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931.
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936.
Forty normal male volunteers were randomly assigned to one of four experimental conditions and instructed to raise and lower their systolic blood pressure. Subjects received either beat-to-beat feedback contingent on pressure changes, noncontingent beat-to-beat feedback, noncontingent feedback presented randomly with respect to the occurrence of each heart beat, or instructions alone. The order of increase and decrease trial blocks was counterbalanced across groups. Subjects receiving contingent feedback were monetarily rewarded for appropriate pressure changes. Subjects receiving noncontingent feedback received rewards and feedback equal to the mean received by the contingent group. Subjects in the instructions-only condition were also paid this bonus but were informed of their earnings only at the conclusion of the experiment. Results indicated that in the presence of instructions, feedback, whether contingent or noncontingent, added little to subjects' ability to control pressure during a single session. Theoretical and clinical implications are discussed.  相似文献   
937.
Auditory intensity in the conditioning treatment of enuresis nocturna was examined in a study by Young and Morgan (1973a). In their study of three alarm intensities, no significant differences either in terms of treatment efficacy or of subsequent relapse were found. For both theoretical and practical reasons, the finding of no differences in treatment parameters as a function of varying alarm intensities is puzzling. In learning theory terms, a very intense UCS (bell or buzzer) would be expected to lead to more rapid acquisition of dryness (conditioned response) than a less intense UCS. Learning theory notwithstanding, the depth of somnolence of the enuretic child is legend. Not only are testimonials from parents regarding difficulty in arousal of their bedwetting child commonly elicited, but the literature on causes and treatment of bedwetting is replete with evidence of a deep-sleep enuresis syndrome (Bostock, 1962). It has been demonstrated by Finley (1971) and Di Perri and Meduri (1972) that the arousal threshold of enuretic children is abnormally high compared to nonenuretic children. The failure of the enuretic to awaken to the presentation of a bell (UCS) is frequently cited as responsible for unsuccessful bell-and-pad conditioning (Browning, 1967). Young and Morgan (1973b) in their study on rapidity of response to the conditioning treatment for enuresis found that one treatment problem most significantly related to slow responders was failure of the alarm stimulus to awaken the child. For those unfamiliar with the literature, the Young and Morgan (1973b) finding appears particularly surprising when one considers that they employed as their alarm UCS “...a powerful auditory stimulus...” (p. 490).Because of these important theoretical as well as practical concerns, an attempt was made to examine the effect of two auditory intensities on treatment and relapse parameters in the conditioning of enuresis nocturna.  相似文献   
938.
Animals made vicious with bilateral ventromedial hypothalamic lesions had bipolar electrodes implanted unilaterally in the lateral septum, medial septum, or cingulate cortex. Four days later, the animals' reactivity and aggressiveness were evaluated 5 min before, during, and 5 min after stimulation at 20 micronA (60 Hz, sine wave). Lateral septal stimulation suppressed reactivity and aggressiveness by almost 80% compared with pre- and poststimulation levels. Stimulation of neither the cingulate cortex nor the medial septum produced a change reliably different from that seen in unstimulated control animals. Further tests with stimulation of the lateral septum at the 20-micronA level showed that neither rewarding self-stimulation nor disruption of ongoing water drinking was produced. These results are congruent with evidence from lesion studies that the lateral septum normally acts to suppress reactivity and aggressiveness in the rat; they do not support previous suggestions that the medial septum is involved in the modulation of these behaviors.  相似文献   
939.
Two experiments measured changes in binocular eye alignment from 1- to 6-month-old human infants. In Experiment 1 changes in binocular eye alignment were recorded from 1, 2, and 3 month olds using corneal photography. A luminous target was moved along the infant's midline at one of two constant speeds. Infants at all three ages showed some evidence of appropriate changes in binocular eye alignment (convergence as the target approached and divergence as the target receded). The likelihood of appropriate convergence and divergence increased with age, as did the ability to respond appropriately to the faster target motion. A measure of convergence lag (further decrease in interpupillary distance after target motion had ended) was obtained for trials on which the target approached the infant. Convergence lag decreased with age and was greater on trials at the faster target speed until 3 months of age. Experiment 2 measured the responses of 3, 412, and 6 month olds as a wedge prism was placed alternately in front of each eye. The prism displaced the image nasally (either 2.5° or 5°), creating inappropriate binocular eye alignment. A refixation eye movement in response to the prism was not present consistently until 6 months of age. Hypotheses as to the mechanism controlling infant binocular eye alignment are discussed with respect both to the present findings and to findings from human adults and animals.  相似文献   
940.
The study reports relationships between teachers' belief systems (Harvey), a teacher-pupil interaction measure of classroom influence, pupils' perception of the dimate of the dassroom, and pupils' academic achievement. Results demonstrate that more complex teachers encourage more pupil influence, and are perceived as having a more origin climate. In classrooms of high pupil influence and perceived origin climate, the pupils have higher academic achievement. These results are discussed in terms of the theory of personal causation and are cited as evidence for the value of the study of action sequences as related to verbal-utterances of the actors.  相似文献   
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