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221.
This paper covers mathematical, statistical, and experimental design considerations needed to design a computer system for EEG data acquisition, spectrum, and cross-spectrum analyses. A tutorial approach is used in which no formal proofs are offered. Conclusions are stated simply and in summary fashion, without justifying arguments. References to formal works are given. Conclusions about system design are discussed. Frequently encountered design issues are mentioned with various alternatives. 相似文献
222.
Charles W. Eriksen William P. O’hara Barbara Eriksen 《Attention, perception & psychophysics》1982,32(3):261-270
An account ofsame-different discriminations that is based upon a continuous-flow model of visual information processing (C. W. Eriksen & Schultz, 1979) and response competition and inhibition between the responses by which the subject signifies his judgment is presented. We show that a response signifyingsame will on the average be executed faster due to less priming or incipient activation of the competing response,different. In the experiment, the subjects matched letters on the basis of physical identity. The degree of priming ofdifferent responses on same trials and ofsame responses ondifferent trials was manipulated by an extraneous noise letter placed in the display. Latency for judgments onsame trials increased as the feature overlap of noise and target letters decreased. Latencies were shorter ondifferent trials when the noise letter was dissimilar to either target letter than when the noise letter was the same as one of the targets. These results were consistent with the response-competition interpretation. 相似文献
223.
J. E. Keith Smith 《Attention, perception & psychophysics》1982,31(2):183-189
In a recent paper (1981), Keren and Baggen proposed two new models for alphanumeric confusion data, based on Tversky’s (1977) feature model of similarity, and compared them with Luce’s (1963) biased choice model. On the basis of their data, they concluded that, although the choice model fit slightly better, their models were to be preferred on grounds of parsimony and interpretability. It is shown here that both of these models are special cases of the Luce model, so that the general Luce model will necessarily fit better. This leads to considerable reinterpretation of Keren and Baggen’s conclusions. Finally, better methods of estimating parameters and evaluating goodness-of-fit are suggested, taking advantage of this relation between the models. 相似文献
224.
225.
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
226.
R O Straub M S Seidenberg T G Bever H S Terrace 《Journal of the experimental analysis of behavior》1979,32(2):137-148
Three pigeons learned to peck four colors in a particular sequence, regardless of how these colors were positioned on four response keys and without feedback following each response. This demonstrates that serial learning is possible in subprimate animals. 相似文献
227.
A comparison was made of the scores of 171 Japanese boys and 156 Japanese girls, and of 204 English boys and 165 English girls, on the Visual Aesthetic Sensitivity Test. Also compared were 145 male and 163 female Japanese students, with 38 male and 73 female English students. Japanese children had scores significantly higher than English children, while Japanese students had scores significantly lower than English students. There was little evidence of age increments in score for either group of children. Difficulty levels of the 42 item-pairs were very similar in the two cultures, as were internal (split-half) reliabilities. It is concluded that cultural differences between the two countries, as far as visual aesthetic appreciation is concerned, seem at best minimal. 相似文献
228.
JOHN O. NELSON 《Philosophical Investigations》1979,2(1):1-8
We must agree, I think, with Frank Ebersole that there is something preposterous in supposing that the God of religious belief, the God who handed down tablets to Moses on Mt. Sinai, etc., should be proven to exist by the ontological argument. Indeed, when we place the one, the ontological argument, by the side of the other, the God of religious belief, there seems hardly to be any connection between them. But if we agree to this perception of things, what sense can we make of the ontological argument, for example, the “pull” that it sometimes exerts on us? 相似文献
229.
There is evidence that cardiac arrhythmias are partially of CNS origin, and that certain drugs affect arrhythmia, both positively and negatively, through CNS action. We hypothesized and confirmed that chlordiazepoxide diminished the well-established incidence of arrhythmias (A-V blocks and nodal escapes) in five nervous pointer dogs. It is known that this drug normalizes behavior and aids in the bar-pressing performance of nervous dogs. Nervous dogs tend to have low heart rates (HRs) while normals have higher HRs. Chlordiazepoxide increased HRs in our five nervous dogs, and we postulated that HR increase would be less or none in normals. This was confirmed in a later study of five normals. A further study of eight normal dogs and eight nervous dogs essentially reproduced these findings, suggesting the possibility that the slow heart rates and the behavioral abnormality have a common basis, expected to be some CNS biochemical lesion. 相似文献
230.
When head-movement parallax functioned as the sole veridical distance cue during exposure to spectacles that altered the eyes’ oculomotor adjustments, sizable adaptation was obtained. This result showed that a discrimination of the distances of 60 and 30 cm can be based on head-movement parallax. Using adaptation in demonstrating that head-movement parallax can serve as a distance cue circumvents the problem that the presence of accommodation normally presents when such a demonstration is attempted. The usual contamination of head-movement parallax with accommodation is avoided, because accommodation is altered by the spectacles and does pot function as a veridical cue along with head-movement parallax. 相似文献