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851.
Lawrence J. Folinsbee Jeffrey A. Gliner Steven M. Horvath 《Attention, perception & psychophysics》1982,32(5):449-453
Man is capable of reproducing an inspired lung volume (IV) with relative precision (±3 %–8 %). To investigate the importance of cues which may be used to determine IV, we performed two experiments. In each, the subject inspired a “standard” breath (from resting end~xpired lung volume) corresponding to 25%, 50%, or 75% of inspiratory capacity (IC) and then expired nearly completely. From this expired volume, the subject either tried to reproduce the tidal volume (i.e., volume of air inspired) of the first breath (volume reproduction) or to reproduce the previous end-inspired lung volume (position reproduction). The constant error indicated that subjects overestimated tidal volume by about 200 ml. Despite this overestimation, the variability of reproduction was less for volume reproduction than for position reproduction when IV was small. The JND for volume reproduction increased linearly with increasing IV, whereas the JND for position reproduction was similar at all IVs so that the Weber ratio decreased. These observations suggest that, in the perception of inspired volume, the sensation of end-inspired position is important when the inspired volume is large, but that subjects apparently rely on some other cue to reproduce small lung volumes accurately. 相似文献
852.
This article describes a group weight control project with severely obese adolescent girls in a medical setting. Behavior modification and nutritional principles were utilized with peer group interaction. Significant others were included through separate group meetings. This approach produced small amounts of net weight loss for the girls. The drop-outs continued to have a net gain. As a treatment method, this program was more effective for these girls than previous individual clinic contacts had been. When losing weight, the girls tended to use behavior modification techniques more often, and their diets became more adequate nutritionally. Development of group cohesion was tenuous and temporary. Girls who were functioning more independently appeared to do better in weight loss. Disinterested significant others were preferable to nonsupportive ones. A predictive factor was identified, the girls' perception of control. This was measured by the I-E test. Those with a more internalized perception of control were more likely to continue with the program and more likely to lose weight. Because the patient group was small, findings are tentative. However, this program helped to define particular areas that deserve further exploration. 相似文献
853.
Eighteen long stay male patients (diagnosis chronic schizophrenia) were involved in a six month token economy prior to random assignment to one of three experimental groups to investigate the importance of social reinforcement and other token-related variables in maintaining improvements brought about by the token system. Assessment included standardised psychiatric rating scales, nurse rating scales, and behavioural measures. Analysis of variance suggests the full token economy system produced significant improvements, but that the social factors involved in token exchanges were not demonstrably important sources of reinforcement. and that none of the variables studies at the experimental phase were critical factors. Once patients returned to a complete token system, results indicate that this may have more value in the promotion of work activities rather than social responding. It is argued that the token system provides a necessary clear structure within which nurses can encourage continuous improvements with long stay patients. 相似文献
854.
855.
C Grove F D O'Sullivan M Rodda 《British journal of psychology (London, England : 1953)》1979,70(4):531-540
One of the most important psychological effects of early severe or profound deafness is an impairment in natural language-processing ability, with a consequent reduction in communicative skill secondary to the sensory deficit. Prelingual damage blocks the development of certain sequential/syntactical skills necessary for the acquisition of normal linguistic competence. Educators of the deaf in the UK have typically attempted to improve linguistic ability using amplification and intensive training in lip-reading, but evidence from several psychological studies suggests that communication systems based upon manual signing are more productive of both linguistic and basic cognitive skills. This paper reports an experimental study of the communicative characteristics of both oral and total communication systems as a function of language structure. For almost all types of structure investigated, the total system was found to be the more effective method of communication. 相似文献
856.
857.
Richard F. Reichner 《Journal of applied social psychology》1979,9(1):13-26
This study examines the experience of being ignored when social interaction is chronically at high or low levels. Subjects in these studies resided in either traditional corridor dormitories or in suite-type apartments. Previous research has shown that the corridor arrangement leads to an excess of unwanted contacts with other residents. Hence, corridor residents should desire less interaction with strangers than suite residents. It was hypothesized that corridor residents would be less adversely affected if they were ignored during a group discussion. The results of two experiments reported here support this hypothesis. They also demonstrate the generally negative effects of being ignored. Results are discussed in terms of Altman's (1975) model of contact regulation. 相似文献
858.
R M Zacharko T B Wishart F M Loew 《Journal of comparative psychology (Washington, D.C. : 1983)》1979,93(1):140-150
The anorexic consequence of thiamin deprivation was investigated in ventromedial hypothalamic (VMH) hyperphagic rats under either high-fat or low-fat thiamin-free diet conditions. The low-fat diet maintained feeding significantly longer in thiamin-deprived VMH rats than in intact rats, whereas the hig-fat diet sustained feeding in thiamin-deficient intact rats and accelerated anorexia onset in vitamin B1 deprived VMH rats. This effect was noted under both ad lib and pair-feeding conditions. Thiamin-deprived VMH rats subjected to weight control developed anorexia sooner than intact subjects regardless of the diet employed. The VMH rats fed a high-fat diet failed to resume feeding after thiamin readministration, which was interpreted as a permanent aversion to this diet. The relation between dietary intake and conditioned taste aversion is discussed with reference to the VMH and intact rat. 相似文献
859.
J R Stellar F H Brooks L E Mills 《Journal of comparative psychology (Washington, D.C. : 1983)》1979,93(3):446-466
In a paradigm in which rats would both initiate and terminate hypothalamic stimulation, "purely" rewarding lateral hypothalamic and "purely" aversive medial hypothalamic electrodes were identified. Subjects were then given a series of tests designed to assess the effects of brain stimulation on approach and withdrawal behaviors. Lateral hypothalamic stimulation facilitated approach behavior and suppressed withdrawal behaviors, whereas medial hypothalamic stimulation produced largely the opposite effects. No serious motor deficits due to stimulation were detected with either type of electrode. In a second experiment, the approach-withdrawal effects of bilateral lateral hypothalamic lesions were tested and found to suppress approach behaviors and facilitate withdrawal behaviors. Other neurological examinations revealed motor deficits, but these deficits do not account for the specific pattern of results observed on the approach-withdrawal tests. These approach-withdrawal phenomena are interpreted in terms of altering a natural balance between approach and withdrawl behavior facilitating systems in the lateral and medial hypothalamus, respectively. 相似文献
860.
Michael F. Cataldo Cindee A. Bessman Lynn H. Parker Joyce E. Reid Pearson Mark C. Rogers 《Journal of applied behavior analysis》1979,12(1):83-97
Two studies were conducted to analyze behaviors of staff and patients on a Pediatric Intensive Care Unit (PICU). In the first study, behavioral observation procedures were employed to assess patient state, physical position, affect, verbal behaviors, visual attention and activity engagement, and staff verbal behavior. On the average, one-third of the patients were judged to be conscious and alert but markedly nonengaged with their environment. In the second study, a member of the hospital staff provided alert patients with individual activities to determine whether a simple environmental manipulation could positively affect behavior of children in intensive care. Employing a reversal design, the activity intervention was found to increase attention and engagement and positive affect, and to decrease inappropriate behavior. Both studies demonstrate that behavioral assessment procedures can provide an empirical basis for designing PICU routines affecting children's psychosocial status, and, thus, complement current procedures designed to provide quality medical care. 相似文献