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231.
The functional development of cardiac and adrenal medullary responses to reflex activation of the sympathetic nervous system was studied in preweanling spontaneously hypertensive (SHR) and Wistar-Kyoto (WKY) normotensive rats. Pups of the two strains received injections of insulin or saline at 2, 4, 8, 12, or 16 days of age and were sacrificed 3 h later. Insulin administration produces a significant decrease in circulating levels of glucose which in turn results in a centrally mediated increase in sympathetic outflow. The induction of ornithine decarboxylase (ODC) in heart and the depletion of epinephrine from the adrenal medulla served as tissue markers of functional sympathetic neurotransmission. WKY and SHR pups had comparable levels of ODC activity in heart under basal conditions. In contrast, levels of catecholamines in the adrenals were greater in SHR pups at 2 and 4 days of age. Following insulin administration, SHR pups exhibited a greater induction of cardiac ODC activity at 2, 4, and 8 days of age compared to age-matched WKY controls. However, there were no differences between SHR and WKY pups in the magnitude of the adrenal medullary response to insulin-induced hypoglycemia. These alterations in sympathetic-target tissue development during the first postnatal week of life may contribute in part to the higher arterial pressures maintained by SHRs throughout the lifespan. 相似文献
232.
Perceptual organization of acoustic stimuli by budgerigars (Melopsittacus undulatus): II. Vocal signals 总被引:1,自引:0,他引:1
R J Dooling T J Park S D Brown K Okanoya S D Soli 《Journal of comparative psychology (Washington, D.C. : 1983)》1987,101(4):367-381
Operant conditioning and multidimensional scaling procedures were used to study auditory perception of complex sounds in the budgerigar. In a same-different discrimination task, budgerigars learned to discriminate among natural vocal signals. Multidimensional scaling procedures were used to arrange these complex acoustic stimuli in a two-dimensional space reflecting perceptual organization. Results show that budgerigars group vocal stimuli according to functional and acoustical categories. Studies with only contact calls show that birds also make within-category discriminations. The acoustic cues in contact calls most salient to budgerigars appear to be quite complex. There is a suggestion that the sex of the signaler may also be encoded in these calls. The results from budgerigars were compared with the results from humans tested on some of the same sets of complex sounds. 相似文献
233.
This study is an extension of previous observational work on the social ecology of dependence and independence in the institutionalized elderly. Observations of everyday, naturally occurring interactions between elderly residents of two different long-term institutions and their social partners were extended such that, aside from the identification of type of behavior, the dyadic form and continuity of each behavior was specified. The following were among the major results: (a) Previously found interaction patterns between elderly residents and their social partners, replicated in both a nursing home and a home for the chronically ill, supported the notion of discrepant social ecologies for dependent versus independent behaviors of residents: (b) specification of each behavioral act as to its dyadic form underscored the fact that the interactions were controlled largely by social partners and not by the elderly residents; (c) coding continuity or discontinuity of behavior suggested that independent behaviors were maintained by chaining; and (d) elderly residents in the home for the chronically ill evinced, as expected, more dependence-related behaviors. 相似文献
234.
William T. Riley P. Alex Mabe James M. Schear 《Journal of psychopathology and behavioral assessment》1987,9(1):67-74
Seventy-five patients admitted to the psychiatric unit of a general hospital were administered a brief neuropsychological screening battery. Discharge diagnoses obtained from the medical records revealed that 20% had brainbased pathology. A discriminant function analysis resulted in a five-variable model (Symbol-Digit Modalities Test, educational level, Psychiatric-Organic subscale of the MMPI, and Shipley Vocabulary and Abstraction scores) which correctly classified 84% of the subjects, with 87% correct identification of the brain-damaged group. A jackknife cross-validation procedure resulted in comparable hit rates. 相似文献
235.
236.
Michael T. Nietzel Ronald C. Dillehay Melissa J. Himelein 《Behavioral sciences & the law》1987,5(4):467-477
With a sample of 18 capital cases tried in Kentucky, South Carolina, and California, we attempted to replicate an earlier study which showed that significantly more defense challenges for cause were granted under conditions of sequestered, individual voir dire than when voir dire was conducted under less enhanced conditions. In the current sample, sequestered, individual voir dire again resulted in more defense removals for cause than obtained with less extensive voir dire. We present data on the defense removals for cause partitioned into five categories according to the reason for the challenge and analyze the effects of jury selection consultants on the various indices of voir dire as well as final sentence. 相似文献
237.
238.
Two studies are reported on a new Anger Control Inventory based on a cognitive-behavioral person-situation interaction model. In Study 1, the inventory responses of 118 clinical subjects and 190 normal subjects were correlated with an anger problem criterion based on observable signs. Factor analyses were conducted to clarify the construct base of the inventory. In Study 2, comparisons were made between the inventory responses of 100 spouse batterers and 96 normal subjects. Significant differences between the pretreatment and posttreatment scores of 65 batterers given treatment in anger control were obtained on the inventory scales, which were found to be correlated with the problem criterion and discriminating between the clinical and normal groups. The construct validity and clinical utility of the Anger Control Inventory are discussed. 相似文献
239.
This study explored the relationship among love deprivation, Performance greater than Verbal discrepancy, and violent crime in a sample of juvenile probationers. Love deprivation and P greater than V discrepancy was significantly related to violent delinquency after adjusting for the effects of both race and social class, two variables often closely associated with violent delinquency. Also, love deprivation was strongly related to P greater than V discrepancy. We speculated that high performance IQ scores relative to verbal scores are a function of a lack of disruption in the short-term memory mechanisms of high P greater than V subjects, that this nondisruption is a function of hyporeactive autonomic nervous systems, and that this hyporeactivity could itself be a function of early love deprivation. 相似文献
240.
W V Dube W J McIlvane H A Mackay L T Stoddard 《Journal of the experimental analysis of behavior》1987,47(2):159-175
In an arbitrary matching-to-sample procedure, two mentally retarded subjects learned conditional discriminations with two sets of stimuli. Each set included a spoken name (N1 or N2), an object (O1 or O2), and a printed symbol (S1 or S2). One subject selected conditionally (a) O1 upon N1, and O2 upon N2, and (b) S1 upon O1, and S2 upon O2. The other subject selected conditionally (a) S1 upon N1, and S2 upon N2, and (b) O1 upon S1, and O2 upon S2. For both subjects, selections of O1 and S1 produced one type of food, F1; selections of O2 and S2 produced a different type of food, F2. Both subjects also learned identity-matching performances, selecting O1, O2, S1, S2, F1, and F2 conditionally upon those stimuli as samples; F1 followed selections of O1, S1, and F1; F2 followed selections of O2, S2, and F2. Matching performances consistent with stimulus class formation involving the names, objects, symbols, and foods were demonstrated on probe trials, even though these performances had not been taught explicitly. Next, new objects, X1 and X2, were presented on identity-matching trials, producing F1 and F2, respectively. Without further training, X1 was selected conditionally upon N1, S1, and O1, and X2 was selected upon N2, S2, and O2. When the contingencies were changed so that selections of X1 and X2 were now followed by F2 and F1, respectively, X2 was selected conditionally upon N1, S1, and O1, and X1 was selected upon N2, S2, and O2. Class membership of X1 and X2 had apparently changed. This study provides evidence that reinforcers may become members of stimulus classes, and that new stimuli may become class members through relations with reinforcers. 相似文献