Stress-induced impairment of fear extinction recall is associated with changes in neuronal activity patterns in PVT.

Treatment resistance of anxiety-related disorders often arises from an inappropriate fear expression, impairment in fear extinction, and spontaneous return of fear. Stress exposure is considered a high risk factor for neuropsychiatric disorders, but understanding of the long-term consequences of stress is limited, particularly when it comes to treatment outcome. Therefore, studying the consequences of acute stress would provide critical information on the role of stress in psychopathology. In the present study, we investigated the effect of acute immobilization stress on anxiety-like behavior and on conditioned fear memory. Our results demonstrate that prior stress exposure had no effect on anxiety-related behavior, fear acquisition, as well as fear extinction compared to non-stressed controls, but resulted in significantly higher rates of freezing during recall of extinction, indicating a consolidation failure. Further, immunohistochemical analysis of the expression of the immediate early gene c-Fos after recall of extinction revealed increased neuronal activity in the posterior paraventricular nucleus of the thalamus (PVT) in previously stressed animals compared to non-stressed controls. These results indicate, firstly, that acute stress affects long-term fear memory even after successful extinction training, and secondly, a strong involvement of the PVT in maladaptive fear responses induced by prior stress. Thus, stress-induced changes in PVT neuronal activity might be of importance for the pathophysiology of stress-sensitive anxiety-related psychiatric disorders, since exposure to an earlier acute stressor could counteract the success of therapy.

Authoritative knowledge and birth territories in contemporary Japan.

In Japan, as in the United States, the change from home to health care institution as the location of birth has been marked by depicting the obstetrician as having authoritative knowledge about birthing. The obstetrician's access to and control over specialized obstetrical technology reflect and legitimate his authoritative status. In Japan a prevailing cultural view of birth as a natural and healthy event places a value on using the least possible amount of obstetrical intervention in the birthing process. This results in the valuation of the potential, rather than the actual, application of obstetrical technology. In contemporary Japan midwives remain integral participants in maternity care and attend normal deliveries in the hospital setting. But because of the culturally depicted potential for pathology at the time of birth, the obstetrician-the birthing specialist who controls the more complex technological tools-is viewed as having greater authoritative knowledge than the midwife and the woman giving birth.