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91.
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   
92.
93.
The present research investigated the effects of experimentally induced positive and negative feedback about the self on the recipient's subsequent reactions to aid. In line with a consistency prediction, subjects given positive feedback who later received aid had lower mood ratings and less favorable self-evaluations than those who were given positive feedback but no subsequent help. Conversely, subjects given negative feedback who later received aid had higher mood ratings and more positive self-evaluations than those who were given negative feedback but no subsequent help. Subjects' evaluations of another individual were characterized by aid main effects, which indicate that an other who helped was evaluated more favorably than an other who did not help. The conceptual and applied implications of these results are discussed.  相似文献   
94.
Hyperactive and matched control boys at two age levels were compared on teacher ratings of peer interaction and three measures of social perspective-taking. The teachers' ratings of peer interaction discriminated between the hyperactive children and their controls. In addition, a significant interaction effect indicated that teachers rated the older hyperactive group as more deviant with peers than both their younger hyperactive counterparts and their age-matched controls. In a structured laboratory setting, the hyperactive children did not differ from control children on the three measures of social perspective-taking. The perspective-taking measures did, however, show differences across age groups. Implications for treatment are examined.The research reported in this paper is based on master's thesis submitted to the Graduate Faculty of Arts and Sciences of the University of Pittsburgh by the first author. The authors are indebted to Dr. C. Keith Conners for his assistance in recruiting hyperactive subjects and to Drs. Alex Siegel and Carl Barenboim for their critical evaluations regarding this investigation. Appreciation is expressed to the staff, teachers, parents, and students of the Forest Grove Elementary School for their cooperation.  相似文献   
95.
Sequential dependencies were examined as a function of learning, masking, and subject factors in a two-stage differential eyelid conditioning experiment. In Stage 1, all subjects were differentially conditioned to two Vanderplas and Garvin (1959) forms. In Stage 2, the conditional stimuli (CSs) were one of eight words, four reinforced (CS+) and four unreinforced (CS?), with taxonomic category (animalsvs. musical instruments) as the discriminandum, and different subjects were given semantic, physical, or no additional CS processing tasks. The results showed sizeable and highly significant sequential dependencies in the form of greater conditional response probabilities when CS + as opposed to CS? trials were recently experienced. These effects decreased overtrials, were greater in the groups given additional processing loads, and were in some cases greater in C-form responders than in V-form responders and greater in subjects who were unable to verbalize the differential contingencies. It was concluded that the magnitude of sequential dependencies was inversely related to the subject’s awareness of the differential contingencies and/or ability to use the contingency information to respond appropriately to the CS cues.  相似文献   
96.
97.
Rats received Pavlovian aversive (shock) conditioning in which white noise was established for independent groups as a CS+, CSo, or CS−. Then, in an easy (light-dark) T-maze discrimination, the CS was presented either immediately following choice (Locus 1) or at the food cup in the goal (Locus 3), contingent upon either a food-reinforced (right) or nonreinforced (wrong) response. When presented at Locus 3, the CS+ facilitated and the CS− retarded learning for CS/right subjects, with these effects being exactly reversed but somewhat less pronounced for CS/wrong subjects. However, when the CS was presented at Locus 1, the CS+ and CS− effects for both response contingencies were attenuated. These findings oppose an interpretation of the CS's function as a general cue or transformed signal for the presence or absence of the new appetitive reinforcer and argue instead for across-reinforcement blocking effects: By signaling in the presence of food reinforcement an outcome (safety or shock) which is consonant with or discrepant from the “good” outcome obtained, the CS− blocks (retards) and the CS+ counterblocks (enhances) the association of food reinforcement and the SD; conversely, in the presence of nonreinforcement (a “bad” outcome), the CS− counterblocks and the CS+ blocks inhibitory conditioning to the SΔ. As in Kamin's (1968) original research, such effects are attenuated when the CS is presented early in the compound, distal to the reinforcer.  相似文献   
98.
99.
In contrast to a recent finding (Macdonald, G. E., & De Toledo, L. Learning and Motivation, 1974, 5, 288–298.) the results of three experiments investigating various partial reinforcement (PRF) manipulations under conditions of thirst motivation demonstrated strong similarity to analogous manipulations involving food reward. Specifically, for animals receiving water reinforcement, PRF was shown to generate greater resistance to extinction than continuous reinforcement (Expt 1 & 3), the schedule of reinforcement was shown to interact with level of acquisition (Expt 1 and 2), and the magnitude of the partial reinforcement extinction effect was shown to be a function of reward magnitude (Expt 3). These results provide strong evidence that mechanisms which operate in partial reinforcement situations are highly similar, regardless of the type of appetitive reinforcement.  相似文献   
100.
The effects of stress on trait and state anxiety of emotionally disturbed, normal, and delinquent children were assessed using the State-Trait Anxiety Inventory for Children (STAIC). This scale measures both transitory feelings of apprehension and tension that vary over time as a function of situational stress (A-State) and individual differences in the disposition to experience such anxiety states (A-Trait). Results indicated that A-State increased as a function of stress, whereas A-Trait was relatively stable and impervious to the temporary effects of stress. Use of the STAIC with normal and deviant populations was supported.  相似文献   
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