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951.
The aim of these experiments was to determine whether impaired retention performance in aversively motivated tasks, induced by blockade of amygdala AMPA receptors, is due to influences on mechanisms underlying memory retrieval or to other influences on performance. Rats received either footshock escape training (1 or 10 trials), or no foot shock, in a two-compartment straight alley and bilateral intra-amygdala infusions of the AMPA receptor antagonist CNQX (0.5 μg) were subsequently administered prior to inhibitory avoidance retention testing 8 days later. The CNQX impaired, but did not block, inhibitory avoidance retention performance as indicated by the initial latencies to enter the shock compartment. The animals were then retained in the alley until they remained in the starting compartment for 100 consecutive s and entries into the shock compartment were recorded as errors. In both the controls and CNQX-treated groups, increases in amount of original training resulted in fewer errors, indicating memory for the escape training. Furthermore, regardless of the amount of original training (i.e., 0, 1, or 10 trials), CNQX-treated groups made more errors. Other experiments examined intra-amygdala CNQX effects on reactivity to footshock, locomotor activity, and anxiety. CNQX decreased reactivity to footshock, blocked shock-induced decreases in locomotor activity, and had an anxiolytic effect in an elevated plus maze comparable to that induced by midazolam (0.5 μg). These findings suggest that intra-amygdala infusions of CNQX prior to retention testing affect inhibitory avoidance retention performance following aversive training by altering locomotor activity, reducing sensitivity to footshock, and reducing anxiety. The implications of these findings for hypotheses concerning amygdala function in aversively motivated learning and memory is discussed.  相似文献   
952.
New York State's initial attempt at individualizing services occurred within the context of an experiment. We randomly assigned children 5–12 years old who were referred for out-of-home placement in treatment foster care to either treatment foster care, Family-Based Treatment (n=15), or to Family-Centered Intensive Case Management (FCICM) (n=27). FCICM used teams of case managers and parent advocates to provide in-home services. Flexible service dollars, respite care, and behavior management skills training were available to assist teams in individualizing care. Preliminary outcomes indicate that children in FCICM are doing as well or better than children assigned to FBT in their functioning and symptom reduction. Parents of children in FCICM have made gains, although not at a statistically significant level, in behavior management skills and family strengths that allow them to provide care for their children at home.  相似文献   
953.
We tested the notion that better foster care adjustment would be observed when the temperaments of mothers and fathers were matched with those of adolescent foster children. We hypothesized that families in which foster parents and foster children had high (easy) scores on subscales of the Revised Dimensions of Temperament Scale (DOTS-R) would also report higher family functioning and higher foster care adjustment than parents and children from families in which one or both family members had low (difficult) scores on these scales. The hypotheses were supported when the mothers and fathers family assessments were used but rejected when the observations of the case managers and adolescents were tested. Methodological and substantive explanations for the findings are discussed and recommendation for foster care practice and continuing research are provided.  相似文献   
954.
This paper makes the assumption that organ transplantation is, under some conditions at least, a proper use of communal medical resources. Proceeding from this assumption, the author: (1) sketches the history of the problem; (2) briefly examines the prevalent models of communal structure and offers an alternate version; (3) discusses notions of justice and obligation derived from these different models; (4) applies these to the practice of harvesting organs for transplantation; and then (5) offers a different process for harvesting organs from the newly dead. If community is viewed as united by a set of shred goals and common values among which the value of community itself is important, then certain reciprocal obligations among members obtain. I suggest that routine salvage of organs from the newly dead be instituted but that it be routine salvage “with a twist”: rather early in life all members of the community are given the opportunity to refuse but their refusal carries the reciprocal condition that they cannot later become the recipients of that which they refuse to others.  相似文献   
955.
An aftereffect of perceived texture density contingent on the color of a surrounding region is reported. In a series of experiments, participants were adapted, with fixation, to stimuli in which the relative density of two achromatic texture regions was perfectly correlated with the color presented in a surrounding region. Following adaptation, the perceived relative density of the two regions was contingent on the color of the surrounding region or of the texture elements themselves. For example, if high density on the left was correlated with a blue surround during adaptation (and high density on the right with a yellow surround), then in order for the left and right textures to appear equal in the assessment phase, denser texture was required on the left in the presence of a blue surround (and denser texture on the right in the context of a yellow surround). Contingent aftereffects were found (1) with black-and-white scatter-dot textures, (2) with luminance-balanced textures, and (3) when the texture elements, rather than the surrounds, were colored during assessment. Effect size was decreased when the elements themselves were colored, but also when spatial subportions of the surround were used for the presentation of color. The effect may be mediated by retinal color spreading (Pöppel, 1986) and appears consistent with a local associative account of contingent aftereffects, such as Barlow’s (1990) model of modifiable inhibition.  相似文献   
956.
Fetal brain tissue from the occipital or the frontal cortex was implanted into the damaged occipital cortex of adult rats. The animals receiving grafts of embryonic frontal cortex showed partial restoration of brightness discrimination while recipients given homologous implants of occipital cortex were as impaired as those animals with lesions alone. Neither frontal nor occipital grafts aided in the performance of a pattern discrimination problem; both groups of brain-damaged animals were unable to learn the task. Nonetheless, both groups of animals had viable and enlarged grafts with similar neuronal and glial profiles.  相似文献   
957.
Cocaine use in the United States has currently reached epidemic proportions. This has resulted in syndromes of intoxication, overdose, and withdrawal, meeting all DMS-III criteria for a substance that can cause dependence as well as abuse syndromes. This paper reviews the current epidemiology of cocaine, its history and pharmacology with major focus on clinical syndromes. This is followed by a review of the current knowledge of the relationship between cocaine and violence and the forensic-psychiatric issues surrounding cocaine.  相似文献   
958.
959.
The present study attempted to identify behavioral skills associated with global perceptions of communication competence and to determine if the relationship between competence and skills varies as a function of perceptual locus. Fifteen dyadic conversations were videotaped. Each interactant rated self and partner and was rated by four observers who viewed each tape. Results indicated that subjects' perceptions of their partners' skills accounted for 87% of the variance in subjects' ratings of partners' competence and 80% of the variance in subjects'self-perceived confirmation. Observers' ratings of subjects' skills predicted 83% of the variance in observers' ratings of subjects' competence. Observers'ratings of subjects'skills were unrelated to subjects' self-rated competence.  相似文献   
960.
The truncated nuclear family is defined: it is the garden-variety family pathology found. The critical role of polarized continuity and discontinuity values in producing the truncated nuclear family is discussed. There is a brief review of factors in American society which, over the decades since the Second World War, have evolved the nuclear family as a dominant family unit, and of how those and other factors in society have produced the large numbers of truncated nuclear families seen in clinics, particularly in the past decade. Family therapy is the treatment of choice for the truncated nuclear family, provided there is a readiness of the family to undertake the stress of therapy.Dr. Zuk is family therapy consultant to agencies in New Orleans and elsewhere, and clinical professor (psychology) in the Department of Psychiatry and Neurology at Tulane University Medical School.This paper is a chapter in the forthcoming 2nd edition ofProcess and Practice in Family Therapy, to be published by Human Sciences Press of New York City in 1985.  相似文献   
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