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261.
The process of olfactory sensation is probably a Gestalt consisting of motor, physical, and chemical components formed during the transport of the odor-bearing airstream past the olfactory epithelium. In studying a sensory process, it is often necessary to examine the components independently. Apart from its contribution to the olfactory Gestalt, in dynamic olfactometry airflow may distract from, compete with, or mask chemical sensation. Four nonsmoking male subjects were employed to obtain flow thresholds of nonodorous air at eight temperature/ humidity combinations. The stimulus-generating apparatus was housed in a temperature-regulated oven. All materials in contact with the airstream were thoroughly cleaned and were constructed of nonreactive materials to avoid olfactory cues. An evaluation of the quality of the output demonstrated purity. A Béésy technique was used to deliver stimuli via a nasal catheter to the subject. Thresholds were found to be nearly identical for the lowest humidity levels regardless of the temperature. In general, the closer the temperature/humidity was to physiological normal, the higher the threshold. Since the thresholds were so strongly functions of temperature and humidity, it is likely that transduction was by trigeminal thermoreceptive afferents. The utilization of subthreshold flows in olfactory research may reduce the trigeminal component in olfaction, thus permitting better assessment of the contribution of the olfactory nerve to olfactory sensation. 相似文献
262.
Subjects classified sets of multidimensional stimuli into two groups in any way they wished. The sets were composed of 6 or 12 stimuli: 2 or 4 instances of 3 different stimuli (e.g., 2 blue circles, 2 green circles, 2 red circles). There were striking individual differences in the preferred classification. Some subjects maximized the similarity between subgroups by matching the composition of the subgroups--one instance of each stimulus was placed in each group. The other subjects maximized the similarity among stimuli within each subgroup by placing similar stimuli in each group (the blues and greens in one group, the reds in the other). The nature of the stimuli as well as the relationships among the three stimuli had little effect on classification. In this case, cognitive styles specific to individuals but general across diverse dimensions and stimulus sets determined classification. 相似文献
263.
James R. Sawusch Howard C. Nusbaum Eileen C. Schwab 《Attention, perception & psychophysics》1980,27(5):421-434
Recent experiments have indicated that contrast effects can be obtained with vowels by anchoring a test series with one of the endpoint vowels. These contextual effects cannot be attributed to feature detector fatigue or to the induction of an overt response bias. In the present studies, anchored ABX discrimination functions and signal detection analyses of identification data (before and after anchoring) for an [i]-[I] vowel series were used to demonstrate that [i] and [I] anchoring produce contrast effects by affecting different perceptual mechanisms. The effects of [i] anchoring were to increase within-[i] category sensitivity, while [I] anchoring shifted criterion placements. When vowels were placed in CVC syllables to reduce available auditory memory, there was a significant decrease in the size of the [I]-anchor contrast effects. The magnitude of the [i]-anchor effect was unaffected by the reduction in vowel information available in auditory memory. These results suggest that [i] and [I] anchors affect mechanisms at different levels of processing. The [i] anchoring results may reflect normalization processes in speech perception that operate at an early level of perceptual processing, while the [I] anchoring results represent changes in response criterion mediated by auditory memory for vowel information. 相似文献
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265.
James P. Cunningham 《Memory & cognition》1980,8(6):593-605
The form of the memory representation for visual patterns consisting of a few line segments was investigated with three tasks. One task was the reproduction of remembered patterns using pencil and paper. The order in which the subparts of those patterns were reproduced was used to make suggestions about possible memory representations for the patterns. The second task involved rating the “goodness” of subparts of the patterns. These ratings were also interpreted as reflecting the underlying representations of the patterns. In the third task, the time required to recognize that a small pattern was part of a larger remembered pattern was used as further evidence about the memory representations of the patterns. The results from all three tasks are consistent with the theory that the memory representations are tree structures. Methods for deriving and comparing tree structures are discussed. 相似文献
266.
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268.
This study examines predictors of turnover of female factory workers in a multivariate framework. Findings indicate that organizational, job, and personal characteristics are equally important in explaining turnover. Variables significantly related to turnover were tenure, cycle time, peer leadership, communication flow, training time, family income, and satisfaction with pay. The AID technique was demonstrated as a means of identifying interaction effects. 相似文献
269.
James Jaccard Daniel Hand Lucille Ku Kathleen Richardson Rudolfo Abella 《Journal of applied social psychology》1981,11(3):181-191
Four factors (effectiveness, health risks, cost, and convenience) were orthogonally manipulated in a 3 × 2 × 2 × 2 factorial design to determine their relative importance in influencing attitudes toward and intentions to use male oral contraceptives. The experimental design also permitted a test of the assumption of additivity underlying expectancy-value models of attitude and the assumption of absence of context effects. Results were consistent with expectancy-value models of the relationship between beliefs and attitudes. In addition, it was found that health risks and effedtiveness, in that order, were the most important factors influencing receptivity to male oral contraceptives, with the effects of cost and convenience being mediated by these two factors. Sex differences in attitudes toward male oral contraceptives were also observed. 相似文献
270.
James Jaccard 《Journal of experimental social psychology》1981,17(3):286-307
The relationship between attitudes and behavior was considered. An attitudinal model of behavioral alternatives was presented and its applied and theoretical implications explicated. Three investigations were reported that tested the initial viability of the approach. Support for the model was observed in all three investigations. 相似文献