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151.
To study putative brain circuits involved in habituation to stress, rats were exposed daily (30 min for 15 days) to an environment in the presence (Chronic) or absence (Acute) of loud noise (105 dB sound pressure level--SPL A Scale). Behavioral and endocrine measures of stress were taken throughout this habituation period, and both measures displayed strong habituation in the Chronic group. All rats were killed immediately after the day 16 exposure, constituting an acute stressor for the Acute group, and regional brain activity was assessed using c-fos mRNA induction with in situ hybridization. Hearing damage could not easily explain these results because additional rats exposed to a similar stress protocol exhibited no changes in auditory brainstem evoked potentials. c-fos mRNA induction in the central auditory system was similar between the Acute and Chronic groups, particularly at lower auditory processing levels, also arguing against a simple reduction in auditory processing in the chronically stressed rats. However, c-fos mRNA expression was reduced in chronically, as compared to acutely, stressed rats in several regions previously implicated in audiogenic stress (lateral septum, bed nucleus of the stria terminalis, some preoptic areas, and the paraventricular hypothalamic nucleus). Interestingly, the orbitofrontal cortex was the only region displaying higher c-fos mRNA induction in the chronically as compared to acutely stressed rats. This region has connections to several stress-responsive areas and may thus be a critical region actively inhibiting stress. 相似文献
152.
Jennifer Girod 《The Journal of medical humanities》2002,23(1):31-42
Daniel Callahan's concept of a sustainable medicine is examined by looking at experiences Old Order Amish communities have had with organ and bone marrow transplantation. The Amish possess many characteristics that might make them embrace limits on the use of expensive, life-prolonging medical treatments: they believe that the good of the individual should be subordinated to the good of the community, they are suspicious of progress as a goal, and they are more comfortable with dying than many other modern Americans. However, the Amish actively pursue these treatments without the benefit of private or government insurance. Although the Amish affective response to sick individuals is worthy of emulating, their commitment to help individuals obtain and pay for transplants has had negative financial and cultural effects on some Amish communities. The Amish experience can thus teach us lessons about how to care for one another when we are sick and dying, but it can also teach us how difficult but important it is to limit some forms of expensive care for the good of our communities. 相似文献
153.
This study provides initial psychometric data for the Self-Efficacy Scale (SES) and the Life Orientation Test (LOT) in a sample of older adults with generalized anxiety disorder (GAD). Participants included 76 adults, ages 60 to 80, who met Diagnostic and Statistical Manual of Mental Disorders (4th ed.) criteria for GAD. Self-efficacy and outcome expectancies were lower in older adults with GAD relative to published data from younger and older community samples. Both the SES and LOT demonstrated adequate internal consistency. Confirmatory factor analysis provided evidence for optimism and pessimism factors within the LOT and exploratory factor analysis of the SES suggested threefactors that overlap with previous findings. Overall, the data support the potential utility of these instruments in late-life GAD and set the stage forfuture investigations of generalized self-efficacy expectancies and outcome expectancies (or optimism) as they relate to the prediction of affect and behavior in this group. 相似文献
154.
Cross-correlation and most other longitudinal analyses assume that the association between 2 variables is stationary. Thus, a sample of occasions of measurement is expected to be representative of the association between variables regardless of the time of onset or number of occasions in the sample. The authors propose a method to analyze the association between 2 variables when the assumption of stationarity may not be warranted. The method results in estimates of both the strength of peak association and the time lag when the peak association occurred for a range of starting values of elapsed time from the beginning of an experiment. 相似文献
155.
Deferred imitation of object-related actions and generalization of imitation to similar but not identical tasks was assessed
in three human-reared (enculturated) chimpanzees, ranging in age from 5 to 9 years. Each ape displayed high levels of deferred
imitation and only slightly lower levels of generalization of imitation. The youngest two chimpanzees were more apt to generalize
the model's actions when they had displayed portions of the target behaviors at baseline, consistent with the idea that learning
is more likely to occur when working within the "zone of proximal development." We argue that generalization of imitation
is the best evidence to date of imitative learning in chimpanzees.
Electronic Publication 相似文献
156.
Cross-sociocultural group measurement equivalency is an important issue that generally has not been studied in the coping literature. Measurement equivalency of the COPE (Carver, Scheier, & Weintraub, 1989) was assessed across two sociocultural groups, a sample of 100 Anglo middle-class divorced mothers and a sample of 122 low-income Mexican American/Mexican immigrant mothers. A series of restrictive confirmatory factor analyses revealed that seven of the COPE's subscales may be measuring the same underlying construct across populations. However, scores derived from the subscales may not represent the same magnitude of the construct in these two groups. This study makes an important first step in furthering the understanding of coping strategies in low-income Mexican American/Mexican immigrant mothers. This study also illustrates the importance of testing for measurement equivalency before conducting comparative research in disparate populations. 相似文献
157.
A survey of 71 graduates of the psychology residency program at The University of Texas Houston Medical School and the Texas Research Institute of Mental Science indicated that two-thirds of the respondents were involved in private practice, conducting primarily individual therapy, with assessment also playing a major role in their practice. Managed care had the effect of placing limits on the numbers of sessions available to patients, reducing income, and increasing paperwork associated with practice. Implications for training during residency are that individual therapy, using focused short-term approaches, and assessment should continue to be the primary clinical experiences for trainees, and that there should also be training in the business aspect of practice, including marketing. 相似文献
158.
The effect of sentence priming on picture naming was investigated across the lifespan, from age 3 to 87 years. Names that are normally acquired before 3 years of age were presented in auditory contexts that were semantically congruent, incongruent, or neutral in relation to each picture and its name. Sentential priming was present at all age levels. Facilitation (neutral vs. congruent) was significantly by 4 years of age and did not vary significantly with age. Interference (incongruent vs. neutral) was significant at all age levels, but changed nonmonotonically with age (largest in the youngest children, stable from young adulthood through age 70, with a small increase in the oldest participants). We conclude that picture naming is a useful tool for the investigation of sentential priming effects across the lifespan and that it can reveal potentially interesting developmental changes in the effects of sentential context on word retrieval. 相似文献
159.
Simkins-Bullock J 《Neuropsychology review》2000,10(1):41-74
While the intracarotid amobarbital procedure (IAP) was originally utilized to lateralize speech functions as an aid in the surgical treatment of epilepsy, additional uses for the IAP have emerged including: (1) the use of the IAP to predict post-surgical memory changes, including both global amnesia and smaller, yet significant, material-specific memory deficits; (2) the use of the IAP to provide confirmatory evidence of lateralization of seizure focus; and (3) the use of the IAP to predict post-surgical relief from seizures. While the literature on the IAP is extensive and growing, its utility is marred by the wide variability associated with the procedure itself from epilepsy center to center. This variability renders comparisons among IAP studies problematic and conclusions about IAP efficacy difficult. The variability associated with the amobarbital procedures, as well as the reliability and the validity of the IAP in its nonlanguage uses is reviewed here. A special emphasis is devoted to research conducted in the last decade. Also discussed is the future of the IAP including anticipated research directions. 相似文献
160.
Confidence and accuracy, while often considered to tap the same memory representation, are often found to be only weakly correlated
(e.g., Bothwell, Deffenbacher, & Brigham, 1987; Deffenbacher, 1980). There are at least two possible (nonexclusive) reasons
for this weak relation. First, it may be simply due to noise of one sort or another; that is, it may come about because of
both within- and between-subjects statistical variations that are partially uncorrelated for confidence measures on the one
hand and accuracy measures on the other. Second, confidence and accuracy may be uncorrelated because they are based, at least
in part, on different memory representations that are affected in different ways by different independent variables. We propose
a general theory that is designed to encompass both of these possibilities and, within the context of this theory, we evaluate
effects of four variables—degree of rehearsal, study duration, study luminance, and test luminance—in three face recognition
experiments. In conjunction with our theory, the results allow us to begin to identify the circumstances under which confidence
and accuracy are based on the same versus different sources of information in memory. The results demonstrate the conditions
under which subjects are quite poor at monitoring their memory performance, and are used to extend cue utilization theories
to the domain of face recognition. 相似文献