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101.
A preparation for the experimental analysis of cigarette smoking is described in detail. The preparation permits the intensive study of cigarette smoking in individual subjects under controlled laboratory conditions. A variety of behavioral and physiological measures used include rate and pattern of puffing, duration of each puff, time spent smoking cigarettes, expired air carbon monoxide levels, cigarette butt weights, and subjective rating scales of various aspects of smoking. The preparation is reliable and permits relatively unobtrusive monitoring of smoking performance. Cigarette smoking occurs in orderly patterns, within subjects; it varies as a function of number of cigarettes provided and hours of smoking deprivation. 相似文献
102.
College recruiters evaluated the qualifications and employability of either a male or a female applicant for a supervisory position. Half the recruiters in the experiment viewed a videotape of the candidate presenting himself or herself in a passive manner. The other half of the recruiters viewed a moderately aggressive interviewee. Contrary to the hypotheses, the moderately aggressive female was rated as favorably as the moderately aggressive male and the passive male was rated as negatively as the passive female. Although recruiters were as willing to hire a moderately aggressive male as they were the moderately aggressive female, they perceived the female's overall qualifications and her experience/training as superior to that of the male's. 相似文献
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In Experiment 1, rats were given a 1-pellet reward for 48 preshift trials. During a subsequent 20-trial postshift phase, one group was shifted to a 12-pellet reward on Trial 1, a second was shifted on Trial 11, and a third was given 1 more pellet each trial and then 12 pellets for the last 10 trials. The speeds of all three groups increased to a level above that of a control group given a 12-pellet food reward throughout training (positive contrast). In experiment 2, rats were shifted from 1 to 12 pellets either gradually or abruptly following either abbreviated training (9 trials) or extended training (20 trials). One group of control subjects received 12 pellets throughout training. The results revealed a positive contrast effect for gradually shifted subjects following extended training but not following abbreviated training. The abrupt shift procedure produced positive contrast following abbreviated training but only a marginal effect following extended training. These results indicate that, contingent upon the amount of preshift training, either gradual or abrupt reward increases may produce positive contrast. 相似文献
105.
Subjects were monaurally presented with consonant—vowel syllables to the right or left ear, with or without simultaneous noise to the other ear. The subject's task on each trial was to indicate whether or not the item presented was the target item /ba/. A right-ear advantage in reaction time was obtained: 14 msec for target items, 6 msec for nontarget items. The size of this effect was comparable in the presence vs. absence of competing noise. No consistent individual differences were found in the size of the right-ear advantage for this task, although such differences were obtained in a dichotic-perception pretest.It is argued that data of this type do not permit inferences about the use of particular ear/hemisphere neural pathways. 相似文献
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Nancy L. Segal PhD 《Suicide & life-threatening behavior》2009,39(6):569-575
Genetically informative samples can address hereditary and experiential influences on suicide‐related behaviors. The frequency of suicide‐related behaviors was compared in twins from two survivor groups: (1) those whose co‐twins' deaths were suicides (monozygotic [MZ]: n = 47; dizygotic [DZ]: n = 31), and (2) those whose co‐twins' deaths were nonsuicides (MZ: n = 347; DZ: n = 170). The frequency of suicide attempts among suicide survivors was significantly higher in MZ than DZ twins, while the frequency of suicide attempts among nonsuicide twin survivors did not differ between MZ and DZ twins. Twin concordance for suicide attempts more likely reflects a genetic predisposition than a behavioral reaction to the loss. 相似文献
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The disambiguation of a syntactically ambiguous sentence in favor of a less preferred parse can lead to slower reading at the disambiguation point. This phenomenon, referred to as a garden-path effect, has motivated models in which readers initially maintain only a subset of the possible parses of the sentence, and subsequently require time-consuming reanalysis to reconstruct a discarded parse. A more recent proposal argues that the garden-path effect can be reduced to surprisal arising in a fully parallel parser: words consistent with the initially dispreferred but ultimately correct parse are simply less predictable than those consistent with the incorrect parse. Since predictability has pervasive effects in reading far beyond garden-path sentences, this account, which dispenses with reanalysis mechanisms, is more parsimonious. Crucially, it predicts a linear effect of surprisal: the garden-path effect is expected to be proportional to the difference in word surprisal between the ultimately correct and ultimately incorrect interpretations. To test this prediction, we used recurrent neural network language models to estimate word-by-word surprisal for three temporarily ambiguous constructions. We then estimated the slowdown attributed to each bit of surprisal from human self-paced reading times, and used that quantity to predict syntactic disambiguation difficulty. Surprisal successfully predicted the existence of garden-path effects, but drastically underpredicted their magnitude, and failed to predict their relative severity across constructions. We conclude that a full explanation of syntactic disambiguation difficulty may require recovery mechanisms beyond predictability. 相似文献