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171.
A running-wheel movement-detection method is described for use with a modified 1350 Commodore mouse and a Commodore 64, is described. The movement-detection method allows for the detection of partial revolutions and direction of movement, but requires no interface equipment. The modified running wheel is discussed as a new technique that may be useful for bridging empirical and theoretical differences between free-operant and discrete-trial runway procedures. 相似文献
172.
Bruno H. Repp 《Attention, perception & psychophysics》1992,51(1):14-32
This study investigated whether the apparent completeness of the acoustic speech signal during phonemic restoration derives from a process of auditory induction (Warren, 1984) or segregation, or whether it is an auditory illusion that accompanies the completion of an abstract phonological representation. Specifically, five experiments tested the prediction of the auditory induction (segregation) hypothesis that active perceptual restoration of an [s] noise that has been replaced with an extraneous noise would use up a portion of that noise’s high-frequency energy and consequently change the perceived pitch (timbre, brightness) of the extraneous noise. Listeners were required to compare the pitch of a target noise, which replaced a fricative noise in a sentence, with that of a probe noise preceding or following the speech. In the first two experiments, a significant tendency was found in favor of the auditory induction hypothesis, although the effect was small and may have been caused by variations in acoustic context. In the following three experiments, a larger variety of stimuli were used and context was controlled more carefully; this yielded negative results. Phoneme identification responses collected in the same experiments, as well as informal observations about the quality of the restored phoneme, suggested that restoration of a fricative phone distinct from the extraneous noise did not occur; rather, the spectrum of the extraneous noise itself influenced phoneme identification. These results suggest that the apparent auditory restoration which accompanies phonemic restoration is illusory, and that the schema-guided process of phoneme restoration does not interact with auditory processing. 相似文献
173.
Utrecht Biophysics Research Institute, Rijksuniversiteit Utrecht, Utrecht, The Netherlands Subjects were asked to match the speeds of two moving random-dot patterns seen through circular apertures. The speed of one pattern that moved horizontally toward the right of a computer screen changed continuously. The speed of this pattern represented the target. It was to be matched with the speed of the second pattern, which moved in the opposite direction. The subject controlled the speed of the second pattern by means of an isometric joystick. The distance between the apertures on the screen as well as the subject’s distance from the screen served as experimental parameters. In this way, the effects of both spatialand temporal transients of pattern speed on human tracking performance were studied. To avoid anticipation by the subject, the amplitude and the frequency of the target pattern speed changed pseudorandomly. The accuracy with which the subject performed the matching task was influenced by the mean pattern speed and the parameters of the visual field. Within lower velocity ranges, the subject’s sensitivity to the instantaneous speed differences varied according to Weber’s law. The cross-correlation of the velocity time courses decreased when the mean speed of the target pattern was increased. Two stimulus parameters had a strong influence on the modulation of the correlation value: (1) the angular size of the stimulus on the retina and (2) the retinal eccentricity of the stimulus. 相似文献
174.
In 1977 sex-trait stereotypes in Norway were measured at the young adult level and at the level of five-year-olds. At the young adult level the Adjective Check List was used, and the results were analysed according to an affective meaning scoring system, and a scoring system based on Transactional Analysis. The instrument used for children was a picture-story technique (Sex Stereotype Measure II). Persistence and change in sex-trait stereotypes were examined by replicating the study in 1987. Quantitatively, young adults' sex-trait stereotypes seemed to have changed little during the last decade, but qualitative analyses indicated that stereotypes have changed in the direction of greater favourability, activity and strength towards women and in the reverse direction towards men. The children in the 1987 sample expressed less stereotype knowledge than children in the 1977 sample concerning traits which traditionally have been ascribed to men. 相似文献
175.
Massey on fallacy and informal logic: A reply 总被引:1,自引:0,他引:1
Ralph H. Johnson 《Synthese》1989,80(3):407-426
176.
DBA/2J mice were monaurally or binaurally tested for susceptibility to sound-induced seizure. Two seconds following the beginning of running, one group of binaurally tested mice had acoustic stimulation interrupted for 15 s. These mice later seized when the stimulation was readministered. Their seizure progression closely resembled the behavior exhibited by noninterrupted binaurally stimulated mice and did not shift to the biphasic motor pattern of monaurally stimulated subjects. We conclude that the single burst of running of a binaurally tested mouse is qualitatively different from either of the two bursts of running exhibited by monaurally tested mice. 相似文献
177.
The relationship between amphetamine-induced stereotyped behavior and a neuroendocrine index of arousal, plasma corticosterone (CCS), was investigated. 6-Hydroxydopamine lesions of the caudate-putamen, which produced dopamine depletions of 60%, blocked stereotypy and prolonged the elevation in corticosterone associated with d-amphetamine treatment (5 mg/kg). Similar dopamine depleting lesions of the nucleus accumbens, which attenuated the locomotor, but not the stereotypic, response to AMPH did not have this effect on CCS. This pattern of results supports the hypothesis that stereotypy has a coping function which may serve to alter arousal and further suggests important differences between the nigrostriatal and mesolimbic dopamine projections in modulating the responsiveness of the neuroendocrine system. These results have implications for understanding the function of behavioral stereotypies common to a number of psychopathological conditions, including schizophrenia and childhood autism. 相似文献
178.
D H Foster M Ferraro 《Journal of experimental psychology. Human perception and performance》1989,15(4):771-784
Visual processing was investigated in judgments of relative line position. Stimulus continua were generated by bisecting a straight line and displacing the segments. Experiment 1 measured discrimination of pairs of longitudinally displaced segments at equal steps along the continuum. At long (2 s) durations discrimination fell smoothly, but at short (100 ms) durations it was sharp-peaked. In Experiment 2 the short-duration stimuli were labeled with subsets of the labels no gap, just a gap, and more than just a gap. Theoretical discrimination performances were computed and the one based on no gap and just a gap closely fitted observed performance. Experiments 3 and 4 were similar to 1 and 2, with lateral replacing longitudinal displacement. Similar "categorical" performance was obtained. It was concluded that there are discrete mechanisms for early detection of relative line position and that 2 labels can be used to characterize performance in each direction. 相似文献
179.
M H Erdelyi J Finks M B Feigin-Pfau 《Journal of experimental psychology. General》1989,118(3):245-254
We explored Roediger and Payne's proposal that response bias does not affect recall performance and that it is therefore not necessary to control for response productivity in recall studies. Two initial experiments, contrary to expectation, corroborated Roediger and Payne's findings: Forced recall did not produce more correct recalls than free recall, even though forced recall produced substantially more false alarms than did free recall. However, in succeeding experiments involving pictorial and verbal stimuli, reliable response-bias effects on recall were demonstrated. The stimuli yielding response-bias effects were those associated with higher probabilities of being guessed by chance. In addition, some of the data suggest that processing-bias effects (differential retrieval effort) may be unintentionally induced by instructions and may significantly affect recall memory. Consequently, it is necessary to assess or to control response-bias effects and, possibly, processing-bias effects in recall experiments in which level of recall is of interest. 相似文献
180.
The responses toward denatonium saccharide and quinine by three rodent species differ from those exhibited by humans. This study measured the relative aversiveness of these two compounds in grasshopper mice (Onychomys leucogaster) to determine if this species responded similarly to or differently from these other rodents. In a choice test, the mice clearly preferred quinine over denatonium saccharide at concentrations of 1/10,000 and 1/50,000, but only marginally preferred quinine at a concentration of 1/1000. When denatonium or quinine was paired with toxicosis, both suppressed drinking at concentrations from 1/10,000 to 1/50,000, but only denatonium suppressed drinking at 1/100,000. Neither compound suppressed drinking at 1 part in million. Grasshopper mice perceived denatonium saccharide as more aversive than quinine in both experiments. Such a response resembled the behavior of humans more than that of the other three rodents previously tested. 相似文献