Cortisol administration acutely reduces threat-selective spatial attention in healthy young men

The effects of yohimbine and hydrocortisone on selective attention to fearful faces: An fMRI study

INTRODUCTION

Selective attention to salient emotional information can enable an advantage in the face of danger. The present study aims to investigate the influence of the stress neuromodulators, norepinephrine and cortisol, on selective attention processes to fearful faces and its neuronal activation.

METHODS AND MATERIALS

We used a randomized, double-blind, placebo-controlled design. 167 healthy men between 18 and 35 years (mean [SD] age: 25.23 [4.24] years) participated in the study. Participants received either: (A) yohimbine (n= 41), (B) hydrocortisone (n = 41), (C) yohimbine and hydrocortisone (n = 42) or (D) placebo only (n= 43) and participated in a dot-probe task with fearful and neutral faces in an fMRI scanner.

RESULTS

We found an attentional bias toward fearful faces across all groups and related neuronal activation in the left cuneus. We did not find any differences between experimental treatment groups in selective attention and its neuronal activation.

DISCUSSION

Our results provide evidence that fearful faces lead to an attentional bias with related neuronal activation in the left cuneus. We did not replicate formerly reported activation in the amygdala, intraparietal sulcus, dorsal anterior cingulate cortex, and thalamus. Suitability of the dot-probe task for fMRI studies and insignificant treatment effects are discussed.

Acute stress reduces attentional blindness: Relations with resting respiratory sinus arrhythmia and cortisol

This study made the first attempt to combine resting respiratory sinus arrhythmia (RSA) and cortisol to provide an explanatory mechanism for the effect of acute stress on emotion-induced blindness (EIB) from the perspective of vagus nerve activity and stress hormone responses. For this purpose, resting electrocardiogram (ECG) signals were recorded first. Participants underwent both the socially evaluated cold-pressor test and control treatments 7 days apart and then completed the EIB task. Heart rate and saliva samples were collected over time. The results demonstrated that acute stress promoted the overall detection of targets. Resting RSA and cortisol levels predicted the stress-induced changes in EIB performance under the negative distractor condition at lag2 negatively and positively, respectively. These findings indicate that the effect of stress on EIB was partially contributed by cortisol, which is more relevant to negative distractor conditions. Resting RSA, as an indicator of inter-individual differences, further provided evidence from the perspective of the trait emotional regulation ability based on the vagus nerve control. In general, resting RSA and cortisol changes over time exhibit different patterns of influence on stress-induced changes in EIB performance. Thus, this study provides a more comprehensive understanding of the effect of acute stress on attentional blindness.

A Systematic Review of the Role of Oxytocin, Cortisol, and Testosterone in Facial Emotional Processing

A topic of interest is the way decoding and interpreting facial emotional expressions can lead to mutual understanding. Facial emotional expression is a basic source of information that guarantees the functioning of other higher cognitive processes (e.g., empathy, cooperativity, prosociality, or decision-making, among others). In this regard, hormones such as oxytocin, cortisol, and/or testosterone have been found to be important in modifying facial emotion processing. In fact, brain structures that participate in facial emotion processing have been shown to be rich in receptors for these hormones. Nonetheless, much of this research has been based on correlational designs. In recent years, a growing number of researchers have tried to carry out controlled laboratory manipulation of these hormones by administering synthetic forms of these hormones. The main objective of this study was to carry out a systematic review of studies that assess whether manipulation of these three hormones effectively promotes significant alterations in facial emotional processing. To carry out this review, PRISMA quality criteria for reviews were followed, using the following digital databases: PsycINFO, PubMed, Dialnet, Psicodoc, Web of Knowledge, and the Cochrane Library, and focusing on manuscripts with a robust research design (e.g., randomized, single- or double-blind, and/or placebo-controlled) to increase the value of this systematic review. An initial identification of 6340 abstracts and retrieval of 910 full texts led to the final inclusion of 101 papers that met all the inclusion criteria. Only about 18% of the manuscripts included reported a direct effect of hormone manipulation. In fact, emotional accuracy seemed to be enhanced after oxytocin increases, but it diminished when cortisol and/or testosterone increased. Nonetheless, when emotional valence and participants' gender were included, hormonal manipulation reached significance (in around 53% of the articles). In fact, these studies offered a heterogeneous pattern in the way these hormones altered speed processing, attention, and memory. This study reinforces the idea that these hormones are important, but not the main modulators of facial emotion processing. As our comprehension of hormonal effects on emotional processing improves, the potential to design good treatments to improve this ability will be greater.

Associations between Attention and Implicit Associative Learning in Healthy Adults: The Role of Cortisol and Salivary Alpha-Amylase Responses to an Acute Stressor

In this study, we investigated the associations between implicit associative learning with the cortisol and salivary alpha-amylase (sAA) stress response to an acute stressor as well as their associations with attention. Eighty one healthy adults (25 male) participated and either performed the socially evaluated cold-pressor test (SECPT) or a warm-water control task (WWT). Either prior to or immediately after the SECPT/WWT, participants implicitly learned digit-symbol pairs. A not-previously announced recall test was conducted about 20 min after the SECPT/WWT. Attention was assessed by means of a Stroop task at nine time points over the course of the experiment. Memory recall performance was not significantly associated with the acquisition time point (pre or post stressor) and did not significantly differ between the responder groups (i.e., non-responders, sAA-and-cortisol responders, only sAA responders, and only cortisol responders). Attentional performance increased throughout the experiment (i.e., reaction times in the Stroop task decreased). No differences in the attentional time course were found between the responder groups. However, some associations were found (p_uncorrected < 0.05) that did not pass the multiple comparison adjusted alpha level of α_adjusted = 0.002, indicating different associations between attention and implicit learning between the responder groups. We conclude that the associations of sAA and cortisol responses with implicit learning are complex and are related to each other. Further studies in which both (sAA and cortisol responses) are selectively (de-) activated are needed. Furthermore, different learning tasks and less—potentially stressful—attentional assessments should be used in future research. Moreover, field studies are needed in which the associations between acute stress and implicit associative learning are investigated in everyday life.

Prospective memory under acute stress: The role of (output) monitoring and ongoing-task demands

Prospective memory (PM) refers to the ability to postpone retrieval and execution of intended actions until the appropriate situation (PM cue) has come, while engaging in other ongoing activities or tasks. In everyday live we often perform PM tasks in stressful situations. While it has been shown that acute stress does not impair PM-cue identification and intention retrieval, little is known about acute stress effects on PM performance and memory for having performed an action (output monitoring) under varying ongoing-task demands. Here we investigated this in eighty healthy participants who performed event-based PM tasks during low- and high-demanding ongoing working memory tasks after having undergone either a standardized stress induction (Maastricht Acute Stress Test) or a standardized control protocol. Successful stress induction in the stress group compared to the no-stress group was confirmed by increased salivary cortisol, an indicator of stress-related hypothalamus-pituitaryadrenal axis activity, throughout the event-based PM tasks. Nevertheless, not-only PM-cue identification but also output monitoring remained fully intact after stress induction. The absence of these effects was independent of ongoing-task demands. Nonetheless, we replicated recent findings of a stress-induced reduction in performance cost of monitoring for PM-cue occurrences. Taken together our findings suggest that acute stress alters PM monitoring by enhancing selective attention, decreasing PM response thresholds or by shifting performance towards more automatic processes in PM, while not affecting PM-cue identification and output monitoring.

From words to action: Implicit attention to antisocial semantic cues predicts aggression and amygdala reactivity to angry faces in healthy young women

Implicit measures of aggressiveness are able to circumvent response biases that plague self-reports, but it is unclear how they link to neural activation during aggressive interactions and to aggression-related endocrine function. Here, we tested whether an implicit attentional bias toward antisocial semantic information was associated with endogenous testosterone (T) and cortisol (C) levels, as well as with aggressive behavior and amygdala reactivity to angry faces in a separate competitive paradigm. On Day one, participants (39 healthy young women) completed an emotional word Stroop task in which they had to indicate the font color of antisocial, prosocial, or neutral words. On Day two, we measured subjects' brain activity during a competitive reaction time task in which the female opponent displayed angry or neutral facial expressions at the start of each trial and provoked participants with increasingly strong sound blasts. T and C were measured in saliva during a regular weekday as well as before and after scanning. We previously showed that aggression was associated with enhanced amygdala reactivity to angry faces in this sample. The present analyses revealed that subjects were slower to identify the font color of antisocial relative to neutral words, and that this attentional bias predicted higher aggression. T and C were uncorrelated with Stroop scores. Crucially, the relationship between implicit attention to antisocial words and aggression was mediated by amygdala reactivity to angry faces. Our data indicate that a tendency to dwell on implicit hostile cues reflects enhanced responsivity to overt anger displays.

Model-based learning and individual differences in depression: The moderating role of stress

Inflexible decision-making has been proposed as a transdiagnostic risk factor for mood disorders. Evidence suggests that inflexible decision-making may emerge only when individuals are experiencing increased negative affect or stress. 151 participants completed symptom measures of depression and anxiety, followed by a two-stage decision-making task that distinguishes between habitual and goal-directed choice. An experimental manipulation to induce stress was introduced halfway through the task. Individuals with higher depression levels became less model-based after the manipulation than those with lower depression levels. There was no relationship between trait anxiety and the impact of the manipulation on decision-making. Controlling for main effects of anxiety did not attenuate the association between depression and impact of stress. Anhedonia was associated with the impact of the manipulation on model-based decision-making. These results suggest that risk for depression is associated with reflexive decision-making, but these effects may only emerge under conditions of stress.

A laboratory study on attentional bias as an underlying mechanism affecting the link between cortisol and performance, leading to a discussion on the nature of the stressor (artificial vs. psychosocial)

Although cortisol is assumed to influence performance by affecting cognition during stressful and competitive situations, to date this assumption has not been tested empirically. Therefore, the aim of this study was to investigate whether the influence of cortisol on performance is mediated by attentional processing of emotional information. Forty-six male golfers were tested in a mixed design. The cold pressor task (CPT) was used to artificially increase cortisol levels in the experimental group relative to the control group, who had to put their forearm in warm water. Before and after water immersion the golfers performed one-armed 1.5-m puts and completed the Sport Emotional Stroop Task. Cortisol was significantly increased in the experimental group (CPT). Further, a significant decrease in attentional bias toward negative sport words was detected in the CPT group. However, no changes in putting performance due to an increase in cortisol were observed in the CPT group. Regarding the cortisol-performance relationship, the nature of the stressor (i.e., artificial vs. psychosocial) seems to play a role, as no connection was found in this study using an artificial stressor, whereas previous research using a psychosocial stressor (e.g., an actual competition) did find a connection. On the basis of these results I cautiously conclude that the subjective appraisal of a stressor, which is arguably higher for a psychosocial stressor, is more relevant for sport performance than just a change in cortisol level. However, as the stress response is psychophysiological in nature, future research should continue to investigate the role of cortisol.

The influence of occupational heat exposure on cognitive performance and blood level of stress hormones: a field study report

INTRODUCTION

This article aimed to investigate the effect of heat stress on cognitive performance and the blood concentration of stress hormones among workers of a foundry plant.

METHODS

Seventy workers within the exposed (35 people) and unexposed (35 people) groups were studied. The wet bulb globe temperature (WBGT) index was measured for heat stress assessment. The cognitive performance tests were conducted using the Stroop color word test (SCWT) before and during working hours. For the assessment of the serum level of cortisol and the plasma level of adrenaline and noradrenaline, blood samples were taken during working hours from both groups.

RESULTS

Only for SCWT III was there a significant relationship between heat stress and test duration, error rate and reaction time. The laboratory test results revealed significantly higher concentrations of cortisol, adrenaline and noradrenaline in the exposed subjects than in the unexposed group. There existed a positive correlation between cortisol, adrenaline, noradrenaline and WBGT index and also test duration and reaction time of SCWT III, and number of errors of SCWT I, SCWT II and SCWT III during work.

CONCLUSION

Heat stress can lead to an increase in the blood level of stress hormones, resulting in cognitive performance impairment.

Selective attention to emotional cues and emotion recognition in healthy subjects: the role of mineralocorticoid receptor stimulation

RATIONALE

Selective attention toward emotional cues and emotion recognition of facial expressions are important aspects of social cognition. Stress modulates social cognition through cortisol, which acts on glucocorticoid (GR) and mineralocorticoid receptors (MR) in the brain.

OBJECTIVES

We examined the role of MR activation on attentional bias toward emotional cues and on emotion recognition.

METHODS

We included 40 healthy young women and 40 healthy young men (mean age 23.9 ± 3.3), who either received 0.4 mg of the MR agonist fludrocortisone or placebo. A dot-probe paradigm was used to test for attentional biases toward emotional cues (happy and sad faces). Moreover, we used a facial emotion recognition task to investigate the ability to recognize emotional valence (anger and sadness) from facial expression in four graded categories of emotional intensity (20, 30, 40, and 80 %).

RESULTS

In the emotional dot-probe task, we found a main effect of treatment and a treatment × valence interaction. Post hoc analyses revealed an attentional bias away from sad faces after placebo intake and a shift in selective attention toward sad faces compared to placebo. We found no attentional bias toward happy faces after fludrocortisone or placebo intake. In the facial emotion recognition task, there was no main effect of treatment.

CONCLUSIONS

MR stimulation seems to be important in modulating quick, automatic emotional processing, i.e., a shift in selective attention toward negative emotional cues. Our results confirm and extend previous findings of MR function. However, we did not find an effect of MR stimulation on emotion recognition.

Prednisolone increases neural reactivity to negative socio-emotional stimuli in healthy young men

Exogenous glucocorticoids are known to trigger affective changes, but these are highly variable across individuals. A better understanding of how synthetic glucocorticoids impact the processing of negative emotions in the human brain might help to predict such changes. In the present functional magnetic resonance imaging (fMRI) study, we sought to uncover the slow effects of a synthetic glucocorticoid infusion on the neural response to socio-emotional scenes using a within-participant, double-blind, placebo-controlled design. In two separate sessions, 20 young males were given either an intravenous prednisolone dose (250mg) or placebo in a cross-over, randomized order. Four hours later, they were scanned while viewing drawings of persons in a neutral or negative emotional situation. On the next morning participants provided a blood sample for serum cortisol measurement, which served as a manipulation check. Prednisolone strongly suppressed morning cortisol, and heightened brain reactivity to emotional stimuli in left amygdala, left caudate head, right inferior frontal gyrus, bilateral supplementary motor area, and right somatosensory cortex. Amygdala reactivity was related to lower self-reported fatigue and higher irritability in the prednisolone condition. Moreover, prednisolone blunted inferior frontal and amygdala connectivity with other regions of the emotion-processing neural circuitry. Our results suggest specific brain pathways through which exogenous glucocorticoids may labilize affect.

Effects of Socioeconomic Status and Fairness on Salivary Cortisol

Research on cooperation has contributed to a better understanding of the foundations of human social behavior. Most studies, however, have not considered fundamental social parameters such as an individual’s position in a social hierarchy. As a first step, this study investigates the modulating effects of socioeconomic status (SES) on behavior and the physiological stress response. Study participants ( n = 83) played a cooperative game with computerized coplayers of four categories: similar or higher SES in combination with either high or low fairness in behavior (i.e., willingness to cooperate). All participants showed a significant increase in saliva cortisol after the game compared to a control group. Only when paired with higher SES coplayers, however, did participants show a significant subsequent decrease in cortisol concentrations. Participants’ behavior in response to a coplayer’s decisions was only affected by the degree of fairness, but not the SES, of respective coplayers. Physiologically, playing this cooperation game was a big challenge for participants as measured by salivary cortisol. Yet, the high recovery rate when playing with cooperative, higher status individuals showed the stress-protective effects of positive social interactions in the framework of social hierarchies.

Routine handling methods affect behaviour of three-spined sticklebacks in a novel test of anxiety

Fish are increasingly popular subjects in behavioural and neurobiological research. It is therefore important that they are housed and handled appropriately to ensure good welfare and reliable scientific findings, and that species-appropriate behavioural tests (e.g. of cognitive/affective states) are developed. Routine handling of captive animals may cause physiological stress responses that lead to anxiety-like states (e.g. increased perception of danger). In fish, these may be particularly pronounced when handling during tank-to-tank transfer involves removal from water into air. Here we develop and use a new combined scototaxis (preference for dark over light areas) and novel-tank-diving test, alongside conventional open-field and novel-object tests, to measure the effects of transferring three-spined sticklebacks (Gasterosteus aculeatus) between tanks using a box or net (in and out of water respectively). Preference tests for dark over light areas confirmed the presence of scototaxis in this species. Open-field and novel-object tests failed to detect any significant differences between net and box-handled fish. However, the combined diving and scototaxis detected consistent differences between the treatments. Net-handled fish spent less time on the dark side of the tank, less time in the bottom third, and kept a greater distance from the 'safe' bottom dark area than box-handled fish. Possible explanations for this reduction in anxiety-like behaviour in net-handled fish are discussed. The combined diving and scototaxis test may be a sensitive and taxon-appropriate method for measuring anxiety-like states in fish.

Effects of intranasal oxytocin on steroid hormones in men and women

BACKGROUND

Recent interest in the social and cognitive effects of intranasal oxytocin prompts a need for understanding its physiological effects in humans. Few studies have examined the effects of intranasal oxytocin on steroid hormones. Filling this gap is especially important given the evidence that steroid hormones participate in some of the same behavioral functions as oxytocin, e.g. in stress, processing of emotional stimuli, aggression, trust, empathy, and parental care.

METHODS

In randomized, double-blind experiments, we administered oxytocin (24 IU) or saline placebo to 97 healthy participants. Saliva samples were collected before and at several time points after the oxytocin/placebo administration to assess the levels of cortisol, progesterone, and testosterone.

RESULTS

Oxytocin had no effects on testosterone, progesterone, or cortisol in women or men.

CONCLUSION

Acute intranasal oxytocin does not affect the levels of cortisol, testosterone or progesterone in humans, at least in the absence of a stressful context. These data suggest that acute oxytocin does not have a direct impact on the human hypothalamic-pituitary-adrenal or hypothalamic-pituitary-gonadal axes under nonstressful circumstances. This knowledge helps rule out potential mechanisms for some of the effects of oxytocin in humans and adds to the generally limited body of knowledge on the basic physiological or psychological effects of intranasal oxytocin in human beings.

Perceived control alters the effect of acute stress on persistence

We often encounter setbacks while pursuing our goals. Success requires that we cope with these negative outcomes and choose to persist in spite of them. For example, learners may be more likely to continue a course after failing an assessment if they control their emotional reactions to the setback and study harder. However, the ability to effectively cope with the negative emotion inherent in such setbacks can be compromised by acute stress present in daily life (e.g., struggles in the household), which can subsequently lead to problems with persisting with a goal. The present study examined whether increasing the perception of control over setbacks (e.g., belief that a setback was caused by a correctable mistake rather than uncontrollable factors) can guard against the influence of a prior acute stressor on reactions to setbacks. Participants underwent a socially evaluated cold water stress or a nonstress control procedure. Afterward, they performed a behavioral task designed to measure persistence through controllable and uncontrollable setbacks. We observed that exposure to an acute stressor led to a detrimental effect on decision making by decreasing persistence behavior. Importantly, we also observed that the perception of control protected against the effect of preexisting stress and helped promote persistence. That is, stress impaired persistence through uncontrollable setbacks, but the impairment was alleviated by presenting setbacks as controllable. The findings demonstrate a potential avenue for improving the maintenance of goals aimed at behavior change, which can be susceptible to effects of stress.

Dissociated neural effects of cortisol depending on threat escapability

Evolution has provided us with a highly flexible neuroendocrine threat system which, depending on threat imminence, switches between active escape and passive freezing. Cortisol, the "stress-hormone", is thought to play an important role in both fear behaviors, but the exact mechanisms are not understood. Using pharmacological functional magnetic resonance imaging we investigated how cortisol modulates the brain's fear systems when humans are under virtual-predator attack. We show dissociated neural effects of cortisol depending on whether escape from threat is possible. During inescapable threat cortisol reduces fear-related midbrain activity, whereas in anticipation of active escape cortisol boosts activity in the frontal salience network (insula and anterior cingulate cortex), which is involved in autonomic control, visceral perception and motivated action. Our findings suggest that cortisol adjusts the human neural threat system from passive fear to active escape, which illuminates the hormone's crucial role in the adaptive flexibility of fear behaviors.

Cortisol and testosterone increase financial risk taking and may destabilize markets

It is widely known that financial markets can become dangerously unstable, yet it is unclear why. Recent research has highlighted the possibility that endogenous hormones, in particular testosterone and cortisol, may critically influence traders’ financial decision making. Here we show that cortisol, a hormone that modulates the response to physical or psychological stress, predicts instability in financial markets. Specifically, we recorded salivary levels of cortisol and testosterone in people participating in an experimental asset market (N = 142) and found that individual and aggregate levels of endogenous cortisol predict subsequent risk-taking and price instability. We then administered either cortisol (single oral dose of 100 mg hydrocortisone, N = 34) or testosterone (three doses of 10 g transdermal 1% testosterone gel over 48 hours, N = 41) to young males before they played an asset trading game. We found that both cortisol and testosterone shifted investment towards riskier assets. Cortisol appears to affect risk preferences directly, whereas testosterone operates by inducing increased optimism about future price changes. Our results suggest that changes in both cortisol and testosterone could play a destabilizing role in financial markets through increased risk taking behaviour, acting via different behavioural pathways.

In the face of threat: neural and endocrine correlates of impaired facial emotion recognition in cocaine dependence

The ability to recognize facial expressions of emotion in others is a cornerstone of human interaction. Selective impairments in the recognition of facial expressions of fear have frequently been reported in chronic cocaine users, but the nature of these impairments remains poorly understood. We used the multivariate method of partial least squares and structural magnetic resonance imaging to identify gray matter brain networks that underlie facial affect processing in both cocaine-dependent (n = 29) and healthy male volunteers (n = 29). We hypothesized that disruptions in neuroendocrine function in cocaine-dependent individuals would explain their impairments in fear recognition by modulating the relationship with the underlying gray matter networks. We found that cocaine-dependent individuals not only exhibited significant impairments in the recognition of fear, but also for facial expressions of anger. Although recognition accuracy of threatening expressions co-varied in all participants with distinctive gray matter networks implicated in fear and anger processing, in cocaine users it was less well predicted by these networks than in controls. The weaker brain-behavior relationships for threat processing were also mediated by distinctly different factors. Fear recognition impairments were influenced by variations in intelligence levels, whereas anger recognition impairments were associated with comorbid opiate dependence and related reduction in testosterone levels. We also observed an inverse relationship between testosterone levels and the duration of crack and opiate use. Our data provide novel insight into the neurobiological basis of abnormal threat processing in cocaine dependence, which may shed light on new opportunities facilitating the psychosocial integration of these patients.

Cortisol administration induces global down-regulation of the brain's reward circuitry

Research in rodents and humans has shown divergent effects of the glucocorticoids corticosterone and cortisol (CRT) on reward processing. In rodents, administration of CRT increases reward drive by facilitating dopamine release in the ventral striatum. In humans, correspondingly, risky decision-making increases when CRT levels are elevated. Human stress studies contrariwise show that elevated CRT is accompanied by a decrease in reward-related brain activity. There are however no direct insights into how CRT acts on the reward system in the human brain. Accordingly, we used pharmacological functional magnetic resonance imaging (pharmaco-fMRI) to investigate the effects of CRT on the brain's reward system. In a randomized within-subject design we administered a high dose of CRT (40 mg) and placebo to twenty healthy male volunteers on separate days, and used a monetary incentive delay task to assess the effects of the hormone on the striatum and the amygdala in anticipation of potential reward. In contrast to animal studies, we show that this high dose of CRT strongly decreases activity of the striatum in both reward and non-reward conditions. Furthermore, we observed reductions in activity in the basolateral amygdala, a key regulator of the brain's reward system. Crucially, the overall down-regulation of the brain's reward circuit was verified on the subjective level as subjects reported significantly reduced reward preference after CRT. In sum, we provide here direct evidence in humans that CRT acts on brain regions involved in reward-related behavior, that is, the basolateral amygdala and the striatum. Our findings suggest that CRT in the quantity and time course presently used globally down-regulates the reward system, and thereby decreases motivational processing in general.

Enhanced orienting of attention in response to emotional gaze cues after oxytocin administration in healthy young men

BACKGROUND

Oxytocin is known to enhance recognition of emotional expressions and may increase attention to the eye region. Therefore, we investigated whether oxytocin administration would lead to increased orienting of attention in response to gaze cues of emotional faces.

METHODS

In a randomized placebo-controlled double-blind crossover study 20 healthy males received 24 IU of oxytocin or placebo. Thirty-five minutes after administration they performed a gaze cueing task with happy, fearful and neutral faces. Stress levels were measured throughout the study.

RESULTS

Oxytocin did not affect stress levels during the study, but significantly increased gaze cueing scores for happy and fearful expressions compared to placebo. No effects were found for neutral expressions. Trait anxiety or depression did not moderate the effect.

CONCLUSIONS

Oxytocin increases orienting of attention in response to emotional gaze cues, both for happy and fearful expressions. Replication is needed in female and clinical populations. Effects of oxytocin on early, automatic processing levels should be studied in relation to previously found pro-social and behavioral effects of oxytocin.

Assessing the relationship between rumination and cortisol: a review

OBJECTIVE AND METHODS

For individuals who ruminate, or mentally rehearse past stressful events, the physiological effects of a stressor may be longer lasting. This is well-supported within the cardiovascular domain. In the context of the hypothalamic-pituitary-adrenal (HPA) axis and cortisol, the results are inconsistent. This review summarizes key theoretical and methodological issues that contribute to these mixed findings among the 15 studies to date that have examined the association between rumination and cortisol.

RESULTS

State measures of rumination were consistently linked to increased cortisol concentrations. Stress-related rumination questionnaires were often positively associated with cortisol, whereas depression-related rumination scales predicted lower cortisol concentrations or were unrelated to cortisol. Rumination manipulations in the laboratory (e.g., ruminative self-focused writing tasks compared to distraction writing tasks) influenced cortisol concentrations, but often did not increase cortisol relative to baseline values. Studies that utilized social-evaluative stressor tasks to examine the relationship between rumination and cortisol levels generally showed that rumination predicted greater cortisol reactivity or delayed recovery. Results from studies examining rumination and basal cortisol or the cortisol awakening response were inconsistent.

CONCLUSION

The ways in which researchers conceptualize and assess rumination and the associated cortisol response influences the association between rumination and cortisol. Suggestions for future studies in this area of research are provided.

Dose-dependent effects of hydrocortisone infusion on autobiographical memory recall

The glucocorticoid hormone cortisol has been shown to impair episodic memory performance. The present study examined the effect of two doses of hydrocortisone (synthetic cortisol) administration on autobiographical memory retrieval. Healthy volunteers (n = 66) were studied on two separate visits, during which they received placebo and either moderate-dose (0.15 mg/kg IV; n = 33) or high-dose (0.45 mg/kg IV; n = 33) hydrocortisone infusion. From 75 to 150 min post-infusion subjects performed an Autobiographical Memory Test and the California Verbal Learning Test (CVLT). The high-dose hydrocortisone administration reduced the percent of specific memories recalled (p = .04), increased the percent of categorical (nonspecific) memories recalled (p < .001), and slowed response times for categorical memories (p < .001), compared with placebo performance. Under moderate-dose hydrocortisone the autobiographical memory performance did not change significantly with respect to percent of specific or categorical memories recalled or reaction times. Performance on the CVLT was not affected by hydrocortisone. These findings suggest that cortisol affects accessibility of autobiographical memories in a dose-dependent manner. Specifically, administration of hydrocortisone at doses analogous to those achieved under severe psychosocial stress impaired the specificity and speed of retrieval of autobiographical memories.

In the eye of the beholder: reduced threat-bias and increased gaze-imitation towards reward in relation to trait anger

The gaze of a fearful face silently signals a potential threat's location, while the happy-gaze communicates the location of impending reward. Imitating such gaze-shifts is an automatic form of social interaction that promotes survival of individual and group. Evidence from gaze-cueing studies suggests that covert allocation of attention to another individual's gaze-direction is facilitated when threat is communicated and further enhanced by trait anxiety. We used novel eye-tracking techniques to assess whether dynamic fearful and happy facial expressions actually facilitate automatic gaze-imitation. We show that this actual gaze-imitation effect is stronger when threat is signaled, but not further enhanced by trait anxiety. Instead, trait anger predicts facilitated gaze-imitation to reward, and to reward compared to threat. These results agree with an increasing body of evidence on trait anger sensitivity to reward.

Stress increases the feeling of being looked at

Eye gaze direction and facial expression are important social cues. Recent studies have shown that emotional expression affects interpretation of gaze direction in such a way that positive emotions are more favorably interpreted as making eye contact than negative or neutral expressions. Here we examine whether stress affects this positivity bias in gaze perception. Stress was induced in 25 healthy young adults by means of the cold pressure stress test (CPS), 24 participants serving as controls. Stimuli were created from three-dimensional face models of 8 actors expressing happy, fearful, angry and neutral emotions. From each of these 3D models we extracted 9 different views (0°, 2°, 4°, 6° and 8° to the left and to the right). This resulted in 288 stimuli, which were randomly presented for 700 ms. Using a forced choice paradigm participants judged whether or not each face was looking at them. The results show that the CPS group falsely interpreted faces with averted gaze direction as making eye contact more often than did controls, independent of the expressed emotion. These results suggest that a stress-induced raise in cortisol level increases the sense of being looked at.

Stress-induced cortisol level elevations are associated with reduced negative affect after stress: indications for a mood-buffering cortisol effect

OBJECTIVE

Stress is associated with increased negative affect and activation of the sympathetic nervous system and of the hypothalamic-pituitary-adrenal axis. However, the relationship between these stress systems and negative affect is incompletely understood. We therefore investigated positive and negative affects in relationship with salivary cortisol and salivary α-amylase (sAA) levels in a large sample of participants exposed to a psychosocial stressor or a control condition.

METHODS

Cortisol and sAA levels from five studies with a total sample size of 232 participants were reanalyzed using hierarchical linear modeling. In these studies, we measured affective responses to the Trier Social Stress Test (TSST) and its control condition (placebo TSST) with the Positive and Negative Affect Schedule.

RESULTS

An inverse relationship between cortisol and negative affect was observed across all participants (β(06) = -0.13, p = .002). Higher level of negative affect was associated with lower mean cortisol levels 10 minutes after the TSST or the control condition. When the two conditions were tested separately, the effect was significant in the stress condition (β(06) = -0.05, p = .02) but not in the control condition (β(06) = -0.0008, p > .05). In contrast to the results for cortisol, a positive relationship was found between sAA and negative affect within the stress condition (β(06) = 0.10, p = .005).

CONCLUSIONS

The present findings suggest that cortisol is associated with an attenuated negative emotional arousal in response to acute stress, whereas sAA levels seem to reflect the degree of negative emotional arousal. Together with previous pharmacological studies, these data seem to support the hypothesis of mood-buffering effects of cortisol.

Testosterone, cortisol, and serotonin as key regulators of social aggression: A review and theoretical perspective

In human and non-human animals the steroid hormones cortisol and testosterone are involved in social aggression and recent studies suggest that these steroids might jointly regulate this behavior. It has been hypothesized that the imbalance between cortisol and testosterone levels is predictive for aggressive psychopathology, with high testosterone to cortisol ratio predisposing to a socially aggressive behavioral style. In this review, we focus on the effects of cortisol and testosterone on human social aggression, as well as on how they might modulate the aggression circuitry of the human brain. Recently, serotonin is hypothesized to differentiate between impulsive and instrumental aggression, and we will briefly review evidence on this hypothesis. The aim of this article is to provide a theoretical framework for the role of steroids and serotonin in impulsive social aggression in humans.

Cortisol acutely reduces selective attention for erotic words in healthy young men

Psychological stress prompts activity of the hypothalamic-pituitary-adrenal (HPA) axis resulting in increased release of cortisol. Long-term HPA aberrations have been observed for stress-related affective disorders but research into acute effects of cortisol on affect-regulation has only recently begun. Previous studies reported that exogenous cortisol acutely attenuated automatic attentional processing of task-irrelevant threatening information. This has been taken to suggest that cortisol may have acute anxiolytic properties, possibly through facilitating inhibition of threatening information. However, the role of cortisol in attentional inhibition of non-threatening arousing stimuli remained unclear. Therefore acute effects of 40 mg cortisol on performance of a masked and unmasked emotional Stroop task (EST) were assessed. Results for only the unmasked task demonstrated EST interference (interpreted as increased automatic attention) for erotic stimuli which was abolished by cortisol administration. This implies that effects of cortisol may not be restricted to attenuation of specifically anxiogenic information processing, as previously suggested.

The effect of cortisol on emotional responses depends on order of cortisol and placebo administration in a within-subject design

Cortisol does not exhibit a straightforward relationship with mood states; administration of glucocorticoids to human subjects has produced mixed effects on mood and emotional processing. In this study, participants (N=46) received intravenous hydrocortisone (synthetic cortisol; 0.1mg/kg body weight) and placebo in randomized order over two sessions 48h apart. Following the infusion, participants rated neutral and unpleasant pictures. In Session 1, participants reported elevated negative affect (NA) following the picture-rating task, regardless of treatment. In Session 2, however, only participants who received cortisol (and thus who had received placebo in Session 1) reported elevated NA. Arousal ratings for unpleasant pictures followed a similar pattern. These findings suggest that the effects of cortisol on emotion vary based on situational factors, such as drug administration order or familiarity with the tasks and setting. Such factors can influence cortisol's effects on emotion in two ways: (A) cortisol may only potentiate NA and arousal ratings in the absence of other, overwhelming influences on affect, such as the novelty of the setting and tasks in Session 1; and (B) cortisol in Session 1 may facilitate learning processes (e.g., habituation to the stimuli and setting; extinction of aversive responses) such that emotional responses to the pictures are lessened in Session 2. This interpretation is compatible with a body of literature on the effects of glucocorticoids on learning and memory processes.

Effects of single cortisol administrations on human affect reviewed: Coping with stress through adaptive regulation of automatic cognitive processing

The human stress hormone cortisol may facilitate effective coping after psychological stress. In apparent agreement, administration of cortisol has been demonstrated to reduce fear in response to stressors. For anxious patients with phobias or posttraumatic stress disorder this has been ascribed to hypothetical inhibition of retrieval of traumatic memories. However, such stress-protective effects may also work via adaptive regulation of early cognitive processing of threatening information from the environment. This paper selectively reviews the available literature on effects of single cortisol administrations on affect and early cognitive processing of affectively significant information. The concluded working hypothesis is that immediate effects of high concentration of cortisol may facilitate stress-coping via inhibition of automatic processing of goal-irrelevant threatening information and through increased automatic approach-avoidance responses in early emotional processing. Limitations in the existing literature and suggestions for future directions are briefly discussed.

Exogenous cortisol facilitates responses to social threat under high provocation

Stress is one of the most important promoters of aggression. Human and animal studies have found associations between basal and acute levels of the stress hormone cortisol and (abnormal) aggression. Irrespective of the direction of these changes--i.e., increased or decreased aggressive behavior--the results of these studies suggest dramatic alterations in the processing of threat-related social information. Therefore, the effects of cortisol and provocation on social information processing were addressed by the present study. After a placebo-controlled pharmacological manipulation of acute cortisol levels, we exposed healthy individuals to high or low levels of provocation in a competitive aggression paradigm. Influences of cortisol and provocation on emotional face processing were then investigated with reaction times and event-related potentials (ERPs) in an emotional Stroop task. In line with previous results, enhanced early and later positive, posterior ERP components indicated a provocation-induced enhanced relevance for all kinds of social information. Cortisol, however, reduced an early frontocentral bias for angry faces and--despite the provocation-enhancing relevance--led to faster reactions for all facial expressions in highly provoked participants. The results thus support the moderating role of social information processing in the 'vicious circle of stress and aggression'.

Glucocorticoid augmentation of prolonged exposure therapy: rationale and case report

RATIONALE

Prolonged exposure (PE) therapy has been found to reduce symptoms of posttraumatic stress disorder (PTSD); however, it is difficult for many patients to engage fully in the obligatory retelling of their traumatic experiences. This problem is compounded by the fact that habituation and cognitive restructuring - the main mechanisms through which PE is hypothesized to work - are not instantaneous processes, and often require several weeks before the distress associated with imaginal exposure abates.

CASE REPORTS

Two cases are described that respectively illustrate the use of hydrocortisone and placebo, in combination with PE, for the treatment of combat-related PTSD. Based on known effects of glucocorticoids on learning and memory performance, we hypothesized that augmentation with hydrocortisone would improve the therapeutic effects of PE by hastening "new" learning and facilitating decreases in the emotional impact of fear memories during the course of treatment. The veteran receiving hydrocortisone augmentation of PE displayed an accelerated and ultimately greater decline in PTSD symptoms than the veteran receiving placebo.

CONCLUSIONS

While no general conclusion can be derived from comparison of two patients, the findings are consistent with the rationale for augmentation. These case reports support the potential for an appropriately designed and powered clinical trial to examine the efficacy of glucocorticoids in augmenting the effects of psychotherapy for PTSD.

Exogenous cortisol acutely influences motivated decision making in healthy young men

BACKGROUND

The glucocorticoid (GC) hormone cortisol is the end product of the hypothalamic-pituitary-adrenal axis (HPA axis). Acute psychological stress increases HPA activity and GC release. In humans, chronic disturbances in HPA activity have been observed in affective disorders and in addictive behaviour. Recent research indicates that acute effects of GCs may be anxiolytic and increase reward sensitivity. Furthermore, cortisol acutely influences early cognitive processing of emotional stimuli.

METHODS

In order to extend such findings to more complex emotional-cognitive behaviour, the present study tested acute effects of 40 mg cortisol on motivated decision making in 30 healthy young men.

RESULTS

Results showed that cortisol indeed increased risky decision making, as predicted. This effect occurred for decisions where making a risky choice could potentially yield a big reward. These results are discussed with respect to currently proposed mechanisms for cortisol's potential anxiolytic effect and GCs' involvement in reward systems.