Recent life stress exposure is associated with poorer long-term memory, working memory, and self-reported memory

Prospective exploration of the role of combined internalizing symptoms in self-reported memory among older adults during the COVID-19 pandemic

OBJECTIVES

A growing literature suggests depression and anxiety increase risk of cognitive decline. However, few studies have examined their combined effects on cognition, among older adults, especially during periods of high stress.

METHOD

Based on a sample of community dwelling older adults (N = 576), we evaluated the effects of pre-pandemic anxiety and depressive symptoms, obtained in September 2018, to changes in self-reported memory (SRM) assessed 3 months into the COVID-19 pandemic.

RESULTS

In separate models, we found participants with depression scores at least 1-SD above the mean and participants with anxiety scores at least 2-SD above the mean to report a significant decline in SRM. Moderation analyses revealed those with high depressive symptoms (at or above the mean) showed a decrease in SRM regardless of anxiety. The extent to which high pre-pandemic anxiety symptoms influenced SRM is dependent on whether pre-pandemic depression was at or above the mean.

CONCLUSIONS

Pre-pandemic depression predicted a decline in SRM regardless of anxiety. Moderation analyses revealed that the extent to which anxiety symptoms influenced SRM was dependent on depression being at or above the mean. Those with high anxiety and depression are at highest risk of experiencing cognitive consequences related to stressful exposures like COVID-19.

Class I histone deacetylases inhibition reverses memory impairment induced by acute stress in mice

While chronic stress induces learning and memory impairments, acute stress may facilitate or prevent memory consolidation depending on whether it occurs during the learning event or before it, respectively. On the other hand, it has been shown that histone acetylation regulates long-term memory formation. This study aimed to evaluate the effect of two inhibitors of class I histone deacetylases (HDACs), 4-phenylbutyrate (PB) and IN14 (100 mg/kg/day, ip for 2 days), on memory performance in mice exposed to a single 15-min forced swimming stress session. Plasma corticosterone levels were determined 30 minutes after acute swim stress in one group of mice. In another experimental series, independent groups of mice were trained in one of three different memory tasks: Object recognition test, Elevated T maze, and Buried food location test. Subsequently, the hippocampi were removed to perform ELISA assays for histone deacetylase 2 (HDAC2) expression. Acute stress induced an increase in plasma corticosterone levels, as well as hippocampal HDAC2 content, along with an impaired performance in memory tests. Moreover, PB and IN14 treatment prevented memory loss in stressed mice. These findings suggest that HDAC2 is involved in acute stress-induced cognitive impairment. None of the drugs improved memory in non-stressed animals, indicating that HDACs inhibitors are not cognitive boosters, but rather potentially useful drugs for mitigating memory deficits.

Hydrocortisone Differentially Affects Reinstatement of Pain-related Responses in Patients With Chronic Back Pain and Healthy Volunteers

Despite the crucial role of effective and sustained extinction of conditioned pain-related fear in cognitive-behavioral treatment approaches for chronic pain, experimental research on extinction memory retrieval in chronic pain remains scarce. In healthy populations, extinction efficacy of fear memory is affected by stress. Therefore, we investigated the effects of oral hydrocortisone administration on the reinstatement of pain-related associations in 57 patients with non-specific chronic back pain (CBP) and 59 healthy control (HC) participants in a differential pain-related conditioning paradigm within a placebo-controlled, randomized, and double-blind design. Participants' skin conductance responses indicate hydrocortisone-induced reinstatement effects in HCs but no observable reinstatement in HCs receiving placebo treatment. Interestingly, these effects were reversed in patients with CBP, that is, reinstatement responses were only observed in the placebo and not in the hydrocortisone group. Our findings corroborate previous evidence of stress-induced effects on extinction efficacy and reinstatement of fear memory in HCs, extending them into the pain context, and call for more research to clarify the role of stress in fear extinction and return of fear phenomena possibly contributing to treatment failure in chronic pain treatment. PERSPECTIVE: Opposing effects in HCs and patients with non-specific CBP may be associated with changes in the patients' stress systems. These findings could be of relevance to optimizing psychological, extinction-based treatment approaches.

Writing about a stressful experience improves semantic clustering of memory in men, not women

Writing about negative experiences can produce multiple benefits, including improvements in mental and emotional health. However, writing about negative experiences potentially be detrimental, as reliving and reexperiencing a negative memory can be painful. Although the emotional effects of writing about negative experiences are well established, the cognitive effects are less heavily explored, and no work to date has examined how writing about a stressful experience might influence episodic memory. We addressed this issue in the present study (N = 520) by having participants encode a list of 16 words that were organised around four semantic clusters, randomly assigning participants to write about an unresolved stressful experience (n = 263) or the events of the previous day (n = 257), and assessing their memory in a free recall task. Writing about a stressful experience did not influence overall memory performance; however, the stressful writing manipulation increased semantic clustering of information within memory for men, whereas the stressful writing manipulation did not influence semantic clustering of information within memory in women. Additionally, writing with more positive sentiment improved semantic clustering and reduced serial recall. These results provide evidence for unique sex differences in writing about stressful experiences and the role of sentiment in the effects of expressive writing.

The Stress Phenotyping Framework: A multidisciplinary biobehavioral approach for assessing and therapeutically targeting maladaptive stress physiology

Although dysregulated stress biology is becoming increasingly recognized as a key driver of lifelong disparities in chronic disease, we presently have no validated biomarkers of toxic stress physiology; no biological, behavioral, or cognitive treatments specifically focused on normalizing toxic stress processes; and no agreed-upon guidelines for treating stress in the clinic or evaluating the efficacy of interventions that seek to reduce toxic stress and improve human functioning. We address these critical issues by (a) systematically describing key systems and mechanisms that are dysregulated by stress; (b) summarizing indicators, biomarkers, and instruments for assessing stress response systems; and (c) highlighting therapeutic approaches that can be used to normalize stress-related biopsychosocial functioning. We also present a novel multidisciplinary Stress Phenotyping Framework that can bring stress researchers and clinicians one step closer to realizing the goal of using precision medicine-based approaches to prevent and treat stress-associated health problems.

Molecular neurobiology of loss: a role for basolateral amygdala extracellular matrix

Psychological loss is a common experience that erodes well-being and negatively impacts quality of life. The molecular underpinnings of loss are poorly understood. Here, we investigate the mechanisms of loss using an environmental enrichment removal (ER) paradigm in male rats. The basolateral amygdala (BLA) was identified as a region of interest, demonstrating differential Fos responsivity to ER and having an established role in stress processing and adaptation. A comprehensive multi-omics investigation of the BLA, spanning multiple cohorts, platforms, and analyses, revealed alterations in microglia and the extracellular matrix (ECM). Follow-up studies indicated that ER decreased microglia size, complexity, and phagocytosis, suggesting reduced immune surveillance. Loss also substantially increased ECM coverage, specifically targeting perineuronal nets surrounding parvalbumin interneurons, suggesting decreased plasticity and increased inhibition within the BLA following loss. Behavioral analyses suggest that these molecular effects are linked to impaired BLA salience evaluation, leading to a mismatch between stimulus and reaction intensity. These loss-like behaviors could be rescued by depleting BLA ECM during the removal period, helping us understand the mechanisms underlying loss and revealing novel molecular targets to ameliorate its impact.

Evaluation of the Everyday Memory Questionnaire-Revised in a menopausal population: understanding the brain fog during menopause

OBJECTIVE

Brain fog (ie, memory complaints and concentration difficulties) is frequently reported during the menopausal transition. There is lack of standardized scales available to measure brain fog across the menopausal transition. This study aimed to evaluate the factor structure of the Everyday Memory Questionnaire-Revised (EMQ-R) and to determine the most commonly reported everyday cognitive symptoms in a menopausal population.

METHODS

Four hundred seventeen eligible women aged from 40 to 60 years (107 premenopausal, 149 perimenopausal, and 161 early postmenopausal) were recruited from the general community and were included in the analyses. Confirmatory factor analysis was conducted to test the model fit of the bifactor structure (ie, 4-item attentional subscale ranged 0-16, 7-item retrieval subscale ranged 0-28) of the 13-item EMQ-R (ranged 0-52) in a menopausal populations. Typical items in the retrieval subscale include "difficulty finding words," the attentional subscale include "difficulty following the thread of a story," and analysis of variance and multivariate analysis of covariance were used to investigate the group differences of individual items and two subscales.

RESULTS

Confirmatory factor analysis indicated the bifactor structure of the EMQ-R has a good fit in all three groups. A significant difference was identified in the mean retrieval scores (pre: 11.8, peri: 13.6, early post: 11.7) but not in the mean attentional scores (pre: 4.53, peri: 5.01, early post: 4.65).

CONCLUSIONS

The EMQ-R retrieval subscale may serve as a potential instrument to assess memory retrieval symptoms that contribute to "brain fog" in menopause. Increased memory retrieval complaints reported by the perimenopausal group suggests a transition-related memory retrieval dysfunction during menopausal transition.

The mediating role of depressive symptoms and subjective cognitive dysfunction in the relationship between stressful life events and functional disability in adult community volunteers

BACKGROUND

Stressful life events (SLE) impact psychosocial functioning. However, the psychological mechanism underlying the association between SLE and functional disability (FD) has not been fully elucidated. This study focused on whether depressive symptoms (DS) and subjective cognitive dysfunction (SCD) mediated the influence of SLE, comprising negative SLE (NSLE) and positive SLE (PSLE), on FD.

METHODS

A total of 514 adults from Tokyo, Japan, completed the self-administered questionnaires to evaluate DS, SCD, SLE, and FD. We investigated the relationships among the variables using path analysis.

RESULTS

Path analyses showed that NSLE positively affected FD directly (β = 0.253, p < .001), and indirectly via DS and SCD (β = 0.192, p < .001). PSLE negatively affected FD indirectly via DS and SCD (β = -0.068, p = .010), although PSLE did not affect FD directly (β = -0.049, p = .163).

LIMITATIONS

Causal relationships could not be determined owing to the cross-sectional design. All participants were recruited in Japan, which limits the generalization of findings to other countries.

CONCLUSIONS

DS and SCD, in this order, may partially mediate the positive effect of NSLE on FD. DS and SCD may fully mediate the negative effect of PSLE on FD. When considering the impact of SLE on FD, evaluating the mediating role of DS and SCD could be useful. Our findings may elucidate how perceived life stress affects daily functioning via depressive and cognitive symptoms. In the future, it is desirable to conduct a longitudinal study based on our results.

Does heart rate variability mediate the association between chronic stress, cardiorespiratory fitness, and working memory in young adults?

Young adulthood is a demanding development phase rendering individuals at risk for high levels of stress. While chronic stress may impair working memory maintenance, cardiorespiratory fitness is suggested to have a protective effect. Heart rate variability (HRV) contributes to this cognitive domain, but also retaliates to stress and aerobic exercise. Therefore, the present study investigated the mediating role of resting HRV on the association between chronic stress, cardiorespiratory fitness, and working memory maintenance in young healthy adults. Healthy participants (N = 115, 48% female) aged 18-35 years (M = 24.1, SD = 3.8) completed the Åstrand test on a bicycle ergometer to estimate maximal oxygen consumption [ V ̇ O 2 max $$ \dot{\mathrm{V}}{\mathrm{O}}_{2\max } $$ (ml/min/kg)]. In addition, working memory maintenance was assessed using the modified Sternberg task with low (three items) and high cognitive load (six items). Using electrocardiography, HRV was recorded and the LF/HF ratio was extracted for mediation analyses. Path analysis revealed that cardiorespiratory fitness was significantly associated with accuracy on high cognitive load trials (β = 0.19, p = 0.035), but not on trials with low cognitive load. Perceived levels of chronic stress failed to show a significant association with working memory maintenance, independently of cognitive load. The pattern of results remained unchanged after introduction of HRV as a mediator (β = 0.18, p = 0.045). In conclusion, higher cardiorespiratory fitness is associated with better maintenance of verbal information in working memory. However, this association cannot be explained by vagal influences on memory processing driven by the autonomic nervous system.

Even affective changes induced by the global health crisis are insufficient to perturb the hyper-stability of visual long-term memory

Past studies of emotion and mood on memory have mostly focused on the learning of emotional material in the laboratory or on the consequences of a punctate catastrophic event. However, the influence of a long-lasting global condition on memory and learning has not been studied. The COVID-19 pandemic unfortunately offered a unique situation to observe the effects of prolonged, negative events on human memory for visual information. One thousand online subjects were asked to remember the details of real-world photographs of objects to enable fine-grained visual discriminations from novel within-category foils. Visual memory performance was invariant across time, regardless of the infection rate in the local or national population, or the subjects’ self-reported affective state using the Positive and Negative Affect Schedule (PANAS). Thus, visual memory provides the human brain with storage that is particularly resilient to changes in emotional state, even when those changes are experienced for months longer than any imaginable laboratory procedure.

Establishing a Framework for Gathering Structural and Social Determinants of Health in Alzheimer's Disease Research Centers

Structural and social determinants of health (SSDoH) are environmental conditions in which individuals are born, live, learn, work, play, worship, and age that affect health, functioning, and quality-of-life outcomes across the life course. Growing evidence suggests that SSDoH can help to explain heterogeneity in outcomes in Alzheimer's disease and Alzheimer's disease and related dementias (AD/ADRD) research and clinical practice. The National Institute on Aging has prioritized collecting SSDoH data to elucidate disease mechanisms and aid discovery of disease-modifying treatments. However, a major nexus of AD/ADRD research, the national network of Alzheimer's Disease Research Centers (ADRCs), collects few SSDoH data. We describe a framework for feasibly gathering and modeling SSDoH data across ADRCs. We lay out key constructs, their measures, and empirical evidence for their importance in elucidating disease and prevention mechanisms. Toward a goal of translation, the framework proposes a modular structure with a core set of measures and options for adjunctive modules. We describe considerations for measuring SSDoH in existing geographically and culturally diverse research cohorts. We also outline a rationale for universal implementation of a set of SSDoH measures and juxtapose the approach with alternatives aimed at collecting SSDoH data.

Spatiotemporal patterns of pain distribution and recall accuracy: a dose-response study

OBJECTIVES

Clinical decisions rely on a patient's ability to recall and report their pain experience. Monitoring pain in real-time (momentary pain) may reduce recall errors and optimize the clinical decision-making process. Tracking momentary pain can provide insights into detailed changes in pain intensity and distribution (area and location) over time. The primary aims of this study were (i) to measure the temporal changes of pain intensity, area, and location in a dose-response fashion and (ii) to assess recall accuracy of the peak pain intensity and distribution seven days later, using a digital pain mapping application. The secondary aims were to (i) evaluate the influence of repeated momentary pain drawings on pain recall accuracy and (ii) explore the associations among momentary and recall pain with psychological variables (pain catastrophizing and perceived stress).

METHODS

Healthy participants (N=57) received a low (0.5 ml) or a high (1.0 ml) dose of hypertonic saline (5.8%) injection into the right gluteus medius muscle and, subsequently, were randomized into a non-drawing or a drawing group. The non-drawing groups reported momentary pain intensity every 30-s. Whereas the drawing groups reported momentary pain intensity and distribution on a digital body chart every 30-s. The pain intensity, area (pixels), and distribution metrics (compound area, location, radiating extent) were compared at peak pain and over time to explore dose-response differences and spatiotemporal patterns. All participants recalled the peak pain intensity and the peak (most extensive) distribution seven days later. The peak pain intensity and area recall error was calculated. Pain distribution similarity was determined using a Jaccard index which compares pain drawings representing peak distribution at baseline and recall. The relationships were explored among peak intensity and area at baseline and recall, catastrophizing, and perceived stress.

RESULTS

The pain intensity, area, distribution metrics, and the duration of pain were lower for the 0.5 mL than the 1.0 mL dose over time (p<0.05). However, the pain intensity and area were similar between doses at peak pain (p>0.05). The pain area and distribution between momentary and recall pain drawings were similar (p>0.05), as reflected in the Jaccard index. Additionally, peak pain intensity did not correlate with the peak pain area. Further, peak pain intensity, but not area, was correlated with catastrophizing (p<0.01).

CONCLUSIONS

This study showed differences in spatiotemporal patterns of pain intensity and distribution in a dose-response fashion to experimental acute low back pain. Unlike pain intensity, pain distribution and area may be less susceptible in an experimental setting. Higher intensities of momentary pain do not appear to influence the ability to recall the pain intensity or distribution in healthy participants.

IMPLICATIONS

The recall of pain distribution in experimental settings does not appear to be influenced by the intensity despite differences in the pain experience. Pain distribution may add additional value to mechanism-based studies as the distribution reports do not vary with pain catastrophizing. REC# N-20150052.

The Effects of COVID-19 Lockdown on Health and Psychosocial Functioning in Older Adults Aged 70 and Over

The COVID-19 pandemic led to a state-imposed lockdown in the UK; there are many psychosocial consequences of pandemics, with older adults potentially at an increased risk. The current study assessed psychosocial functioning in a sample of older adults in the UK with baseline data collected pre-lockdown and follow-up 12 weeks later during lockdown. Thus, allowing investigation of the effect of COVID-19 and associated lockdown on psychosocial well-being. Thirty-five older adults (Mean age = 76.06, sex = 12 males) participated in this repeated measures study. A final follow-up was then conducted post-lockdown to capture any factors that were viewed as helpful to well-being during lockdown. From pre- to during lockdown, perceived stress, well-being, depressive symptoms, mood disturbance and memory were all significantly worsened. There were significant improvements in self-reported physical health symptoms, social interaction, time spent engaging in physical activity and certain aspects of relationship quality. Follow-up showed that well-being, depression and mood were still negatively affected post-lockdown. Given the sample were all ‘healthy’ at baseline in comparison to established norms, there may be greater impairment in more vulnerable populations. Support for older populations is needed to mitigate the negative effects shown, particularly in light of the endurance of some of these effects post-lockdown.

An individual differences investigation of the relations among life event stress, working memory capacity, and mind wandering: A preregistered replication-extension study

Klein and Boals (2001a, Applied Cognitive Psychology, 15[5], 565-579, Experiments 1 and 2) found that working memory capacity correlated negatively with perceived negative life event stress and speculated the relation may be driven by thoughts produced from these experiences. Here, we sought to replicate the association between working memory capacity and perceived negative life experience and to assess potential mediators of this association such as mind wandering propensity, rumination propensity, and the sum of negatively valenced mind wandering reports. In this preregistered replication and extension study, with data collected from 356 subjects (ns differ among analyses), we found no evidence suggesting that perceived negative life stress is associated with working memory capacity. Additionally, we found evidence consistent with the claim that negatively valenced mind wandering is uniquely detrimental to cognitive task performance, but we highlight a potential confound that may account for this association that should be addressed in future work.

Examining the effect of stress induction on auditory working memory performance for emotional and non-emotional stimuli in female students

Background

Theoretical frameworks have shown that stress might influence working memory in different ways. Previous research has investigated the effect of stress on female's working memory but there is lack of evidence regarding the impact of emotional aspects.

Objectives

This study examined the effect of stress induction on auditory working memory (AWM) performance among university students for emotional (positive and negative) and non-emotional (neutral) stimuli.

Methods

A sample of 102 female students at the Universities of Isfahan, Iran was selected using convenience sampling in 2018. Participants completed the demographic information sheets, then, they were randomly assigned into the experimental and control groups. The stress was induced by the Socially Evaluated Cold Pressor Test (SECPT). An n-back task was presented pre and post of stress induction, to evaluate the AWM performance (accuracy and reaction time). The research data were analyzed using mixed-model ANOVA.

Results

Both accuracy and reaction time (RT) scores were found to be enhanced for positive words in the experimental condition. However, accuracy and RT indices were found to be worsening for negative words in the experimental condition.

Conclusions

This study supports the idea that stress influences AWM performance depend on emotionally-valenced stimuli, which may help us to better understand the underlying mechanisms of memory processing.

Associations between lifetime stress exposure, race, and first-birth intendedness in the United States

This study examined how lifetime stress exposure and race are associated with first-birth intendedness, and whether these associations differ based on stress exposure timing. Greater lifetime stress exposure was related to increased first-birth intendedness for black women but was unrelated or even associated with decreased first-birth intendedness for white women, depending on stress exposure timing. These effects were robust while controlling for age, partner status, household income, and education, and they differed based on the timing of participants' stress exposure. These data thus provide evidence that first-birth intendedness is influenced by both lifetime stress exposure and race in the United States.

Short sleep duration and high exposure to quick returns are associated with impaired everyday memory in shift workers

PURPOSE

To investigate the relationship between self-reported everyday memory problems the last month, and: (a) shift work schedule, (b) night shifts and quick returns worked the last year, and (c) sleep duration the last month.

METHODS

In all, 1,275 nurses completed the Everyday Memory Questionnaire - revised, and answered questions about shift work exposure and sleep duration. We performed multiple linear regression analyses with memory score as dependent variable, and the shift work exposure variables as well as sleep duration as predictors, while adjusting for potential confounders.

FINDINGS

High exposure to quick returns (β = .10, p < .05) and short sleep duration (β = .10, p < .05) were both positively associated with memory problems, whereas shift work schedule, long sleep duration, night shift exposure, and low and moderate exposure to quick returns were not.

DISCUSSION

Frequent insufficient time for rest between shifts as well as short sleep was associated with poorer everyday memory.

Life Stress and Suicide in Adolescents

Stress exposure is central to theories of suicide. To advance understanding of the relation between stress and suicide, we examined whether specific, theoretically-pertinent life stressors were differentially related to suicidal thinking versus suicidal behaviors among hospitalized adolescents. Participants were 197 (144 female) adolescents aged 13 to 19 years old (M = 15.61, SD = 1.48) recruited from an acute residential psychiatric treatment program. Participants were categorized into mutually exclusive groups: psychiatric controls (n = 38) with no lifetime history of suicide ideation or suicide attempts, suicide ideators (n = 99) with current ideation and no lifetime attempts, and suicide attempters (n = 60) with a lifetime history of suicide ideation and at least one attempt in the past month. Adolescents completed the Stress and Adversity Inventory for Adolescents (Adolescent STRAIN), which assessed life events and chronic difficulties occurring in five social-psychological categories: Interpersonal Loss, Physical Danger, Humiliation, Entrapment, and Role Change/Disruption. Additionally, they completed a structured interview and symptom questionnaires to capture concurrent psychopathology. Controlling for demographic and clinical covariates, only Interpersonal Loss events distinguished attempters from psychiatric controls (OR = 2.27) and ideators (OR = 1.49); no events or difficulties differentiated ideators from controls. These effects persisted when analyses were restricted to single attempters and when events following the most recent attempt were excluded. The findings elucidate potential social-environmental triggers of suicide. Ultimately, this may improve the identification of ideators most likely to make an attempt, enabling the deployment of targeted early interventions.

Effects of Embryonic Inflammation and Adolescent Psychosocial Environment on Cognition and Hippocampal Staufen in Middle-Aged Mice

Accumulating evidence has indicated that embryonic inflammation could accelerate age-associated cognitive impairment, which can be attributed to dysregulation of synaptic plasticity-associated proteins, such as RNA-binding proteins (RBPs). Staufen is a double-stranded RBP that plays a critical role in the modulation of synaptic plasticity and memory. However, relatively few studies have investigated how embryonic inflammation affects cognition and neurobiology during aging, or how the adolescent psychosocial environment affects inflammation-induced remote cognitive impairment. Consequently, the aim of this study was to investigate whether these adverse factors can induce changes in Staufen expression, and whether these changes are correlated with cognitive impairment. In our study, CD-1 mice were administered lipopolysaccharides (LPS, 50 μg/kg) or an equal amount of saline (control) intraperitoneally during days 15–17 of gestation. At 2 months of age, male offspring were randomly exposed to stress (S), an enriched environment (E), or not treated (CON) and then assigned to five groups: LPS, LPS+S, LPS+E, CON, and CON+S. Mice were evaluated at 3-month-old (young) and 15-month-old (middle-aged). Cognitive function was assessed using the Morris water maze test, while Staufen expression was examined at both the protein and mRNA level using immunohistochemistry/western blotting and RNAscope technology, respectively. The results showed that the middle-aged mice had worse cognitive performance and higher Staufen expression than young mice. Embryonic inflammation induced cognitive impairment and increased Staufen expression in the middle-aged mice, whereas adolescent stress/an enriched environment would accelerated/mitigated these effects. Meanwhile, Staufen expression was closely correlated with cognitive performance. Our findings suggested embryonic inflammation can accelerate age-associated learning and memory impairments, and these effects may be related to the Staufen expression.

Differential impact of stress and environmental enrichment on corticolimbic circuits

Stress exposure can produce profound changes in physiology and behavior that can impair health and well-being. Of note, stress exposure is linked to anxiety disorders and depression in humans. The widespread impact of these disorders warrants investigation into treatments to mitigate the harmful effects of stress. Pharmacological treatments fail to help many with these disorders, so recent work has focused on non-pharmacological alternatives. One of the most promising of these alternatives is environmental enrichment (EE). In rodents, EE includes social, physical, and cognitive stimulation for the animal, in the form of larger cages, running wheels, and toys. EE successfully reduces the maladaptive effects of various stressors, both as treatment and prophylaxis. While we know that EE can have beneficial effects under stress conditions, the morphological and molecular mechanisms underlying these behavioral effects are still not well understood. EE is known to alter neurogenesis, dendrite development, and expression of neurotrophic growth factors, effects that vary by type of enrichment, age, and sex. To add to this complexity, EE has differential effects in different brain regions. Understanding how EE exerts its protective effects on morphological and molecular levels could hold the key to developing more targeted pharmacological treatments. In this review, we summarize the literature on the morphological and molecular consequences of EE and stress in key emotional regulatory pathways in the brain, the hippocampus, prefrontal cortex, and amygdala. The similarities and differences among these regions provide some insight into stress-EE interaction that may be exploited in future efforts toward prevention of, and intervention in, stress-related diseases.

Stress & executive functioning: A review considering moderating factors

A multitude of studies investigating the effects of stress on cognition has produced an inconsistent picture on whether - and under which conditions - stress has advantageous or disadvantageous effects on executive functions (EF). This review provides a short introduction to the concept of stress and its neurobiology, before discussing the need to consider moderating factors in the association between stress and EF. Three core domains are described and discussed in relation to the interplay between stress and cognition: the influence of different paradigms on physiological stress reactivity, individual differences in demographic and biological factors, and task-related features of cognitive tasks. Although some moderating variables such as the endocrine stress response have frequently been considered in single studies, no attempt of a holistic overview has been made so far. Therefore, we propose a more nuanced and systematic framework to study the effects of stress on executive functioning, comprising a holistic overview from the induction of stress, via biological mechanisms and interactions with individual differences, to the influence of stress on cognitive performance.

Perceived control moderates the impact of academic stress on the attention process of working memory in male college students

Academic stress is a common long-term stress among the student population and is known to impact working memory within the frontoparietal attention network. Perceived control is an individual variation that may play a buffering role between stress and overall adjustment. In this study, we addressed the moderating effects of perceived control between academic stress and working memory. Fifty-nine male college students participated in the study. Academic stress and perceived control were assessed before participants completed a working memory (n-back) task. Event-related potentials (ERPs) including P2 and P3 were analyzed to examine the attention and maintenance processes of working memory. A moderating effect of perceived control on the relationship between academic stress and working memory was found. For students with low levels of perceived control, academic stress was negatively associated with P2 amplitudes at the high workload (3-back) task, suggesting a negative impact on attention process of working memory. In contrast, academic stress did not affect students with high and moderate levels of perceived control. The results indicate that perceived control may serve as a buffer to protect the cognitive function from the disruption of academic stress.

A Combined Treatment Approach to Support Everyday Function and Promote Brain Health in Older Adults: A Pilot Study

Objective: Subtle changes in functional abilities are an early indicator of cognitive impairment. Early intervention may be key to prolonging independence. This study describes the development and program evaluation of an intervention designed to (1) bolster the use of compensation strategies that support everyday executive and memory functioning and (2) utilize these strategies to promote engagement in brain health activities.Method: Older adults (n = 35) with subjective cognitive complaints completed an eight-week group program targeting compensation strategies (e.g., calendars) and brain health activities (e.g., physical exercise). Participants completed outcome measures at first, last, and 3 month follow-up sessions.Results: Compensation strategy use can be successfully taught to and implemented by older adults, and increasing engagement in brain health behaviors is possible, although particular lifestyle changes are challenging to implement.Conclusion: Findings support the use of interventions aimed at increased engagement in compensation strategies to aid everyday memory and executive functioning.Clinical Implications: Early intervention may help to promote prolonged functional independence.

Poor inhibition of personally-relevant facial expressions of sadness and anger predicts an elevated cortisol response following awakening six months later

Failure to inhibit interference from distracting emotional stimuli may obstruct an individual's ability to regulate their behavioural and emotional responses to environmental stressors. Few studies have examined the longitudinal association between cognitive inhibition and regulation of the hypothalamic-pituitary-adrenal axis (HPA) in the natural environment. Seventy-nine healthy adults underwent two assessments 6 months apart. Participants' ability to suppress interference from distracting emotional stimuli was assessed using a negative affective priming task that included both generic and personally-relevant (i.e., participants' intimate partners) facial expressions of emotion. Poorer inhibition of personally-relevant sad and angry faces, but not generic stimuli, significantly predicted an increased cortisol awakening response (CAR) six months later. Moreover, poor inhibition of personally-relevant sad faces mediated the relation between chronic stress and an elevated CAR. Difficulties inhibiting personally-relevant emotional information may represent a key mechanism in understanding how environmental stress influences HPA functioning.

The Stress and Adversity Inventory for Adults (Adult STRAIN) in Brazilian Portuguese: Initial Validation and Links With Executive Function, Sleep, and Mental and Physical Health

It has been widely hypothesized that stressors occurring over the lifespan exert a cumulative impact on health, but little work has directly tested these theories given the difficulty associated with measuring cumulative stress exposure over the lifespan. We addressed this issue in Brazil by translating the Stress and Adversity Inventory for Adults (Adult STRAIN) into Brazilian Portuguese. We then examined the instrument's usability and acceptability; concurrent, discriminant, predictive, and incremental validity; and test-retest reliability. Participants were 330 Brazilian adults (238 women; M age = 32.16; range: 18-76 years old) who completed the Adult STRAIN in Brazilian Portuguese, Childhood Trauma Questionnaire-Short Form (CTQ-SF), and Perceived Stress Scale (PSS). They also completed measures of socioeconomic status, personality, social desirability, negative affect, physical and mental health complaints, sleep quality, executive function, and doctor-diagnosed general health problems and autoimmune disorders. The STRAIN exhibited excellent usability and acceptability and was completed in 16 min and 27 s, on average. It showed good concurrent validity relative to the CTQ-SF and PSS (rs ≥ 0.377) and good discriminant validity, both with and without adjusting for covariates. In addition, the STRAIN significantly predicted all of the health outcomes assessed except for executive function and explained substantial variance in these outcomes over and above the CTQ-SF, PSS, and covariates assessed. Finally, the test-retest reliability indices for total lifetime stressor count and severity were outstanding (r icc = 0.936 and 0.953, respectively, over M = 34.86 days). The Adult STRAIN in Brazilian Portuguese thus exhibits excellent usability and acceptability, good concurrent and discriminant validity, strong predictive and incremental validity across a variety of health outcomes, and outstanding test-retest reliability. We therefore conclude that the STRAIN is a practical, valid, and reliable instrument for researchers and clinicians looking to efficiently assess cumulative lifetime stress exposure in Brazilian Portuguese.

The Stress and Adversity Inventory for Adolescents (Adolescent STRAIN): associations with mental and physical health, risky behaviors, and psychiatric diagnoses in youth seeking treatment

BACKGROUND

Numerous theories have posited that stressors occurring over the lifespan may exert a cumulative effect on psychological and biological processes that increase individuals' risk for a variety of mental and physical health problems. Given the difficulty associated with assessing lifetime stress exposure, however, few empirical studies have directly tested these cumulative risk models of psychopathology and human health.

METHOD

To address this issue, we examined the usability, acceptability, concurrent validity, and predictive validity of the recently developed Stress and Adversity Inventory for Adolescents (Adolescent STRAIN) in 338 youth (M_age  = 15.64; 229 females) seeking mental health treatment.

RESULTS

The Adolescent STRAIN achieved high acceptability and was completed in approximately 25 min (interquartile range: 20-32 min). Concurrent associations with other measures of early adversity (Childhood Trauma Questionnaire-Short Form) and interpersonal stress (Revised Peer Experiences Questionnaire) were very good (rs = .50-.59). In analyses that adjusted for participants' age, sex, and race, the STRAIN was significantly associated with depression, anxiety, and anhedonia severity; general mental and physical health complaints; risky behavior engagement; and number of interviewer-based psychiatric diagnoses (βs = .16-.52; risk ratios = 1.006-1.014). Contrary to classic theories of stress which assume that different stressors exert similar effects on health, substantial differences were observed across the two stressor types, twelve life domains, and five core social-psychological characteristics assessed by the Adolescent STRAIN.

CONCLUSIONS

These data confirm the relevance of lifetime stress exposure for multiple health outcomes in adolescence, which can in turn inform existing theories of lifespan health. Because stress is a common presenting problem in hospitals and clinics, these data also suggest the possibility of using the Adolescent STRAIN to generate stress exposure profiles for case conceptualization and treatment planning purposes.

Stress and the medial temporal lobe at rest: Functional connectivity is associated with both memory and cortisol

When acute stress is experienced immediately after memory encoding (i.e., post-encoding stress) it can significantly impact subsequent memory for that event. For example, recent work has suggested that post-encoding stress occurring in a different context from encoding impairs memory. However, the neural processes underlying these effects are poorly understood. We aimed to expand this understanding by conducting an analysis of resting functional connectivity in the period following post-encoding stress that occurred in a different context than encoding, using seed regions in the medial temporal lobes known for their roles in memory. In the current study of 44 males randomized to stress (n = 23) or control (n = 21) groups, we found that stress increased cortisol, impaired recollection of neutral materials, and altered functional connectivity with medial temporal lobe regions. Although stress did not significantly alter hippocampus-amygdala functional connectivity, relative to participants in the control group, participants in the post-encoding stress group showed lower functional connectivity between the hippocampus and a region with a peak in the superior temporal gyrus. Across participants in both groups, functional connectivity between these regions was related to greater increases in cortisol, and it was also inversely related to recollection of neutral materials. In contrast, the stress group showed greater parahippocampal cortex functional connectivity with a region in the left middle temporal gyrus than the control group. Moreover, greater functional connectivity between the parahippocampal cortex and the observed cluster in the middle temporal gyrus was associated with greater cortisol changes from pre- to post-manipulation, but was not related to differences in memory. The results show that post-encoding stress can alter the resting-state functional connectivity between the medial temporal lobe and neocortex, which may help explain how stress impacts memory.

Handling stress impairs learning through a mechanism involving caspase-1 activation and adenosine signaling

Acute stressors can induce fear and physiologic responses that prepare the body to protect from danger. A key component of this response is immune system readiness. In particular, inflammasome activation appears critical to linking stress to the immune system. Here, we show that a novel combination of handling procedures used regularly in mouse research impairs novel object recognition (NOR) and activates caspase-1 in the amygdala. In male mice, this handling-stress paradigm combined weighing, scruffing and sham abdominal injection once per hr. While one round of weigh/scruff/needle-stick had no impact on NOR, two rounds compromised NOR without impacting location memory or anxiety-like behaviors. Caspase-1 knockout (KO), IL-1 receptor 1 (IL-1R1) KO and IL-1 receptor antagonist (IL-RA)-administered mice were resistant to handling stress-induced loss of NOR. In addition, examination of the brain showed that handling stress increased caspase-1 activity 85% in the amygdala without impacting hippocampal caspase-1 activity. To delineate danger signals relevant to handling stress, caffeine-administered and adenosine 2A receptor (A2AR) KO mice were tested and found resistant to impaired learning and caspase-1 activation. Finally, mice treated with the β-adrenergic receptor antagonist, propranolol, were resistant to handling stress-induced loss of NOR and caspase-1 activation. Taken together, these results indicate that handling stress-induced impairment of object learning is reliant on a pathway requiring A2AR-dependent activation of caspase-1 in the amygdala that appears contingent on β-adrenergic receptor functionality.

The cerebellum under stress

Stress-related psychiatric conditions are one of the main causes of disability in developed countries. They account for a large portion of resource investment in stress-related disorders, become chronic, and remain difficult to treat. Research on the neurobehavioral effects of stress reveals how changes in certain brain areas, mediated by a number of neurochemical messengers, markedly alter behavior. The cerebellum is connected with stress-related brain areas and expresses the machinery required to process stress-related neurochemical mediators. Surprisingly, it is not regarded as a substrate of stress-related behavioral alterations, despite numerous studies that show cerebellar responsivity to stress. Therefore, this review compiles those studies and proposes a hypothesis for cerebellar function in stressful conditions, relating it to stress-induced psychopathologies. It aims to provide a clearer picture of stress-related neural circuitry and stimulate cerebellum-stress research. Consequently, it might contribute to the development of improved treatment strategies for stress-related disorders.

The Stress and Adversity Inventory for Adults (Adult STRAIN) in German: An overview and initial validation

Life stress is a key determinant of poor mental and physical health, but until recently no instrument existed for efficiently assessing cumulative stress exposure and severity across the entire lifespan. The Stress and Adversity Inventory (STRAIN) is an online, interview-based stress assessment system that was developed to address this need. We examined the concurrent, predictive, and discriminant validity of a German translation of the STRAIN by administering the instrument, along with several other measures of stress and health, to 298 adults (81 men, 217 women, M_age = 30.3 years). The German STRAIN demonstrated excellent concurrent validity, as evidenced by associations with other instruments assessing early adversity (|rs|≥.62, ps≤.001). It also correlated with instruments assessing recent life event exposure in adulthood (|rs|≥.48, ps≤.001), as well as recent perceived stress (|rs|≥ .25, ps≤.001) and recent chronic stress levels (|rs|≥ .19, ps≤.001). Additionally, the German STRAIN showed strong predictive validity in relation to anxiety symptoms (|rs|≥ .22, ps≤.001) and depressive symptoms (|rs|≥ .33, ps≤.001). Finally, the German STRAIN showed good discriminant validity, with lifetime stressor count being unrelated to personality features like neuroticism. These results demonstrate that the German version of the STRAIN is a valid tool for assessing lifetime stress exposure and severity. Additional research is needed to examine how the German STRAIN predicts psychological and biological stress reactivity and physical health outcomes.

Determining the mechanisms through which recent life stress predicts working memory impairments: precision or capacity?

Prior research has found that recent life stress exposure is related to poorer working memory performance, but it remains unclear which aspects of working memory are related to stress. To address this important issue, we examined the extent to which recent life stress exposure was associated with working memory capacity (i.e., the number of items that can be held in working memory) and working memory precision (i.e., the quality of representations of items held within working memory) in a sample of 260 healthy young adults (M_age= 19.95 years old; range = 18-33). Recent life stress exposure and working memory were assessed with the Stress and Adversity Inventory for Daily Stress (Daily STRAIN) and color wheel task, respectively. We found that recent life stress was selectively associated with lower working memory capacity; moreover, the association of recent life stress with capacity was significantly stronger in magnitude than the non-significant association of recent life stress with precision. These associations were robust while controlling for potential confounds, including demographic factors, negative affect, and cumulative lifetime stress exposure. These results thus suggest that stress-related degradations in working memory capacity may help explain how recent life stress exposure affects working memory performance.

Chronic stress: a critical risk factor for atherosclerosis

Chronic stress refers to the non-specific systemic reaction that occurs when the body is stimulated by various internal and external negative factors over a long time. The physiological response to chronic stress exposure has long been recognized as a potent modulator in the occurrence of atherosclerosis. Furthermore, research has confirmed the correlation between atherosclerosis and cardiovascular events. Chronic stress is pervasive during negative life events and may lead to the formation of plaque. Several epidemiological studies have shown that chronic stress is an independent risk factor for the development of vascular disease and for increased morbidity and mortality in patients with pre-existing coronary artery disease. One possible mechanism for this process is that chronic stress causes endothelial injury, directly activating macrophages, promoting foam cell formation and generating the formation of atherosclerotic plaque. This mechanism involves numerous variables, including inflammation, signal pathways, lipid metabolism and endothelial function. The mechanism of chronic stress in atherosclerosis should be further investigated to provide a theoretical basis for efforts to eliminate the effect of chronic stress on the cardiocerebral vascular system.

Subjective and physiological stress measurement in a multiple sclerosis sample and the relation with executive functions performance

In multiple sclerosis (MS), hypothalamic-pituitary-adrenal (HPA) axis functioning may be dysregulated due to the high cortisol levels involved in the disease activity. HPA axis dysregulation can affect cognitive performance, including executive functions. This study aimed to evaluate hair cortisol concentration and perceived stress as well as verify the association with the performance of executive function in both individuals diagnosed with MS and control individuals. Hair cortisol concentration and perceived stress were evaluated and their association with the performance of healthy individuals (n = 33) and those with MS (n = 64), most of them with remitting-relapsing multiple sclerosis (RRMS) assessed using the Expanded Disability Status Scale (EDSS). Instruments that were employed to measure perceived stress and health aspects included the Behavioral Assessment Dysexecutive Syndrome, Wisconsin Card Sorting Test, Stroop Test, and Perceived Stress Scale. No significant statistical difference was found in the comparison of means among the groups; however, an association was found when using statistical correlation tests between cortisol and cognitive performance in the clinical group (r = 0.31, p = 0.10). Further, an absence of correlations with perceived stress measure was noted. It was possible to observe interaction between group factors and low level of cortisol and problem-solving/cognitive flexibility in the MS group. The results indicated that stress measures used in the present study seem to influence the performance of inhibitory control and problem-solving/cognitive flexibility, the latter with low levels of cortisol in individuals with MS. We suggest studies that examine different measures of physiological stress and characteristics of the disease such as more time of stress.

Greater Lifetime Stress Exposure Predicts Blunted Cortisol but Heightened DHEA Responses to Acute Stress

Although prior research has examined how early adversity and chronic stress exposure relate to hypothalamic-pituitary-adrenal (HPA) axis responses to acute stress, to date, no studies have examined how stressors occurring over the entire lifespan predict such responses. To address this issue, we recruited 61 healthy young adults and measured their exposure to 55 different types of acute life events and chronic difficulties occurring over the lifespan. In addition, we characterized differences in participants' HPA axis responses to acute stress by measuring their salivary cortisol and DHEA responses to the Trier Social Stress Test for Groups. Greater cumulative stress exposure was associated with a blunted cortisol response, but a heightened DHEA response, to the acute stressor. Moreover, it was participants' exposure to these stressors (i.e., lifetime count), not their perceived severity, which predicted their cortisol and DHEA responses to acute stress. Furthermore, differential effects were observed by stress exposure domain. Notably, only adulthood and marital/partner stressors significantly predicted cortisol responses to acute stress, whereas stress was more uniformly associated with DHEA responses to the acute stressor. These results thus reveal how cumulative stress exposure is associated with HPA axis responsivity to acute stress, while highlighting the fact that different stressors may have substantially different associations with these biological outcomes.

Millennials and contraception: why do they forget? An international survey exploring the impact of lifestyles and stress levels on adherence to a daily contraceptive regimen

BACKGROUND

Rates of unintended pregnancies are particularly high in young women, a finding that may be associated with their tendency not to use contraceptives correctly and/or consistently. For millennial women, busy lifestyles and associated stress may impact on daily activities including taking an oral contraceptive pill.

METHODS

Contraceptive pill users aged 21-29 years ('millennial' women; N = 4500) from nine countries in Europe and North and South America completed an online questionnaire on their daily habits and activities, disruptions to their routine and associated stress levels.

RESULTS

Thirty-nine percent of surveyed participants had forgotten to take their contraceptive pill at least once in the past month; 39% also admitted not taking it at the same time each day. On average, participants had experienced two major disruptions to their daily lives in the past year, with three quarters (74%) believing these disruptions increased their stress levels. Of those who had missed at least one pill in the past year, 40% attributed it to a busy schedule and 21% to stress, among other reasons. Over half of respondents (55%) reported they were more likely to forget their pill when preoccupied.

CONCLUSIONS

Times of stress may make it more likely for millennial women to forget to take their pill. Health care providers should be aware of typical contraceptive adherence rates among young women and ensure that contraceptive counselling sessions include discussion of lifestyle issues and potential barriers to adherence. Every woman should be counselled on all available methods, so that she can make an informed choice on what best suits her.

High Exploratory Phenotype Rats Exposed to Environmental Stressors Present Memory Deficits Accompanied by Immune-Inflammatory/Oxidative Alterations: Relevance to the Relationship Between Temperament and Mood Disorders

Low-exploratory (LE) and high-exploratory (HE) rodents mimic human depressive and hyperthymic temperaments, respectively. Mood disorders (MD) may be developed by the exposure of these temperaments to environmental stress (ES). Psychiatric symptoms severity in MD patients is related to the magnitude of memory impairment. Thus, we aimed at studying the consequences of the exposure of LE and HE male Wistar rats, during periadolescence, to a combination of ES, namely, paradoxical sleep deprivation (PSD) and unpredictable stress (US), on anxiety-related behavior in the plus maze test, working (WM) and declarative memory (DM) performance. We also evaluated hippocampal immune-inflammatory/oxidative, as consequences of ES, and prevention of ES-induced alterations by the mood-stabilizing drugs, lithium and valproate. Medium exploratory (ME) control rats were used for comparisons with HE- and LE-control rats. We observed that HE-controls presented increased anxiolytic behavior that was significantly increased by ES exposure, whereas LE-controls presented increased anxiety-like behavior relative to ME-controls. Lithium and valproate prevented anxiolytic alterations in HE+ES rats. HE+ES- and LE+ES-rats presented WM and DM deficits. Valproate and lithium prevented WM deficits in LE-PSD+US rats. Lithium prevented DM impairment in HE+ES-rats. Hippocampal levels of reduced glutathione (GSH) increased four-fold in HE+ES-rats, being prevented by valproate and lithium. All groups of LE+ES-rats presented increased levels of GSH in relation to controls. Increments in lipid peroxidation in LE+ES- and HE+ES-rats were prevented by valproate in HE+ES-rats and by both drugs in LE+ES-rats. Nitrite levels were increased in HE+ES- and LE+ES-rats (five-fold increase), which was prevented by both drugs in LE+ES-rats. HE+ES-rats presented a two-fold increase in the inducible nitric oxide synthase (iNOS) expression that was prevented by lithium. HE+ES-rats showed increased hippocampal and plasma levels of interleukin (IL)-1β and IL-4. Indoleamine 2, 3-dioxygenase 1 (IDO1) was increased in HE+ES- and LE+ES-rats, while tryptophan 2,3-dioxygenase (TDO2) was increased only in HE+ES-rats. Altogether, our results showed that LE- and HE-rats exposed to ES present distinct anxiety-related behavior and similar memory deficits. Furthermore, HE+ES-rats presented more brain and plasma inflammatory alterations that were partially prevented by the mood-stabilizing drugs. These alterations in HE+ES-rats may possibly be related to the development of mood symptoms.

Acute and past subjective stress influence working memory and related neural substrates

Stress has been proposed to affect cognitive control capacities, including working memory (WM) maintenance. This effect may depend on variability in stress reactivity and past subjective stress. However, as most studies employed between-subjects designs, evidence for within-subject stress effects remains scarce. To understand the role of intra-individual stress effects on WM, we adopted a within-subject design to study how acute stress, variability in stress reactivity, and past subjective stress influence behavioral and neural WM mechanisms. Thirty-four healthy males performed a WM task during functional magnetic resonance imaging (fMRI) in a control versus acute stress condition following the Trier Social Stress Test, a validated psychosocial stressor method. We tested for stress effects on WM performance and related neural activation by associating them with individual acute stress responsivity and past subjective stress experience using retrospective self-report questionnaires. We found no evidence of an effect of acute stress or related stress-reactivity on intra-individual WM performance. However, past subjective stress negatively influenced acute stress-induced changes to WM. On the neural level, acute stress reduced WM-related activation in the dorsolateral prefrontal cortex (dlPFC). The observed negative influence of inter-individual variability in past subjective stress experience on changes in WM performance, suggests that past subjective stress might induce vulnerability for impairing effects of acute stress on cognitive functioning. Because acute stress reduced WM-related dlPFC activation while WM performance remained unaffected, acute stress might boost neural processing efficiency in this group of high performing healthy individuals. Our study suggests that measures of past subjective stress should be considered when studying and interpreting the effects of acute stress on cognition.

More than a feeling: A unified view of stress measurement for population science

Stress can influence health throughout the lifespan, yet there is little agreement about what types and aspects of stress matter most for human health and disease. This is in part because "stress" is not a monolithic concept but rather, an emergent process that involves interactions between individual and environmental factors, historical and current events, allostatic states, and psychological and physiological reactivity. Many of these processes alone have been labeled as "stress." Stress science would be further advanced if researchers adopted a common conceptual model that incorporates epidemiological, affective, and psychophysiological perspectives, with more precise language for describing stress measures. We articulate an integrative working model, highlighting how stressor exposures across the life course influence habitual responding and stress reactivity, and how health behaviors interact with stress. We offer a Stress Typology articulating timescales for stress measurement - acute, event-based, daily, and chronic - and more precise language for dimensions of stress measurement.