position. The results highlight the importance of controlling for non-compliance and are consistent with the notion that higher socioeconomic position protects against stress-related activation of psychobiological pathways which may contribute to variation in disease risk evident in old age.