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811.
The use of magnitude estimation as well as axiomatic measurement theory has led to the suggestion that loudness adds across critical bands. In the present paper, we challenge this postulate by applying a more sensitive methodology, based on Falmagne’s (1976) random conjoint measurement procedure. A necessary condition for additivity of loudness was investigated in tone complexes consisting of 2-kHz and 5-kHz (resp. 3-kHz) components; the results showed systematic deviations from additivity. We argue that these deviations are due to asymmetric masking of the higher component by the lower one, and we propose a tentative quantitative model to account for the data. Such a model is in line with results from tone-on-tone masking, which show masking to be effective over a range of several critical bands. 相似文献
812.
The perception of continuously repeating auditory patterns by European starlings was explored in seven experiments. In Experiment 1, 4 starlings learned to discriminate between two continuously repeating, eight-element, auditory patterns. Each eight-element pattern was constructed from different temporal organizations of two elements differing in timbre. In Experiments 2–7, the repeating patterns were transformed in ways designed to identify the starlings’ perceptual organization of the patterns. In Experiment 2, the starlings identified patterns beginning with novel starting points. In Experiment 3, discrimination performance was adversely affected by reorganizing the elements in the patterns. In Experiments 4 and 5, the pattern elements were altered. In Experiment 4, the patterns were constructed from two novel elements. In Experiment 5, the temporal location of the two pattern elements was reversed. The transformations of the patterns in Experiments 4 and 5 affected discrimination performance for some, but not all, of the starlings. In Experiments 6 and 7, replacing either of the two elements with silent intervals had no effect on discrimination performance. The results of these experiments identify basic grouping principles that starlings use when they perceive auditory patterns. 相似文献
813.
David Foulkes Barbara Meier Inge Strauch Nancy H. Kerr Laura Bradley Michael Hollifield 《International journal of psychology》1993,28(6):871-891
Sixteen German-English bilinguals were studied in a sleep laboratory for four nonconsecutive nights each. Half were native English speakers living in Zürich, and half native German speakers living in Atlanta. Presleep thought samples were solicited each evening and REM dream reports each night; subjects judged the waking appropriateness of their imagined speech and language phenomena, and also identified waking sources of their dream imagery, the following mornings. Incidences of dreaming and of speech therein generally were similar to those of monolinguals. Whether sessions were conducted in German (two nights) or English (two nights) did directly influence language selection in subjects' dreams. Judged appropriateness of language selection to imagined events was very high for thought samples, and high for REM dreams. Sources for thought samples were generally consonant with the language dominant at study site; for REM dreams this relationship was considerably weaker. Judged waking appropriateness to imagined situations was more strongly related to language selection than was the language reference of the supposed sources of those situations. 相似文献
814.
815.
816.
817.
This study explored one mechanism through which acute disaster stress (injury, life threat, property damage, loss) may produce lasting psychological distress (depression, anxiety, somatization, hostility). More specifically, the study examined the mediating roles of seven domains of chronic stress (marital, parental, filial, financial, occupational, ecological, physical) within a sample of 930 disaster victims and controls. The results provided strong support for the hypothesis that chronic stress mediates the long-term effects of acute disaster stress on psychological distress. The main effects of loss, though limited in strength, were completely explained by victims’ higher financial, marital, filial, and physical stress. The effects of injury, though quite strong, were largely mediated by these same domains of chronic stress. Likewise, the effects of life threat were largely mediated by all these domains plus ecological stress. A mediational model was not appropriate for understanding the consequences of property damage because it did not exhibit a main effect on psychological distress. 相似文献
818.
Christopher R. Agnew Vaida D. Thompson Valerie A. Smith Richard H. Gramzow David P. Currey 《Journal of applied social psychology》1993,23(24):2013-2042
A proximal-distal theoretical framework was developed to examine the multivariate roots of homophobia. Using data from a sample of 288 undergraduates who had participated in a computer-assisted panel study over a three-year period, the effects on homophobia of distal and proximal family factors (e. g., parental education and family environment), distal and proximal individual factors (e. g., personality constructs and current beliefs), and proximal individual-situational factors (e. g., acquaintance with homosexuals) were tested in regression analyses. Both analyses employing sets of variables varying in proximity to the homophobic attitude and hierarchical regression employing variables contributing significantly in each set supported the proposed framework. All sets predicted significantly when regressed separately on homophobia; the sets containing the distal factors contributed most weakly, and the sets containing the proximal factors contributed most strongly. In hierarchical regression analysis, this pattern maintained such that the incremental increase in r2 decreased with the addition of each more distal set, with the most distal factors failing to contribute significantly to the prediction. The importance of study findings for attitude change efforts is discussed. 相似文献
819.
J. Stephen Newton William R. Ard Robert H. Horner 《Journal of applied behavior analysis》1993,26(2):239-245
We examined the accuracy of 24 staff members' predictions of activities preferred by 14 individuals with severe disabilities. For each of 144 activities, staff members assigned a client preference rating of “likes a lot,” “likes,” or “dislikes.” Two activities from each category were randomly selected for each individual with disabilities. Pairs of selected activities were presented to the individuals, who were prompted to choose an activity. Staff members' activity preference ratings correctly predicted the choices made by the individuals with disabilities for 78% of the trials. The more divergent the preference ratings of the paired activities, the more likely staff members were to predict correctly the activity selected by a participant. 相似文献
820.
Effects of differences between stimuli, responses, and reinforcer rates on conditional discrimination performance 总被引:5,自引:5,他引:0 下载免费PDF全文
In a discrete-trial conditional discrimination procedure, 4 pigeons obtained food reinforcers by pecking a key with a short latency on trials signaled by one stimulus and by pecking the same key with a long latency on trials signaled by a second stimulus. The physical difference between the two stimuli and the temporal separation between the latency values required for reinforcement were varied factorially over four sets of conditions, and the ratio of reinforcer rates for short and long latencies was varied within each set of conditions. Stimulus discrimination varied directly with both stimulus and response differences and was unaffected by the reinforcer ratio. Sensitivity to reinforcement, estimated by generalized-matching-law fits to the data within each set of conditions, varied directly with the response difference but inversely with the stimulus difference arranged between sets of conditions. Because variations in stimulus differences, response differences, and reinforcer differences did not have equivalent effects, these findings question the functional equivalence of the three terms of the discriminated operant: antecedent stimuli, behavior, and consequences. 相似文献