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921.
J Cranney M E Cohen H S Hoffman 《Journal of experimental psychology. Animal behavior processes》1985,11(1):112-119
In laboratory rats (as in humans) a low-intensity tone that precedes a high-intensity burst of noise by approximately 100 ms can reduce the amplitude of the startle reaction elicited by the burst of noise. A series of four experiments with rats investigated the relation between the inhibitory effects of tonal frequency change and the length of the silent period (gap) preceding it. The major findings were the following: (a) A gap in an otherwise continuous pure tone inhibited startle when the gap occurred approximately 100 ms prior to the noise burst. (b) Although an increase in gap duration increased the inhibition afforded by the gap, the maximum inhibition was yielded by gaps of 100 ms and greater; this maximum was equivalent to the inhibition yielded by the presentation of a postgap tone alone. (c) A shift in tonal frequency across a 10-ms gap yielded more inhibition than did the same gap with no frequency shift; again the shift yielded equivalent inhibition to the presentation of the postgap tone alone. (d) An increase in the frequency shift increased inhibition when the shift occurred across a 10-ms gap, but not when the shift occurred across a 100-ms gap. 相似文献
922.
Observers detected a briefly flashed target letter embedded in word, pronounceable nonword, and unpronounceable nonword contexts. The word context facilitated perception under both holistic and analytical processing strategies; the facilitative effect was enhanced when processing was analytical. 相似文献
923.
P J Urcuioli 《Journal of experimental psychology. Animal behavior processes》1985,11(4):502-519
Pigeons were trained on matching-to-sample (MTS) with differential sample-response requirements that were identical with respect to two pairs of sample stimuli but were either correlated or uncorrelated with correct choice. Experiment 1A showed that birds in the uncorrelated condition were slower to reach criterion levels of accuracy than birds in the correlated condition in spite of their equivalent sample discriminations. However, correlated birds were more disrupted in their matching performances than the uncorrelated birds when subsequently switched to nondifferential sample-response requirements (Experiment 1B). Experiment 2 showed that differential sample behaviors also generated higher levels of accuracy on delayed MTS when correlated with choice, and that accuracy in this condition did not differ as a function of whether the samples were hues or lines. Sample dimension did affect memory performance, on the other hand, in the uncorrelated condition. In Experiment 3, reversing differential sample-response requirements for one pair of samples substantially reduced matching accuracy in the correlated group but had almost no effect in the uncorrelated group. These findings demonstrate that differential sample behaviors directly control pigeons' matching performances and also overshadow conditional stimulus control by the samples when these behaviors are predictive of correct choice. The facilitation in matching produced by differential sample behaviors apparently arises from the additional cue these behaviors provide, not because they enhance sample discriminability. 相似文献
924.
925.
926.
The purpose of this study was to determine the extent to which stutters manipulate vowel duration to achieve fluency after participating in Precision Fluency Shaping. Nine stutterers who read an all-voiced sentence fluently before and after therapy were selected for study. Wide-band spectrograms were made of the initial phrase of the sentences, and vowel durations were computed. Results indicated that extended vowel durations were characteristic of the fluency of stutterers posttherapy. The subject that had the highest rate of disfluency after therapy also had the shortest vowel durations. Clinical implications concerning the importance of speech rate during carryover practice are made. 相似文献
927.
928.
The Extended Objective Measure of Ego Identity Status (EOM-EIS) was examined for reliability and validity among early/middle adolescent subjects. The EOM-EIS represents a combination of the Objective Measure of Ego Identity Status and a structured interview of identity status. The instrument was designed to measure ego identity with regard to occupational, religious, political, philosophical, and social contexts along ideological and interpersonal dimensions. A total of 467 students aged 12 to 18 (median = 15.73) responded to the instrument. In general the results from the analyses of reliability, validity, demographic characteristics, and psychosocial maturity yielded results which parallel the theoretical framework and the results from college-aged subjects. 相似文献
929.
Using a backward-masking paradigm with a bias-free and ceiling-free psychophysical task, we tested hypnotized and control subjects for speed of visual information processing. Approximately half of each group received visual imagery suggestions in an attempt to influence attention. Imagery produced no significant differential effect. Although an absence of a hypnotizability-performance relationship was in keeping with findings of a previous study, those subjects in the present study who performed under hypnosis were, as a group, significantly superior to the other subjects in speed of information processing. 相似文献
930.
E M Weiler B Katbamna N Nileshwar A Dell'Aira 《The Journal of general psychology》1987,114(4):411-421
The present study examined the similarities between four auditory adaptation techniques to determine whether the effects were correlated. The four adaptation techniques compared were: Simultaneous Dichotic Loudness Balance technique (SDLB; Hood, 1950), Magnitude Estimated Binaural technique (MEB; Botté, Canévet, & Scharf, 1982), Magnitude Estimated Monaural technique, (MEM; Weiler, Sandman, & Pederson, 1981), and the Monaural Reaction Time technique (RT; Davis & Weiler, 1976). Results did not show significant correlations between the four techniques, except (r = 0.39) between MEB and MEM procedures. This correlation was much less than the reliability of the measures would allow (r = 0.98 and r = 0.99, respectively). Thus, it appears that the different methods either produced different adaptation effects or measured different aspects of auditory adaptation. The normal ear apparently shows several forms of adaptation, which reduces the perceptual strength of a continuing stimulus, in favor of an intermittent, less redundant one. 相似文献