Low lifetime stress exposure is associated with reduced stimulus-response memory

Acute Stress Effects on Statistical Learning and Episodic Memory

Stress is widely considered to negatively impact hippocampal function, thus impairing episodic memory. However, the hippocampus is not merely the seat of episodic memory. Rather, it also (via distinct circuitry) supports statistical learning. On the basis of rodent work suggesting that stress may impair the hippocampal pathway involved in episodic memory while sparing or enhancing the pathway involved in statistical learning, we developed a behavioral experiment to investigate the effects of acute stress on both episodic memory and statistical learning in humans. Participants were randomly assigned to one of three conditions: stress (socially evaluated cold pressor) immediately before learning, stress ∼15 min before learning, or no stress. In the learning task, participants viewed a series of trial-unique scenes (allowing for episodic encoding of each image) in which certain scene categories reliably followed one another (allowing for statistical learning of associations between paired categories). Memory was assessed 24 hr later to isolate stress effects on encoding/learning rather than retrieval. We found modest support for our hypothesis that acute stress can amplify statistical learning: Only participants stressed ∼15 min in advance exhibited reliable evidence of learning across multiple measures. Furthermore, stress-induced cortisol levels predicted statistical learning retention 24 hr later. In contrast, episodic memory did not differ by stress condition, although we did find preliminary evidence that acute stress promoted memory for statistically predictable information and attenuated competition between statistical and episodic encoding. Together, these findings provide initial insights into how stress may differentially modulate learning processes within the hippocampus.

Impact of lifetime stressor exposure on neuroenergetics in schizophrenia spectrum disorders

N-acetylasparate and lactate are two prominent brain metabolites closely related to mitochondrial functioning. Prior research revealing lower levels of NAA and higher levels of lactate in the cerebral cortex of patients with schizophrenia suggest possible abnormalities in the energy supply pathway necessary for brain function. Given that stress and adversity are a strong risk factor for a variety of mental health problems, including psychotic disorders, we investigated the hypothesis that stress contributes to abnormal neuroenergetics in patients with schizophrenia. To test this hypothesis, we used the Stress and Adversity Inventory (STRAIN) to comprehensively assess the lifetime stressor exposure profiles of 35 patients with schizophrenia spectrum disorders and 33 healthy controls who were also assessed with proton magnetic resonance spectroscopy at the anterior cingulate cortex using 3 Tesla scanner. Consistent with the hypothesis, greater lifetime stressor exposure was significantly associated with lower levels of N-acetylasparate (β = -0.36, p = .005) and higher levels of lactate (β = 0.43, p = .001). Moreover, these results were driven by patients, as these associations were significant for the patient but not control group. Though preliminary, these findings suggest a possible role for stress processes in the pathophysiology of abnormal neuroenergetics in schizophrenia.

Cumulative lifetime stressor exposure impairs stimulus-response but not contextual learning

Greater exposure to stressors over the life course is believed to promote striatum-dependent over hippocampus-dependent learning and memory processes under stressful conditions. However, little research in this context has actually assessed lifetime stressor exposure and, moreover, it remains unknown whether greater cumulative lifetime stressor exposure exerts comparable effects on striatum-dependent learning and hippocampus-dependent learning in non-stressful contexts. To investigate this issue, we used the Stress and Adversity Inventory for Adults (Adult STRAIN) and Multicued Search Task to investigate the relation between cumulative lifetime stressor exposure and striatum-dependent stimulus-response learning and hippocampus-dependent contextual learning under non-stressful conditions among healthcare professionals (N = 205; 157 females, 48 males; Age: M = 34.23, SD 9.3, range 20-59 years). Individuals with moderate, but not low, cumulative lifetime stressor exposure exhibited impaired learning for stimulus-response associations. In contrast, learning for context associations was unrelated to participants' lifetime stressor exposure profiles. These results thus provide first evidence that cumulative lifetime stressor exposure may have negative consequences on human striatum-dependent stimulus-response learning under non-stressful environmental conditions.

Lifecourse Traumatic Events and Cognitive Aging in the Health and Retirement Study

INTRODUCTION

Much of the heterogeneity in the rate of cognitive decline and the age of dementia onset remains unexplained, and there is compelling data supporting psychosocial stressors as important risk factors. However, the literature has yet to come to a consensus on whether there is a causal relationship and, if there is, its direction and strength. This study estimates the relationship between lifecourse traumatic events and cognitive trajectories and predicted dementia incidence.

METHODS

Using data on 7,785 participants aged ≥65 years from the Health and Retirement Study, this study estimated the association between lifecourse experience of 10 traumatic events (e.g., losing a child) and trajectories of Telephone Interview for Cognitive Status from 2006 to 2016 using linear mixed-effects models and predicted incident dementia from 2006 to 2014 using cumulative incidence functions (data analysis was in 2020-2022). Inverse probability weights accounted for loss to follow-up and confounding by sex, education, race/ethnicity, and age.

RESULTS

Experiencing 1 or more traumatic events over the lifecourse was associated with accelerated decline compared with experiencing no events (e.g., β= -0.05 [95% CI= -0.07, -0.02] Health and Retirement Study-Telephone Interview for Cognitive Status units/year; 1 vs 0 events). In contrast, experiencing traumatic events was associated with better cognitive function cross-sectionally. Furthermore, the impact of trauma on cognitive decline was of greater magnitude when it occurred after the age of 64 years. However, the magnitude and direction of association varied by the specific traumatic event. There were no associations with predicted incident dementia.

CONCLUSIONS

These results suggest that researchers and clinicians should not aggregate traumatic events for understanding the risk of accelerated cognitive decline.

Life course trajectories of chronic financial strain and acute stress reactivity: Steeling in response to recovery from strain

The steeling hypothesis suggests experiencing moderate strain may improve an individual's ability to cope with future strain, whereas crisis theory suggests that experiencing temporary strain will reduce the effect of future strain. The current study improves on past research by utilizing data from two independent prospective panel studies (one of 553 white rural Midwesterner women and 451 men and one of 624 African American women) spanning 26 and 22 years, respectively. We utilize growth mixture modeling to identify latent groups based on trajectories of financial strain and test interactions between class membership and later acute stressful events on chronic illness and physical health using three subscales from the RAND SF-12. We find being a group that experienced a period of temporary strain weakened the effect of later acute stressors on physical health for both samples and chronic illness for the African American sample. Results support crisis theory and highlight the importance of considering chronic strain as a life course process.

Cumulative lifetime stressor exposure assessed by the STRAIN predicts economic ambiguity aversion

Uncertainty is inherent in most decisions humans make. Economists distinguish between two types of decision-making under non-certain conditions: those involving risk (i.e., known outcome probabilities) and those that involve ambiguity (i.e., unknown outcome probabilities). Prior research has identified individual differences that explain risk preferences, but little is known about factors associated with ambiguity aversion. Here, we hypothesized that cumulative exposure to major psychosocial stressors over the lifespan might be one factor that predicts individuals’ ambiguity aversion. Across two studies (Study 1: n = 58, M_age = 25.7; Study 2: n = 188, M_age = 39.81), we used a comprehensive lifetime stressor exposure inventory (i.e., the Stress and Adversity Inventory for Adults, or STRAIN) and a standard economic approach to quantify risk and ambiguity preferences. Greater lifetime stressor exposure as measured by the STRAIN, particularly in early life, was associated with higher aversion to ambiguity but not risk preferences.

Uncertainty is a factor in most decisions. Here the authors quantify tolerance for two forms of economic uncertainty—risk and ambiguity—and show that greater lifetime stressor exposure (as assessed by a comprehensive lifetime stressor exposure inventory) was associated with higher aversion to decisions involving ambiguity, but not risk.

Determining the effects of training duration on the behavioral expression of habitual control in humans: a multilaboratory investigation

It has been suggested that there are two distinct and parallel mechanisms for controlling instrumental behavior in mammals: goal-directed actions and habits. To gain an understanding of how these two systems interact to control behavior, it is essential to characterize the mechanisms by which the balance between these systems is influenced by experience. Studies in rodents have shown that the amount of training governs the relative expression of these two systems: Behavior is goal-directed following moderate training, but the more extensively an instrumental action is trained, the more it becomes habitual. It is less clear whether humans exhibit similar training effects on the expression of goal-directed and habitual behavior, as human studies have reported contradictory findings. To tackle these contradictory findings, we formed a consortium, where four laboratories undertook a preregistered experimental induction of habits by manipulating the amount of training. There was no statistical evidence for a main effect of the amount of training on the formation and expression of habits. However, exploratory analyses suggest a moderating effect of the affective component of stress on the impact of training over habit expression. Participants who were lower in affective stress appeared to be initially goal-directed, but became habitual with increased training, whereas participants who were high in affective stress were already habitual even after moderate training, thereby manifesting insensitivity to overtraining effects. Our findings highlight the importance of the role of moderating variables such as individual differences in stress and anxiety when studying the experimental induction of habits in humans.

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.

Associations between lifetime stress exposure and prenatal health behaviors

Prenatal health behaviors can strongly influence risk of poor pregnancy birth outcomes. Although stress has been implicated in structuring the likelihood that individuals will engage in various prenatal health behavior patterns, no studies to date have examined life stress exposure occurring across the entire lifespan, and few have investigated how different types of stressors are comparatively associated with these outcomes. To address these issues, we interviewed 164 women at one of two large Midwestern, urban hospitals after delivering their first infant. We used the Stress and Adversity Inventory (STRAIN) to assess women's lifetime stress exposure severity and ordinary least squares regression models to examine associations between participants' life stress exposure and prenatal health behaviors. As hypothesized, greater lifetime stress exposure was associated with engaging in more negative prenatal health behaviors and fewer positive prenatal health behaviors while controlling for relevant sociodemographic factors and current perceived stress levels. These effects were stronger for negative versus positive health behaviors, and they differed substantially as a function of stressor type, exposure timing, and primary life domain. Stressors occurring over the life course thus have negative consequences for prenatal health behaviors, but these effects are not uniform across different types of life stress exposure.

Memory biases in alcohol use disorder: enhanced memory for contexts associated with alcohol prospectively predicts alcohol use outcomes

Memory for prior drinking experiences may powerfully drive later alcohol use in familiar drinking contexts, yet we know little about what patients with alcohol use disorder (AUD) remember of alcohol-related episodes. Although animal and theoretical models of addiction emphasize the importance of different memory systems for understanding maladaptive use, clinical research parsing what AUD patients remember from alcohol-related episodes is lacking. The current study applied a novel memory task in which moderate drinkers (N = 30) and treatment-seeking individuals with alcohol use disorder (AUD: N = 29) encoded associations between photographs of objects (alcoholic beverages and neutral items) and photographs of neutral scenes. At least 24 h later, two types of memory were assessed: item memory (object recognition) and associative memory (cued recognition of scenes associated with objects). To assess which memories predicted drinking, real-world behavior was assessed in patients with AUD at baseline and for 4 weeks following memory tests. Despite demographic differences, the results showed broadly impaired item memory in AUD compared with moderate drinkers (p < 0.001), but enhanced associative memory for scenes paired with alcohol (p = 0.015). These associative memory biases were especially pronounced for stimuli rated as more affectively salient. Furthermore, stronger but less detailed memory for alcohol-related associations (i.e., choosing the correct scene but the incorrect photograph) significantly predicted heavier baseline (p = 0.002) and higher subsequent (p = 0.01) drinking in patients with AUD. These findings reveal a novel alcohol-related memory bias in AUD, and uncover the importance of associative memory for understanding real-world heavy alcohol use.

Markers of a plant-based diet relate to memory and executive function in older adults

Background: Although it is known that plant-based foods are important for physical health, little is known about the relationship between plant-based foods and cognitive health. Emerging evidence suggests that some macronutrients may influence cognition, but it is unclear which domains of cognition are involved; more importantly, it is unknown how a plant-based diet relates to cognition.Objective: To examine associations between a plant-based dietary pattern and cognitive functioning.Methods: Participants were 3,039 older adults who participated in the 2011-2014 waves of the National Health and Nutrition Examination Survey (NHANES). The present cross-sectional study used data on macronutrient intake from 24-hour dietary interviews, as well as performance on tests of long-term memory and executive function (i.e., delayed word recall, digit symbol substitution test, and animal fluency). Principal component analysis was used to extract a dietary pattern consistent with a plant-based diet.Results: Greater adherence to a dietary pattern consistent with a plant-based diet was related to better performance on all cognitive tasks. Secondary analyses indicated that the associations between a plant-based dietary pattern and executive function accounted for the association between a plant-based dietary pattern and memory. Furthermore, this same plant-based dietary pattern was associated with reduced baseline inflammation in a separate dataset.Conclusions: Experimental manipulations are needed to determine the potential causal relations of these associations, but these results suggest that a plant-based diet relates to better cognition, especially through improved executive control. Future work should also attempt to extend these results by examining potential mechanisms underlying these associations, such as reduced inflammation.

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.

Threat-induced modulation of hippocampal and striatal memory systems during navigation of a virtual environment

The brain is composed of multiple memory systems that mediate distinct types of navigation. The hippocampus is important for encoding and retrieving allocentric spatial cognitive maps, while the dorsal striatum mediates procedural memories based on stimulus-response (S-R) associations. These memory systems are differentially affected by emotional arousal. In particular, rodent studies show that stress typically impairs hippocampal spatial memory while it spares or sometimes enhances striatal S-R memory. The influence of emotional arousal on these separate navigational memory systems has received less attention in human subjects. We investigated the effect of dynamic changes in anticipatory anxiety on hippocampal spatial and dorsal striatal S-R memory systems while participants attempted to solve a virtual eight-arm radial maze. In Experiment 1, participants completed a hippocampus-dependent spatial version of the eight-arm radial maze that required allocentric spatial memory to successfully navigate the environment. In Experiment 2, participants completed a dorsal striatal S-R version of the maze where no allocentric spatial cues were present, requiring the use of S-R navigation. Anticipatory anxiety was modulated via threat of receiving an unpleasant electrical shock to the wrist during memory retrieval. Results showed that threat of shock was associated with more errors and increased use of non-spatial navigational strategies in the hippocampal spatial task, but did not influence memory performance in the striatal S-R task. Findings indicate a dissociation regarding the influence of anticipatory anxiety on memory systems that has implications for understanding how fear and anxiety contribute to memory-related symptoms in human psychopathologies.

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.

Enhancing memory with stress: Progress, challenges, and opportunities

Stress can strongly influence what we learn and remember, including by making memories stronger. Experiments probing stress effects on hippocampus-dependent memory in rodents have revealed modulatory factors and physiological mechanisms by which acute stress can enhance long-term memory. However, extending these findings and mechanisms to understand when stress will enhance declarative memory in humans faces important challenges. This review synthesizes human and rodent studies of stress and memory, examining translational gaps related to measurements of declarative memory and stress responses in humans. Human studies diverge from rodent research by assessing declarative memories that may not depend on the hippocampus and by measuring peripheral rather than central stress responses. This highlights opportunities for future research across species, including assessing stress effects on hippocampal-dependent memory processes in humans and relating peripheral stress responses to stress effects on the function of memory-related brain regions in rodents. Together, these investigations will facilitate the translation of stress effects on memory function from rodents to humans and inform interventions that can harness the positive effects of stress on long-term memory.

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.

Learning strategies and the social brain: Missing elements in the link between developmental stress, song and cognition?

Bird songs may advertise aspects of cognition because song learning and learning speed in cognitive tasks are both affected by early-life environments. However, such relationships remain ambiguous in the literature. Here, I discuss 2 lines of research that may help to demystify links between song learning and cognition. First, learning strategies should be considered when assessing performance to ensure that individual differences in learning ability are not masked by individual differences in learning strategies. Second, song characteristics should be associated with social behavior because songs have a social purpose and, consequently, should be strongly related at functional and neural levels. Finally, if song learning and cognitive abilities are correlated because they develop concurrently and/or share or compete for the same resources, I discuss ways glucocorticoids may link early-life stress, song learning and cognitive ability, focusing particularly on oxidative stress as a potential mechanism.

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.

Assessing Lifetime Stress Exposure Using the Stress and Adversity Inventory for Adults (Adult STRAIN): An Overview and Initial Validation

OBJECTIVE

Numerous theories have proposed that acute and chronic stressors may exert a cumulative effect on life-span health by causing biological "wear and tear," or allostatic load, which in turn promotes disease. Very few studies have directly tested such models, though, partly because of the challenges associated with efficiently assessing stress exposure over the entire life course. To address this issue, we developed the first online system for systematically assessing lifetime stress exposure, called the Stress and Adversity Inventory (STRAIN), and describe its initial validation here.

METHODS

Adults recruited from the community (n = 205) were administered the STRAIN, Childhood Trauma Questionnaire-Short Form, and Perceived Stress Scale, as well as measures of socioeconomic status, personality, social desirability, negative affect, mental and physical health complaints, sleep quality, computer-assessed executive function, and doctor-diagnosed general health problems and autoimmune disorders.

RESULTS

The STRAIN achieved high acceptability and was completed relatively quickly (mean = 18 minutes 39 seconds; interquartile range = 12-23 minutes). The structure of the lifetime stress data best fit two latent classes overall and five distinct trajectories over time. Concurrent associations with the Childhood Trauma Questionnaire-Short Form and Perceived Stress Scale were good (r values = .147-.552). Moreover, the STRAIN was not significantly related to personality traits or social desirability characteristics and, in adjusted analyses, emerged as the measure most strongly associated with all six of the health and cognitive outcomes assessed except current mental health complaints (β values = .16-.41; risk ratios = 1.02-1.04). Finally, test-retest reliability for the main stress exposure indices over 2-4 weeks was excellent (r values = .904-.919).

CONCLUSIONS

The STRAIN demonstrated good usability and acceptability; very good concurrent, discriminant, and predictive validity; and excellent test-retest reliability.

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

Although substantial research has examined the effects of stress on cognition, much of this research has focused on acute stress (e.g. manipulated in the laboratory) or chronic stress (e.g. persistent interpersonal or financial difficulties). In contrast, the effects of recent life stress on cognition have been relatively understudied. To address this issue, we examined how recent life stress is associated with long-term, working memory, and self-reported memory in a sample of 142 healthy young adults who were assessed at two time points over a two-week period. Recent life stress was measured using the newly-developed Stress and Adversity Inventory for Daily Stress (Daily STRAIN), which assesses the frequency of relatively common stressful life events and difficulties over the preceding two weeks. To assess memory performance, participants completed both long-term and working memory tasks. Participants also provided self-reports of memory problems. As hypothesized, greater recent life stress exposure was associated with worse performance on measures of long-term and working memory, as well as more self-reported memory problems. These associations were largely robust while controlling for possible confounds, including participants' age, sex, and negative affect. The findings indicate that recent life stress exposure is broadly associated with worse memory. Future studies should thus consider assessing recent life stress as a potential predictor, moderator, or covariate of memory performance.

Lifetime Stress Exposure and Health: A Review of Contemporary Assessment Methods and Biological Mechanisms

Life stress is a central construct in health research because it is associated with increased risk for a variety of serious mental and physical health problems, including anxiety disorders, depression, cardiovascular disease, autoimmune disorders, Alzheimer's disease, certain cancers, and other diseases of aging. In this review, we examine how lifetime stress exposure contributes to elevated disease risk, and explore ongoing measurement and scientific issues related to this topic. To accomplish these goals, we first review existing instruments that have been developed for assessing perceived stress, self-reported life events, interviewer-assessed life stressors, and lifetime stress exposure. Next, we describe laboratory-based tasks that have been used for characterizing individual differences in psychological and biological stress reactivity. These methods have yielded an enormous amount of data showing how life stress influences the activity of the hypothalamic-pituitary-adrenal axis, hypothalamic-pituitary-gonadal axis, sympathetic-adrenal-medullary axis, and immune system, and how such processes can in turn cause allostatic load and biological embedding of the stress effect at the level of the human brain and genome. At the same time, many critical measurement and scientific issues remain unresolved, and we discuss these topics last while describing some pressing issues and opportunities for future research on stress and health.

Acute Stress Time-dependently Modulates Multiple Memory Systems

Acute stress has been shown to modulate the engagement of different memory systems, leading to preferential expression of stimulus-response (SR) rather than episodic context memory when both types of memory can be used. However, questions remain regarding the cognitive mechanism that underlies this bias in humans-specifically, how each form of memory is individually influenced by stress in order for SR memory to be dominant. Here we separately measured context and SR memory and investigated how each was influenced by acute stress after learning (Experiment 1) and before retrieval (Experiment 2). We found that postlearning stress, in tandem with increased adrenergic activity during learning, impaired consolidation of context memory and led to preferential expression of SR rather than context memory. Preretrieval stress also impaired context memory, albeit transiently. Neither postlearning nor preretrieval stress changed the expression of SR memory. However, individual differences in cortisol reactivity immediately after learning were associated with variability in initial SR learning. These results reveal novel cognitive mechanisms by which stress can modulate multiple memory systems.