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91.
James E. Skinner Stewart G. Wolf J. Yasha Kresh Igor Izrailtyan J. A. Armour Ming-he Huang 《Integrative psychological & behavioral science》1996,31(2):122-146
The neural organization that determines the specific beat-to-beat pattern of cardiac behavior is expected to be demonstrated in the independent regulation of the RR intervals (chronotropy) and the corresponding QT subintervals (inotropy), as the former defines the rate of contraction and the latter has a linear negative correlation with the peak pressure inside the contracting ventricular muscles. The neurons of the isolated cardiac nervous system, many of which are located in the fat-pads of the heart, exhibit the same types of mechanical and chemical receptors and the same types of cholinergic and noradrenergic effectors as those found in the neural superstructure. In the surgically isolated and perfused rabbit heart we studied the responses of the QT and RR intervals evoked by block of coronary blood flow. We found that if we separated each RR cycle into QT and RR-QT components, then the dynamics of variation for each subinterval series often had the same fractional number of degrees of freedom (i.e., chaotic dimensions), a finding which suggests they are both regulated by the same underlying system. The ischemia/anoxia evoked transient dimensional increases and separations between the two subinterval series that, after the temporary divergence, reconverged to having the same lower value. The dimensional fluctuations occurred repeatedly and preceded or coincided with alterations in the magnitude and sign of the slope of QT vs RR-QT. We interpret the dimensional fluctuations of the two subinterval series as correlates of adaptation-dependent self-organization and reorganization in the underlying intrinsic cardiac nervous system during accumulating ischemia/anoxia. Such attempts at functional reorganization in this simple neurocardiac system may explain the transient dimensional changes in the RR intervals that precedes by 24 hrs the occurrences of fatal ventricular fibrillation in high-risk cardiac patients. 相似文献
92.
Feinstein Robert Gooden Brett A. Wolf Stewart 《Integrative psychological & behavioral science》1975,10(2):102-111
Integrative Psychological and Behavioral Science - Repeated EEG and ECG monitoring during sleep was carried out in two subjects with ischemic heart disease and one presumably healthy control. All... 相似文献
93.
James D. Barnard Edward R. Christophersen Montrose M. Wolf 《Journal of applied behavior analysis》1974,7(3):481-481
Applied researchers increasingly report the use of paraprofessionals to implement key program components. However, despite such apparent advantages as increased availability and lower salaries, problems in maintaining acceptable levels of on-the-job performance in these workers have been reported. This study assessed the effects of a supervisory package on the work behavior of five paraprofessional tutors in a remedial reading program. The package consisted of written handouts and instructions, tests of tutor understanding, a video tape, mention of tutor performance by supervisors, and publicly posted feedback on work performance. One randomly chosen tutor received feedback each day on (1) his degree of completeness in tutoring one student's answers to comprehension-check questions, (2) his accuracy in tabulating that student's data sheet, and (3) his promptness in beginning the first student's tutorial session. The supervisory package produced marked improvement in completeness, some improvement in accuracy, but no improvement in promptness. Application of the supervisory package seemed practical, as an average of nine daily tutorial sessions (approximately 270 min of tutoring) required a total daily average of only 28 min of supervision. It was concluded that completeness performance by nondegreed, paraprofessional tutors was closely related to the extent to which they were supervised. Despite the fact that no improvement was observed in tutor promptness, and only partial improvement was observed in tutor accuracy, the improvement to near-perfect levels in tutor completeness suggests that further research is warranted to develop supervisory packages that might ensure the reliable and efficient use of paraprofessional workers. 相似文献
94.
Thomas Wolf 《Journal of psycholinguistic research》1976,5(2):143-171
The author, a professional flutist and psychologist, interviewed four pianists noted for their sight-reading abilities. The results of the interviews are considered from several points of view. Sight-reading is analyzed as a problem in pattern recognition: a movement from a sonata by Handel is used to illustrate the principle of scanning for familiar patterns. The close relationship between musical sight-reading and the reading of conventional texts is also suggested. Finally, drawing on the findings of other studies, a cognitive model of musical sight-reading is proposed. The schematic model of interlocking information-processing systems explains the differences between skilled and unskilled sight-readers; it also explains why some experienced, professional musicians are poor sight-readers. Verification of the model is provided in an additional section in which conversations with unskilled sight-readers are reported. 相似文献
95.
Effects of four noise conditions on arithmetic performance 总被引:1,自引:0,他引:1
96.
A wide variety of complex waveforms can be generated by approximating the desired analog waveform from an array of digital values. Some basic properties of these digital approximations are discussed in terms of pulse amplitude modulation and sampling theory. The waveforms are generated by transferring the digital values to a digital-to-analog converter followed by a low-pass filter. This usually requires the dedicated use of a computer. We have built a device, incorporating solid state memory, that can store, time, and transfer previously computed digital values, so that a computer is no longer necessary to generate the waveforms. Specifications of the digital-to-analog converter and appropriate settings of the filter are discussed, along with a simplified procedure for calculating waveforms that have line spectra. An adaptation of this procedure enables the device to be used as a high-speed programmable pure-tone source. 相似文献
97.
This study examined 40 preschool children's understanding of the word touch. 24 drawings were presented one at a time to each child, and the children were instructed to describe each of the drawings and to classify them into drawings portraying touch or drawings showing no touch. 20 undergraduates were also interviewed. The same procedure was used, but in addition the undergraduates were asked to predict how preschool-age children would do on the same task. The results showed several ways in which the children's understanding of the word touch differed from that of an adult. 相似文献
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