Habituation to repeated stress: get used to it

Habituation, as described in the landmark paper by Thompson et al. [Thompson, R. F., & Spencer, W. A. (1966). Habituation: A model phenomenon for the study of neuronal substrates of behavior. Psychological Review, 73(1), 16–43], is a form of simple, nonassociative learning in which the magnitude of the response to a specific stimulus decreases with repeated exposure to that stimulus. A variety of neuronal and behavioral responses have been shown to be subject to habituation based on the criteria presented in that paper. It has been known for several decades that the magnitude of hypothalamic–pituitary–adrenal (HPA) activation occurring in response to a stressor declines with repeated exposure to that same stressor. For some time this decline has been referred to as “habituation” in the stress neurobiology literature. However, how this usage compares to the definition proposed by Thompson and Spencer has not been systematically addressed. For this special issue, we review the stress neurobiology literature and examine the support available for considering declines in HPA response to repeated stress to be response habituation in the sense defined by Thompson and Spencer. We conclude that habituation of HPA activity meets many, but not all, important criteria for response habituation, supporting the use of this term within the context of repeated stress. However, we also propose that response habituation can, at best, only partially explain the phenomenon of HPA habituation, which also involves well-known negative feedback mechanisms, activation of broad stress-related neural circuitry and potentially more complex associative learning mechanisms.     

Parents as moderators of psychological and physiological correlates of inner-city children's exposure to violence

This paper discusses the psychological and physiological correlates of inner-city violence on children, and the potential mediating and moderating roles of parents. Data are based on interviews regarding exposure to community violence (ECV), parenting practices, child distress, posttraumatic symptomology, and competence. Cardiovascular activation was also measured. Community violence exposure related to distress, posttraumatic symptomology, and incompetence. Harsh parenting related to aggression, distress, incompetence, and higher heart rates. Parenting moderated but did not mediate the effects of violence on measures of competence. High violence plus harsh parenting predicted lower levels of systolic (SBP) and diastolic blood pressure (DBP). Results are discussed within an ecological framework of parent–child relations and as they relate to the conclusion that children undergoing dual levels of stress may experience a dissociative response.     

Perceived stress,life events,dysfunctional attitudes,and depression in adolescent psychiatric inpatients

Hewitt, Flett, and Mosher (1992) examined the factor structure of the Perceived Stress Scale (PSS) and its relation to depression in adult psychiatric patients. This study sought to replicate and extend their findings, using a sample of 203 adolescent psychiatric inpatients. All patients admitted to the adolescent unit in a psychiatric hospital over a 3-year period were administered the PSS, as well as measures of depression, life events, dysfunctional attitudes, and intellectual abilities. Consistent with Hewittet al., two factors were found in the PSS, reflecting perceived distress and perceived coping ability. Regression analyses indicated that, for males, both factors account for independent variance in depression, whereas for females, only the distress factor is related to depression. In addition, for both male and female, dysfunctional attitudes account for significant variance in depression in addition to PSS, but negative life events do not. None of the variables were related to intellectual abilities. Implications for clinical assessment and intervention are discussed.     

Traumatic stress,neural self and the spiritual mind

According to recent findings stressful experiences may influence various physiological disturbances and also neuroanatomical changes and some studies also show that psychotherapy and meditation may influence brain functions. Traumatic stress is frequently related to a dissociative response that disintegrates conscious experience. In this context, self-reflection is an essential principle in the process of posttraumatic growth related to spiritual experiences and meditation states that enable mental integration and create the novel integrated self. According to recent findings there is no widely accepted evidence about specific neural mechanisms of processes related to mental integration linked to the spiritual experiences and meditation. Nevertheless there is growing evidence that these integrative experiences are related to various alterations in the brain’s physiology and morphology. These findings provide a new paradigm for understanding of mental disorders and emphasize the fundamental role of mental integration and integrated self in the therapy of psychiatric disorders.     

冠脉支架术对冠心病患者心理及生活质量的影响

分析冠脉支架术对患者生活质量及心理情况的影响并探讨相应策略。采用横断面研究方法,调查2007年6月-2010年9月在我院行冠脉支架术患者768例,应用Zung焦虑、SAS、SDS自评表及SF-36生活质量问卷等方法采集相关资料,200名健康人为对照1组、未行支架置入的冠心病患者为对照2组,数据行统计学分析。支架植入患者...     

Caudate nucleus-dependent response strategies in a virtual navigation task are associated with lower basal cortisol and impaired episodic memory

The present research examined the relationship between endogenous glucocorticoids, navigational strategies in a virtual navigation task, and performance on standard neuropsychological assessments of memory. Healthy young adult participants (N = 66, mean age: 21.7) were tested on the 4 on 8 virtual maze (4/8 VM) and standard neuropsychological tests such as the Rey-Osterrieth Complex Figure (RO) and the Rey Auditory Verbal Learning Task (RAVLT), which measure episodic memory. The 4/8 VM differentiates between navigational strategies, where participants either use a hippocampal-dependent spatial strategy by building relationships between landmarks, or a caudate nucleus-dependent stimulus–response strategy by automatizing a pattern of open and closed arms to learn the location of objects within the maze. Degree of stress was assessed by administering the Perceived Stress Scale (PSS) questionnaire. Cortisol samples were taken on two consecutive days upon waking, 30 min after waking, at 11 am, 4 pm, and 9 pm. There was a significant difference in basal levels of cortisol between spatial and response learners. Interestingly, response learners had significantly lower cortisol levels throughout the day. The two groups did not differ in terms of perceived stress as measured with the PSS questionnaire. Moreover, there was no significant correlation between PSS scores and salivary cortisol levels, indicating that the higher cortisol levels in the spatial group were not associated with greater perceived stress. In addition, participants who spontaneously used a spatial strategy performed significantly better on the RAVLT and RO. These data indicate that the cortisol levels in the spatial group may be optimal in terms of episodic memory performance whereas the cortisol levels in the response group may be associated with poorer memory. These results are suggestive of an inverted U-shaped curve describing the effects of basal levels of circulating cortisol on memory in young adults.     

The effects of an acute psychosocial stressor on episodic memory

Although stressors are believed to impair memory, experimental studies with humans have provided inconsistent support for this conclusion. The current study was designed to examine the effect of an acute psychosocial stressor, and subsequent reactivity, on episodic memory. One hundred participants completed a list-recall task before and after random assignment into a stressor or nonstressor condition. Participants assigned to the stressor condition exhibited both impaired delayed and immediate recall, and also exhibited increasesin the commission of intrusions and perseverations. The experience of off-task thoughts and intentional suppression of such thoughts, were associated with greater impairment of immediate recall. Changes in state anxiety, negative mood, and heart rate were unrelated to changes in memory. These data indicate that exposure to a stressor impaired the recall of previously learned information, and compromised the recall of newly acquired information. Furthermore, cognitive interference is an important factor regarding stress-related impairments of episodic memory.     

Predicting stress patterns in an unpredictable stress language: The use of non-lexical sources of evidence for stress assignment in Russian

The main goal of this research was to examine how readers of Russian assign stress to disyllabic words. In particular, we tested the claim that the process of stress assignment in Russian can only be accomplished lexically. Eleven potential non-lexical sources of evidence for stress in Russian were examined in regression and factorial studies. In Study 1, onset complexity, coda complexity, the orthography of the first syllable (CVC1), of the second syllable (CVC2), and of the ending of the second syllable (VC2) were found to be probabilistically associated with stress in Russian disyllables. In Studies 2 and 3, it was shown that Russian speakers do use 3 of these cues (CVC1, CVC2, and VC2) when making stress-assignment decisions. These results provide evidence against the idea that the nature of stress in the Russian language is so unpredictable that stress assignment can only be accomplished lexically. These results also suggest that any successful model of stress assignment in Russian needs to contain mechanisms allowing these 3 orthographic cues to play a role in the stress-assignment process.