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221.
The purpose of this research was to examine the relationship between parents' perceptions of marital satisfaction and family stress and their third grade children's classroom behavior. Twenty-one married couples completed questionnaires during home visits. Behavior observations were made from videotapes of children recorded in their classroom during lunch and group academic periods on each of three days. Frequencies of peer interactions, solitary behaviors, and teacher interactions were coded. Regression analyses showed that mothers' level of marital satisfaction (but not fathers') predicted their children's frequency of peer interactions during lunch. Fathers' level of perceived family stress (but not mothers') predicted their children's frequency of peer interactions during lunch. Neither measure for either parent was related to the frequency of peer interactions, solitary behaviors, or teacher interactions observed during the academic sessions. These findings highlight the importance of assessing the potential differential relation of parent variables to children's trans-situational behaviors, and the examination of these variables in relation to different social-environmental contexts in which children participate outside the home.  相似文献   
222.
Systems of care for children with serious emotional disturbance and their families have generally lacked intensive community-based programs. We describe three types of newly established community-based programs in New York State and present a general evaluation plan for determining which programs work for various children and their families. The three community-based programs are Intensive Case Management, Family-Based Treatment, and Family-Centered Intensive Case Management. Process and outcome evaluations are being conducted for each of these programs. These evaluations make use of common intake and termination instruments, based on a minimum data set, standardized assessment instruments, and a common logic model, thus facilitating the comparison of findings across evaluations.  相似文献   
223.
A tether system has been developed for continuous monitoring of blood pressure in the micropig. The micropig is a suitable model for blood-pressure research because of the similarity of its cardiovascular system to that of humans and because of its sensitivity to high sodium intake. The system consists of a metal boom, attached via a universal joint to a wall 6 ft above floor level, that extends horizontally to the center of the enclosure. A fluid and electronic swivel affixed to the boom is connected to a flexible, hollow, metal tether that descends to a vest worn by the micropig. The vest contains a pressure transducer to which an indwelling arterial catheter is connected via a stopcock. The transducer cable and an infusion line ascend through the interior of the tether to the swivel. The system remains in equilibrium through a system of pulleys and counterweights. Continuous, 24-h recording shows a diurnal variation characterized by higher heart rate but lower blood pressure during the day than at night. The system has been found to be effective for continuous studies over intervals of a month or more.  相似文献   
224.
Picture Perception Lab (PPL) is a program for picture perception experiments. PPL capitalizes on the sophisticated drawing software available for the Macintosh computer by allowing the user to create stimulus images by using almost any drawing package. Through a series of user-friendly dialog boxes, PPL enables even nonprogrammers to develop, quickly and easily, tachistoscopelike vision experiments. The program allows a wide variety of experimental designs. Image exposure durations and subjects’ reaction times are precisely monitored with millisecond timing functions. Each image is drawn on the screen in a single 60-Hz refresh.  相似文献   
225.
Pigeons’ pecking has long been a subject of interest in behavioral research, with the response typically being viewed as unitary. Recent experiments done with computer-controlled devices have revealed that this response is at least bipartite in character, with beak opening and response location (head transport) as its components. In addition, experimental work has demonstrated that these response components may be separately influenced and controlled by respondent and operant conditioning procedures. The detailed topographic analysis and technology that have emerged may provide a background for similar work with other behavioral systems.  相似文献   
226.
Utrecht Biophysics Research Institute, Rijksuniversiteit Utrecht, Utrecht, The Netherlands Subjects were asked to match the speeds of two moving random-dot patterns seen through circular apertures. The speed of one pattern that moved horizontally toward the right of a computer screen changed continuously. The speed of this pattern represented the target. It was to be matched with the speed of the second pattern, which moved in the opposite direction. The subject controlled the speed of the second pattern by means of an isometric joystick. The distance between the apertures on the screen as well as the subject’s distance from the screen served as experimental parameters. In this way, the effects of both spatialand temporal transients of pattern speed on human tracking performance were studied. To avoid anticipation by the subject, the amplitude and the frequency of the target pattern speed changed pseudorandomly. The accuracy with which the subject performed the matching task was influenced by the mean pattern speed and the parameters of the visual field. Within lower velocity ranges, the subject’s sensitivity to the instantaneous speed differences varied according to Weber’s law. The cross-correlation of the velocity time courses decreased when the mean speed of the target pattern was increased. Two stimulus parameters had a strong influence on the modulation of the correlation value: (1) the angular size of the stimulus on the retina and (2) the retinal eccentricity of the stimulus.  相似文献   
227.
Working in the fragment of Martin-Löfs extensional type theory [12] which has products (but not sums) of dependent types, we consider two additional assumptions: firstly, that there are (strong) equality types; and secondly, that there is a type which is universal in the sense that terms of that type name all types, up to isomorphism. For such a type theory, we give a version of Russell's paradox showing that each type possesses a closed term and (hence) that all terms of each type are provably equal. We consider the kind of category theoretic structure which corresponds to this kind of type theory and obtain a categorical version of the paradox. A special case of this result is the degeneracy of a locally cartesian closed category with a morphism which is generic in the sense that every other morphism in the category can be obtained from it via pullback.The financial support of the Royal Society in London is gratefully acknowledged.  相似文献   
228.
Context effects in stroop-like word and picture processing   总被引:7,自引:0,他引:7  
Presents a series of 6 experiments in which Stroop-like effects were generated by modally pure color-color, picture-picture, and word-word stimuli instead of the usual modally mixed color-word or picture-word stimuli. Naming, reading, and categorization tasks were applied. The Stroop inhibition was preserved with these stimuli but unexpectedly showed a semantic gradient only in the naming and not in the reading task. Word categorizing was slower and more interference prone than picture categorizing. These and other results can be captured by a model with two main assumptions: (a) semantic memory and the lexicon are separate, and (b) words have privileged access to the lexicon, whereas pictures and colors have privileged access to the semantic network. Such a model is developed and put to an initial test.  相似文献   
229.
Effects of stimulus movement on learning, transfer, matching, and short-term memory performance were assessed with 2 monkeys using a video-task paradigm in which the animals responded to computer-generated images by manipulating a joystick. Performance on tests of learning set, transfer index, matching to sample, and delayed matching to sample in the video-task paradigm was comparable to that obtained in previous investigations using the Wisconsin General Testing Apparatus. Additionally, learning, transfer, and matching were reliably and significantly better when the stimuli or discriminanda moved than when the stimuli were stationary. External manipulations such as stimulus movement may increase attention to the demands of a task, which in turn should increase the efficiency of learning. These findings have implications for the investigation of learning in other populations, as well as for the application of the video-task paradigm to comparative study.  相似文献   
230.
The relationship between amphetamine-induced stereotyped behavior and a neuroendocrine index of arousal, plasma corticosterone (CCS), was investigated. 6-Hydroxydopamine lesions of the caudate-putamen, which produced dopamine depletions of 60%, blocked stereotypy and prolonged the elevation in corticosterone associated with d-amphetamine treatment (5 mg/kg). Similar dopamine depleting lesions of the nucleus accumbens, which attenuated the locomotor, but not the stereotypic, response to AMPH did not have this effect on CCS. This pattern of results supports the hypothesis that stereotypy has a coping function which may serve to alter arousal and further suggests important differences between the nigrostriatal and mesolimbic dopamine projections in modulating the responsiveness of the neuroendocrine system. These results have implications for understanding the function of behavioral stereotypies common to a number of psychopathological conditions, including schizophrenia and childhood autism.  相似文献   
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