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241.
Previous research has shown that perceived odor strength does not vary with flow rate of an odorant vapor entering the naris when that variation is produced by subject-controlled changes in sniff pressure, but that it does vary with flow rate when the variation is produced by experimenter-controlled changes in the resistance of the olfactometric system. We have suggested an odor-constancy model in which invariance of perceived odor strength is linked to perceived effort of sniffing, and have hypothesized that changed resistance will have its effect because there is no corresponding change in perceived effort when sniff pressure is held constant. In two studies, subjects made magnitude estimations of the perceived effort of sniffing; sniff pressure was controlled by having the subject match his sniff, displayed on a storage oscilloscope face, to a pattern specifying its required shape, duration, and level. In Experiment 1, resistance was fixed while sniff pressure varied; perceived effort grew as the .8 power of the required sniff pressure. In Experiment 2, sniff pressure and resistance were varied in a factorial design; perceived effort grew as the .8 power of pressure at fixed resistance, but remained unchanged when resistance varied at fixed pressure. This outcome provides indirect support for the odor-constancy model, since it shows that perceived effort covaries with flow rate under the condition in which constancy is found but does not change under the condition in which constancy fails.  相似文献   
242.
Proctor (1981) presented a theoretical framework that distinguishes factors contributing to disparities in time to classify physical-same, name-same, and different letter pairs as a function of three variables: method of presentation (simultaneous vs. successive), case relationship (samecase vs. opposite-case pairs), and blocking (blocked vs. mixed presentation of same-case and opposite-case pairs). He also argued that these variables were critical in multIletter matches, and performed a between-study comparison of existing data to support his contention. Because comparison across studies is always a tenuous process and because the absence of several relevant conditions precluded a complete analysis of predictions, a within-experiment manipulation of the three relevant variables was desirable. The present study reports such an experiment. In general, the factorial manipulation of variables supported predictions of Proctor’s framework and indicated that many phenomena of multiletter matching, including the widely studied fast-“same” phenomenon, are attributable primarily to differences in the rate at which component letter pairs are matched.  相似文献   
243.
The correspondence between subjective and neural response to change in acoustic intensity was considered by deriving power functions from subjective loudness estimations and from the amplitude and latency of auditory brainstem evoked response components (BER). Thirty-six subjects provided loudness magnitude estimations of 2-sec trains of positive polarity click stimuli, 20/sec, at intensity levels ranging from 55 to 90 dB in 5-dB steps. The loudness power function yielded an exponent of .48. With longer trains of the same click stimuli, the exponents of BER latency measures ranged from -.14 for wave I to -.03 for later waves. The exponents of BER amplitude-intensity functions ranged from .40 to .19. Although these exponents tended to be larger than exponents previously reported, they were all lower than the exponent derived from the subjective loudness estimates, and a clear correspondence between the exponents of the loudness and BER component intensity functions was not found.  相似文献   
244.
Two experiments were performed employing acoustic continua which change from speech to nonspeech. The members of one continuum, synthesized on the Pattern Playback, varied in the bandwidths of the first three formants in equal steps of change, from the vowel /α/ to a nonspeech buzz. The other continuum, achieved through digital synthesis, varied in the bandwidths of the first five formants, from the vowel /æ/ to a buzz. Identification and discrimination tests were carried out to establish that these continua were perceived categorically. Perceptual adaptation of these continua revealed shifts in the category boundaries comparable to those previously reported for speech sounds. The results were interpreted as suggesting that neither phonetic nor auditory feature detectors are responsible for perceptual adaptation of speech sounds, and that feature detector accounts of speech perception should therefore be reconsidered.  相似文献   
245.
At a crosswalk on a busy street, a confederate, sketching a drawing or not, stood close or far from a pedestrian for 10 sec before the street light indicated “Walk.” In the first study, pedestrians were given the opportunity to subsequently help this confederate or another accomplice by calling attention to a dropped pen. In the second study, crossing speeds were timed and pedestrians were asked to record their mood and reactions to “another pedestrian,” who happened to be the confederate. These studies tested and found evidence for both cognitive and arousal explanations of reactions to spatial invasions. Cognitive and attributional theories imply that characteristics of the invader are important mediators of reactions to the invasion. The close nonartist was judged to be more inappropriate, produced faster escape speeds, and was helped less than the close artist or the far confederates. Arousal explanations imply that any invasion produces a generalized reaction which would be unrelated to characteristics of the invader. The other accomplice was helped less when the subject had been invaded and this reduction in helping was unaffected by the artist manipulation. These findings suggest a general arousal response to any invasion with a subsequent reliance on cognitive interpretations.  相似文献   
246.
Effects of aversive CSs upon dogs' instrumental avoidance responding were assessed as a function of the Pavlovian conditioning parameters using off-baseline (Experiment 1) and on-baseline (Experiment 2) conditioning procedures. In each experiment, three UCS intensitites (2, 6, and 10 mA) were crossed factorially with two CS-UCS intervals (10 and 90 sec) yielding six groups. After 4 days of conditioning, the CS-produced effects on avoidance were determined primarily by an interaction between Pavlovian procedure (off- versus on-baseline) and UCS intensity. With off-baseline conditioning, CS-produced facilitation of avoidance was an increasing function of the UCS intensity. However, with on-baseline conditioning, only the CS paired with weak UCS facilitated avoidance, and the CS paired with the strong UCS suppressed responding. This reversing parametric function poses problems for two-process motivational theories of avoidance.  相似文献   
247.
The central question at issue was the role of both infant and parent temperament in determining child adjustment at age 4. Within the conceptual framework of the New York Longitudinal Study (NYLS), both infant and parent temperament were assessed. Factor analyses yielded three comparable infant and parent temperament factors: Mood, Energy, and Consistency. Correlations with teacher ratings of child adjustment indicated the most significant relationship to be with the infant girls' Mood factor (comparable to the NYLS high-risk "difficult" infant factor). No infant factors were found to relate to boys' adjustment, while maternal Mood was significant across sexes. Indices of the temperamental similarity within families also revealed sex differences relative to adjustment, with similarity across all family members significantly related to adjustment for girls and boy-father dissimilarity significant for boys. Discussion centered around continuity-discontinuity issues relevant to sex differences.  相似文献   
248.
A series of studies investigating the psychometric and conceptual properties of the Survey of Ethical Attitudes (SEA), a paper-and-pencil measure of moral reasoning, is reported. The results of these studies indicate that the scale is clearly susceptible to the influence of response dissimulation in the form of both role-playing and impression management, and is also confounded with sources of stylistic variance in the form of social desirability. Previous proposals concerning the relationships among moral development, moral reasoning, and personality structure are reviewed in light of these findings, and an alternative conceptualization of the measure in terms of political and social attitudes is offered.  相似文献   
249.
250.
To improve career planning services for visually impaired persons, the career center at Florida State University developed a self-directed program. This article describes strategies for making career information materials and resources more accessible to the blind.  相似文献   
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