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271.
Robert S. Burke 《Behavior research methods》1988,20(2):171-174
A technical issue in auditory spatial attention research is how best to provide low-cost, accurate control of the frequency, duration, and location of acoustic signals. Three solutions to the problem are compared: use of the internal oscillator of the Apple lIe, use of a Mountain A/D+D/A card, and use of an external oscillator chip. The unique advantages and drawbacks of each system are discussed. All share some common problems of external speaker interface, timing control, and interface with the software. Hardware and software solutions implemented on the Apple-Psych system are discussed, along with data that demonstrate the precision control achieved with the system. 相似文献
272.
Daniel S. Lordahl 《Behavior research methods》1988,20(2):221-223
Difficulties with the Microsoft BASIC function for generating random numbers (RND) are cited and new problems reported. Fixes are suggested that allow use of some of the speed of the original function and that produce greatly improved pseudorandom numbers. A published generator is combined with the RND function as a compromise solution. 相似文献
273.
We outline a BASIC program and subsidiary machine language timing routines that enable the Apple II series of computers to be employed as control devices for the tachistoscopic presentation of 35-mm slides and the collection of response latencies. The program is functional for experiments that require pictorial stimuli to be presented in up to three separate fields, with precise display times, precise interstimulus and intertriai intervals, and the collection of manual or vocal reaction times with millisecond accuracy. The major advantages of this system are that initial setup costs are substantially lower than those for other similar systems (e.g., Loftus, Gillispie. Tigre, & Nelson, 1984) and that user customization of the program may be accomplished by anyone possessing rudimentary knowledge of the BASIC programming language. 相似文献
274.
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276.
Thirty children and 5 adults participated in two experiments designed to compare visual processing in normal and reading disabled children. The children were aged 8, 10, and 12 years. In Experiment 1, subjects were asked to detect the temporal order of two briefly presented stimuli. In Experiment 2, subjects sorted cards containing bracket stimuli that did or did not produce perceptual grouping effects. Poor readers required more time to make accurate temporal order judgments and showed stronger perceptual grouping effects. For both good and poor readers, the amount of time necessary to make a correct temporal order judgment decreased, and perceptual grouping effects became weaker with age. However, the magnitude of the difference between the groups did not lessen with age. These results suggest that there are visual processing differences between good and poor readers that do not appear to correct by age 12. 相似文献
277.
Differences in school behavior and achievement between students from intact, reconstituted, and single-parent families were analyzed. Students from intact two-parent families had fewer absences and tardies, higher grade point averages, and fewer negative and more positive teacher behavioral ratings than did those from reconstituted and single-parent families. 相似文献
278.
Two projective techniques were employed to explore the psychological characteristics of teenage mothers who were found, in a previous study, to have experienced more traumatic childhoods than the nonmother control group. Part I, presented here, investigated ego development using the Loevinger Sentence Completion Test. (Part II, responses to a set of TAT cards, will appear in a subsequent issue of Adolescence.) In comparison with the nonmothers, teenage mothers demonstrated more mature ego development. This is in distinct contrast with most reports in the literature, and the ramifications of these results are discussed. In addition, content analyses of the responses to the Sentence Completion Test confirm the highly involved mother-daughter and negative father-daughter relationships found in the previous study with this sample. 相似文献
279.
This paper deals with girls aged 13 to 21 who have run away from home. Social workers who work with such girls point out that they are not a homogeneous population and that their motives can be very different. This study divides their motives for running away into two types, "running from" and "running to," and describes the specific personality traits associated with each. Findings indicate that girls who "run to" are younger, more impulsive, have an internal locus of control and a history of more runaways and longer periods of staying away from home. Girls who "run from," on the other hand, are older, more reflective, have an external locus of control and a history of fewer runaways and shorter periods away from home. 相似文献
280.