Oliver T Wolf

..At the end, the concept of allostatic load (AL) is described, which aims at a broader assessment of the impact of stress on the individual. The strengths and also the current limitations of the AL concept are highlighted...

..The findings presented are in line with models derived from experiments in rodents and are of relevance for our understanding of stress associated psychiatric disorders...

..The present study indicates that an immediate retrieval attempt of material studied after stress exposure can prevent or even reverse the beneficial effects of pre-encoding stress on emotional long-term memory consolidation...

..Controls, in contrast, acquired the discrimination rapidly. The present study provides further evidence for an impairing effect of acute stress on tasks relying on the hippocampal formation...

..Our findings indicate that acute stress, possibly via activation of the hypothalamus-pituitary-adrenal (HPA) axis, reduces the ability to acquire a simple conditioned motor response in humans...

..The shift toward "procedural" learning after stress appears to rescue task performance, whereas attempts to engage the "declarative" system disrupt performance...

..These results demonstrate the importance of stress-induced hormone-related activity in enhancing memory consolidation and in impairing memory retrieval, in particular for emotional memory material...

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..These findings show a memory impairing effect of learning under stress in humans and challenge some assumptions of current theories about the impact of stress around the time of learning on memory formation...

..e., habitual). These findings demonstrate that the concerted action of glucocorticoids and noradrenergic activity shifts instrumental behavior from goal-directed to habitual control...

..Thus, in contrast to previous studies, post-learning stress primarily enhanced consolidation of neutral material. Several theoretical and methodological explanations for the observed effects are discussed...

..These findings show that stress induced by the socially evaluated cold pressor test can make behavior habitual without affecting processes involved in learning...

..Moreover this effect seems to be modulated by encoding instructions, suggesting a role of focussed attention or arousal induced by testing in this relationship...

..Evidence is discussed that the luteal phase, which is characterized by elevated gonadal steroids, is associated with reduced glucocorticoid sensitivity. This might underlie the missing impact of stress on memory...

..These findings suggest that concurrent glucocorticoid and noradrenergic activity disrupts the neural bases of goal-directed action and thus renders behavior habitual...

..Stress administered prior to encoding abolished the context-dependent memory enhancement found in the control group. Thus, these findings represent the first demonstration of impaired context-dependent memory following stress...

..Our findings show that the shift from goal-directed to habitual control of instrumental action under stress necessitates noradrenergic activation and could have important clinical implications, particularly for addictive disorders...

..Moreover, stress reduced subjects' explicit knowledge of the action-outcome contingencies. These results demonstrate for the first time that stress promotes habits at the expense of goal-directed performance in humans...

..However, neither stress nor cortisol interacted with the emotionality of the target words. In summary, these findings point to a strong impact of emotional factors on early perceptual experiences...

..Individual differences in acute or chronic stress do not account for these findings. Our data suggest that the engagement of hippocampal and nonhippocampal learning strategies may be influenced by stress very early in life...

..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...

..In line with several previous studies the findings might suggest that stress-induced changes in gonadal steroids occur in response to physical stressors, to competitive stressors or to more severe stressors only...

..The suggested mechanism encompasses cognitive processes that may contribute to the effects of stress on addictive behavior and could have important implications for the treatment of addiction and the prevention of relapse...

..These results suggest that the detrimental effects of stress on memory retrieval can be abolished when a distinct learning context is reinstated at test...

..These results suggest that new learning impedes the reconsolidation of neutral autobiographical memories...

..Although generally adaptive, these changes in the control of instrumental action under stress may promote dysfunctional behaviors and the development of psychiatric disorders such as addiction...

..These findings appear to support the idea that social-evaluative threat is an important factor determining the size of the HPA response to laboratory stressors as well as to real-life stressors...

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..Thus, the effects of stress became smaller the longer the task was performed. Results provide further evidence for impaired working memory after acute stress and illustrate the time course of this phenomenon...

..These results indicate that acute stress impairs WM performance for tasks requiring executive functions that operate on the stored material but not for WM tasks that only require maintenance...

..These findings suggest that the effect of stress on memory reconsolidation is opposite to the stress effect on memory consolidation supporting the view that consolidation and reconsolidation are distinct processes...

..These findings show that retrieval and interference have opposite effects on memory that depend on the remoteness of the memories and raise the question under which conditions reconsolidation effects occur in human memory...

..Overall learning curves remained unaffected. Thus, the present findings suggest that stress increases the resistance of behavior to extinction. The cause of the behavioral persistence after stress may be its habitual form...

..Here, we review stress effects on both quantity and quality of memory and address possible implications of these effects for the understanding of stress-related psychiatric disorders...

..These effects might translate into a different vulnerability of the two sexes for anxiety disorders...

..These sex differences may represent a biological mechanism that contributes to the differential prevalence of fear-related disorders in men and women...

..These findings may have important implications for novel treatment approaches that aim for modification of unwanted memories during reconsolidation...

..On a conceptual level our data indicate that mere social performance in the absence of social-evaluative threat and performance pressure does not activate the HPA axis...

..We argue that, despite being generally adaptive, this stress-induced shift towards 'habit' memory may, in vulnerable individuals, be a risk factor for psychopathology...

..In contrast to long-term memory, the influence of stress on WM appears not to be modulated by the emotionality of the employed stimuli if stimuli are potential targets as it is the case in the n-back task...

..Here, we asked whether a β-adrenergic receptor antagonist might interfere with the reconsolidation of emotional episodic memories and what brain mechanisms are involved in these effects...

..It remains possible that age-associated changes in fast feedback may be related to changes to other brain sites, such as hypothalamus or pituitary...

..Differences in personality traits or in stress susceptibility might underlie the present findings. Future studies of memory complaints should take a comprehensive approach including relevant endocrine parameters...

..Among them is the small sample size, the moderate cortisol increase in response to the second stress exposure but also the long recall delay, which might lead to memory traces less susceptible to stress...

..The underlying neurobiological mechanisms of these behavioral findings remain to be elucidated...

..Another objective was to evaluate whether salivary cortisol levels correlated with rCBF in other brain areas...

..In contrast to the positive findings in women endogenous sex steroids do not appear to be closely linked to better cognition in older men...

..Future ERP studies therefore need to be more attentive to the issue of menstrual phase when studying female subjects or female patients...

..The human brain might loose its responsiveness to gonadal steroids with aging or prolonged hormone depletion...

..The present study thus demonstrates that psychosocial stress impairs memory retrieval in humans and suggests that emotionally arousing material is especially sensitive to this effect...

..Results are discussed with regard to the context of specific adaptive effects of cortisol and the role of cortisol in posttraumatic stress disorder...

..There is evidence of both hypothalamic-pituitary-adrenocortical (HPA) axis and cognitive dysfunction in type 2 diabetes mellitus (T2DM). However, the exact nature and the associations between these abnormalities remain unclear...

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..Further studies will be needed to disentangle the complex relationship between depression and the ACR...

..84). The results indicate that the experimental setting can influence the effect of cortisol on memory. Our findings suggest that glucocorticoid effects on memory retrieval require testing-associated arousal in humans...

..No effects of cortisol treatment were observed for recognition memory or mood. Results support the notion that glucocorticoids specifically enhance the consolidation of emotional material...

..Accordingly, the increase of sAA--as an indirect marker of sympathetic nervous system activity--in those patients with less severe decision-making deficits could reflect the use of somatic markers biasing the decision-making process...

..The current pharmacological study in the human provides direct evidence for the sensitivity of sAA to changes in adrenergic activation, specifically in reaction to psychological stress...

..Finally, the relevance of these findings for emotional memory disturbances in psychiatric disorders is exemplified by discussions on neuroendocrine alterations in depression, post traumatic stress disorder and phobias...

..Men had higher sAA levels than women during the complete course of the study, but men and women were comparable in their responsivity to the tasks. No strong correlations between sAA and CORT responses were found...