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281.
Five pigeons were trained on concurrent variable-interval schedules. A series of conditions in which the ratio of reinforcement rates on two keys was progressively increased and then decreased was arranged twice. The birds were then exposed to an irregular sequence of conditions. Each condition in which reinforcement was available on both keys lasted six sessions. Performance in the first, third, and sixth sessions after a condition change was analyzed. Following a condition change, preference was biased toward the preference in the last condition, but this effect largely disappeared before the sixth session of training. The birds' preferences also appeared less sensitive to reinforcement rates in early sessions after a transition. Preference in a session was a function of both the reinforcements in that session and the reinforcements obtained in as many as four or five previous sessions. The effects of reinforcements in previous sessions could be summarized by the performance in the immediately preceding session, giving a relatively simple relation between present performance and a combination of present reinforcement and prior session performance. While such hysteresis could cause undermatching when only a small number of sessions are arranged in a condition, undermatching in a stable-state performance probably arises elsewhere. 相似文献
282.
Because carbon monoxide (CO) is an easily understood danger of cigarette smoking, new breath CO analyzers may be useful in cessation programs. Self-reported cigarette consumption and breath CO correlated .70 using a 90-sec. CO-determination method. Smokers averaging 17 daily cigarettes had average breath CO of 24 parts per million (ppm), falling to 7.71 ppm for smokers claiming at least 24-hr. abstinence. Corresponding carboxyhemoglobin (COHb) estimates were 4.34% (slightly above World Health Organization 4% safety limit) and 1.39%. Smoking clinics can use CO-monitoring devices for feedback or surveillance, although feedback would provide the most benefits for participants. 相似文献
283.
This study investigated the relationship between life stress and measures of anxiety, depression, and hostility as a function of subjects' arousal-seeking status. Results indicated significant relationships between negative life change and measures of both anxiety and hostility. These relationships, however, held only for subjects who were low on the arousal-seeking dimension. The results suggest that arousal-seeking status may serve as a moderator variable in determining the relationship between life stress and other variables. 相似文献
284.
Three types of oculomotor programming disturbances are described in patients with the dementia syndrome. This report describes two of these abnormalities, poorly regulated gaze patterns and a programming type of gaze perseveration. All patients showed poorly regulated gaze patterns in contrast to the normal controls, whereas on the whole only the moderately affected patients showed the programming type of gaze perseveration. The third type of oculomotor programming disturbance is efferent perseveration of gaze (a hypokinetic, "staring" type of gaze pattern) and can be seen with severe dementia. The possible significance of these findings is discussed. 相似文献
285.
Richard I. Lanyon Barbara P. Lanyon Robert J. Goldsworthy 《Journal of Fluency Disorders》1979,4(2):131-139
The MMPI and subscales of the Stuttering Severity scale were utilized to predict motivation and success in the behavioral treatment of 32 stutterers. Subjects spent a mean of 10 individual sessions in criterion-oriented learning of fluent speech based on speech-muscle relaxation aided by EMG visual biofeedback. Judged motivation and judged success were strongly related to each other and significantly related to MMPI K and Es scores and negatively to F and Sc. Actual success was negatively related to Sc and Pd, completely unrelated to Es, and (if anything) negatively related to K. Results are consistent with previous studies, and show that global judgements of progress were only minimally related to a measure of actual progress. 相似文献
286.
Orthography and familiarity effects in word processing 总被引:1,自引:0,他引:1
T H Carr M I Posner A Pollatsek C R Snyder 《Journal of experimental psychology. General》1979,108(4):389-414
Both orthographic regularity and visual familiarity have been implicated as contributors to the efficiency of processing visually presented words. Our studies sought to determine which of the internal codes representing words in the nervous system are facilitated by these two variables. To do this, sets of letter strings in which orthography and familiarity were factorially combined were used as the basis for physical, phonetic, semantic, and lexical judgments. The data indicated consistent effects of orthography on the activation of all codes. These effects were seen in same-different matching and in judgments of stimulus orientation, which are based on visual codes; in judgments of pronounceability based on phonetic codes; in judgments of meaningfulness based on semantic codes; and in lexical decisions, which are based on phonetic and semantic codes together. Familiarity, on the other hand, had a clear influence on the activation of semantic codes and to a lesser extent affected phonetic codes. Despite previous positive results found in matching letter strings, however, no influence of familiarity occurred in judgments based on visual codes once evidence for criterion shifting was eliminated. Our negative results included direct tests of facilitation in matching acronyms (e.g., FBI) and in matching both regular and irregular strings familiarized by specific training. It now appears that earlier findings of visual familiarity effects may be attributed to response biases resulting from the activation of higher level codes sensitive to familiarity, and to the use of small sets of training stimuli that allowed subjects to induce orthographic-like rules. The results obtained so far with our methods seem to reconcile an inconsistent literature by showing that speeded decisions based on visual codes are most strongly influenced by rule-governed processing mechanisms sensitive to orthographic structure, whereas decisions based on phonetic and semantic codes are affected about equally by rule-governed mechanisms and by stimulus-specific mechanisms sensitive to familiarity. This conclusion may lead to changes in notions of how effective various kinds of visual training are likely to be at different stages in the acquisition of reading skill. 相似文献
287.
E. I. Popova Eugenia Ivanovna Popova 《Integrative psychological & behavioral science》1979,14(1):61-63
Dogs were used to condition two instrumental reactions—bending of the left or of the right forepaw respectively. In the experimental situation a dish containing food was presented to the dog at a distance but could be drawn close and retained by lifting the forepaw to which (left or right) a lever had been attached. If both paws were simultaneously attached to levers, the dog had to choose between two reactions. Preliminary trials showed a right paw preference in spite of the equal effectiveness (food reinforcement) of the left paw. The aim of this experiment was to alter this right paw preference by a paradigm of differential practice with left paw dominance. The plan was to have ten training sessions followed by one test with choice. According to the probabilities, Pleft = 0.8, Pright = 0.2, a random table was used to determine the order of the right-left paw attachments to the levers during training. In all, 1,000 training sessions and 100 tests with choice were carried out in each of three dogs. According to the training program, in every 100 training sessions the left paw had to perform the reaction a total of 80 times and 20 times by the right paw. An absolute alteration in paw preference occurred Plelt = 1.0) even though both forepaws were equally effective in obtaining food reinforcement on the test trials. The present results indicate that not only the Law of Effect but Exercise is also important in instrumental conditioning. 相似文献
288.
289.
290.
Goldiamond I 《Journal of applied behavior analysis》1977,10(3):527-529