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81.
Conventional procedures do not provide a practical method for the administration of volatile anesthetics such as halothane to rats while they are undergoing stereotaxic surgery. This paper describes a device which meets this need and which is easy and inexpensive to construct. A two-piece cylinder cut from the mouth of a polyethylene bottle forms a closed system around the muzzle of a rat and does not interfere with the stereotaxic apparatus or with the operation itself. The cylinder is attached to any standard device for the dispension of volatile anesthetics. The immediate advantage is that behavioral assesaments can be made relatively soon after surgery. 相似文献
82.
The plastic barrel suit provides complete protection of chronically implanted fistulas and electrical connectors. The lost time, expense, and the frustrations of having these devices damaged was avoided. 相似文献
83.
Stephen R. Schroeder 《Attention, perception & psychophysics》1970,7(2):121-124
Human Ss, when given a discrimination task whose stimuli varied in dimension and relevance, always chose and ftxated more frequently the stimulus they had been reinforced for choosing. Decreasing the brightness reduced the choice and ftxation preference for form stimuli over line stimuli and raised total ftxation frequency. Ss decreased fixation frequency to discriminanda with practice. 相似文献
84.
Subjects viewed slides of the Rorschach cards while listening to heart sounds that were supposedly but not actually their own. For some of the subjects the heart rate increased when they were exposed to the five achromatic cards and for some subjects the heart rate increased when they were exposed to the five chromatic cards. In addition, some subjects were told that increased heart rate was a sign of mental health (positive condition), and some that the increased heart rate was a sign of mental abnormality (negative condition) Since the heart-rate increase (behavior) and Rorschach cards associated with the increase (attitude object) are connected by a positive causal relation, triadic theory predicts that the sign of the heart-rate increase should generalize to the associated cards (i e, be positive in the positive condition and negative in the negative condition) An analysis of variance revealed such an overall significant effect Closer examination of the data, however, revealed that the triadic effects were not unambiguously occurring when the increased heart rate was associated with achromatic cards It was suggested that in this condition the unique characteristics of the cards facilitated the generation of complicating anxiety. Supportive data for this interpretation were offered 相似文献
85.
86.
Past studies have shown that stuttering is eliminated when speech is synchronized with a metronomic beat, but the speech sounds artificial. The present study investigated the effect of increasing the duration of these individual stimulus beats with the stimulus-off period constant at 1 sec. When subjects were instructed to speak during the stimulus-on period, stuttering was an inverse function of stimulus duration, indicating that the known metronome effect on stuttering is one point on a continuum of effective rhythm procedures. The "naturalness" of speech increased as the stimulus duration increased up to durations of about 2 sec, and then decreased. At optimal values, stuttering was greatly reduced and naturalness and rapidity of speech were retained. These optimal values effectively controlled stuttering in a field test that used two types of specially designed portable instruments, one of which produced a tactual stimulus and the other an auditory stimulus. 相似文献
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Stephen Arnold Weinstein 《Integrative psychological & behavioral science》1967,2(2):118-126
The effects of varying CO2 concentration, and intervals between CO2 presentations, were determined from the performance by five pigeons of a learned motor act which eliminates CO2 from the inspired air. The length of time from the onset of an externally-produced increase in inspired CO2 to the performance of the learned motor response terminating the CO2 presentation was inversely related to the CO2 concentration presented (3 per cent and 5 per cent) and directly related to the inter-trial interval (3 minutes and 1.5 minutes). Chemoreceptors on the ventrolateral surfaces of the medulla are postulated to be the initial site of stimulation in the chain of events leading to the behavioral bioregulation of inspired CO2 concentration. 相似文献
90.