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Real relational structures of scale type (1, 2) can be represented in the reals in such a way that the induced automorphism group is properly contained in the affine group and itself properly contains the group of translations. There are no real relational structures of scale type (m, m + 1), m ≥ 2.  相似文献   
85.
Rats were given backward pairings of a tone (CS) and shock (US) and were then tested for response to the CS in a lick suppression test. Animals given a cuing or reminder treatment prior to the test exhibited enhanced suppression in the presence of the tone relative to a variety of control conditions. The cue-induced suppression enhancement did not appear to result from sensitization or short-term motivational changes nor did it seem to depend on second-order conditioning of the test context. The effect appeared more robust as the number of backward conditioning trials preceding the cue increased. The results were discussed in terms of current explanations of backward conditioning effects.  相似文献   
86.
The purpose of these two experiments was to determine (a) whether young children can be responsive to caloric density cues in regulating their food intake, (b) whether such cues can be associatively conditioned to organoleptic cues in foods, and (c) to obtain evidence regarding which of the many cues available are involved as conditioned stimuli. In Experiment 1 participants were eighteen 3- to 5-year-old children, who were seen for a series of pairs of conditioning trials, followed by extinction test trials. Each trial consisted of a two-part snack: approximately 100 ml of a pudding preload (chocolate or vanilla; high or low caloric density) followed after a delay by ad-lib consumption of snack foods (cookies and crackers). In extinction trials, flavors previously paired with high- or low-caloric density preloads during conditioning were presented in isocaloric intermediate density preloads. Results indicated that 14 of 18 children showed unconditioned caloric compensation on the first pair of conditioning trials; 16 of 18 children showed compensation following the second pair of trials, and 12 of these 16 subjects continued to show this consumption pattern during extinction. Consumption was significantly greater following the low calorie paired flavor than following the high calorie paired flavor during extinction. Experiment 2 (N = 10) replicated these findings, and uncorrelating preload and snack food flavors indicated that flavor cues in the preloads can serve as conditioned stimuli. Children showed both initial responsiveness to caloric density and evidence for associative conditioning of food cues to the physiological consequences of eating. These results provide initial evidence for a mechanism allowing the child to learn to anticipate the caloric consequences of familiar foods and regulate food intake accordingly.  相似文献   
87.
In a conditioned inhibition paradigm (A+, B+, AX?_, pigeons received either of two keylight stimuli reliably followed by food (A+, B+). However, when one of these keylights was accompanied by another stimulus, food did not follow (AX?). For some groups, the putative inhibitor was a tone, whereas for others it was illumination of a red houselight. The birds pecked the A and B stimuli at a high rate. When X was red houselight, the birds pecked A at a much lower rate in the presence of X. When X was a tone, discrimination between A and AX was much poorer. Moreover, in a transfer test, red houselight inhibited responding to the other keylight, B, but tone did not. These results indicate that red houselight becomes a conditioned inhibitor more quickly than tone in appetitive situations, just as red houselight becomes a conditioned excitor more quickly in those situations. These results contradict the assertion that the latter outcome occurs because red houselight is a stronger appetitive excitor than tone at the start of the experiment (the “head start” hypothesis).  相似文献   
88.
The present experiments studied a three-event delayed sequence-discrimination (DSD) task: one arrangement (order) of two stimuli (red and yellow overhead lights) taken three in succession (e.g., red, yellow, red) was the positive sequence and the remaining seven arrangements were the negative sequences for responding and reward during the subsequent test stimulus. In Experiment 1, the final stimulus (recency) and the order of stimuli in the positive sequence controlled acquisition of discrimination. In Experiment 2, increasing the duration of memory intervals between stimuli reduced the discriminability of those negative sequences identical to the positive sequence after the delay. Three-event DSD performance in Experiments 1 and 2 was similar to two-event DSD performance in comparable published experiments. Models developed to explain pigeon performance in two-event DSD were extended to the three-event task. Results from both two- and three-event versions of the DSD task falsified a noncumulative model and several cumulative integration models (i.e., adding, averging, and some multiplying models), but corroborated one cumulative, multiplying model.  相似文献   
89.
Previous publications emanating from the Colorado Adoption Project have reported significant relationships between parental general cognitive ability (g) and infant Bayley MDI scores. The present study compared infant Bayley factor scores representing separable dimensions of infant cognition with parental general and specific cognitive abilities for 182 adoptive families and 164 nonadoptive families. Parent/offspring correlations between 12-month Bayley factors and parental cognitive abilities suggest only minimal relationships for both parental g and specific abilities. At 24 months, more parent/offspring resemblance was present; moreover, Bayley factors that were related to parental cognition tended to be related to parental g, not to specific abilities. The finding of significant parent/offspring relationships at 24 months between biological parents and their adopted-away infants, as well as between nonadoptive parents and their infants, suggests some genetic continuity from infancy to adulthood.  相似文献   
90.
In his theorizing about self-actualization, Maslow speculated that physical ability and physical self-confidence were two aspects of cooperative dominance which were associated positively with actualization. These aspects of dominance bear close resemblance to the Perceived Physical Ability (PPA) and the Physical Self-Presentation Confidence (PSPC) dimensions of the Physical Self-Efficacy (PSE) Inventory. Accordingly, the PPA and PSPC scores of undergraduate men and women were correlated with their scores on the Personal Orientation Inventory (POI), a popular measure of actualization, to test Maslow's hypotheses. The results showed that, contrary to Maslow's claims, PPA is not a positive correlate of self-actualization. However, strong support was found for Maslow's contention that high-PSPC individuals are more likely to be actualizing than low-PSPC people. Also, Maslow's hypothesis that actualizers are high in global sensation seeking (SS) was tested. The data indicated that only male actualizers were high in various aspects of SS, but female actualizers were not. Multiple regression analyses revealed further that both SS and PSPC are primary contributors to POI for men, but only PSPC contributes significantly to POI for women. Discussion focused on the reasons why research findings showing that increases in physical fitness lead to increases in self-esteem cannot be used to support the view that physical fitness and actualization are linked positively.  相似文献   
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