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971.
In a study of recognition memory for pictures, we observed an asymmetry in classifying test items as "same" versus "different" in left-right orientation: Identical copies of previously viewed items were classified more accurately than left-right reversals of those items. Response bias could not explain this asymmetry, and, moreover, correct "same" and "different" classifications were independently manipulable: Whereas repetition of input pictures (one vs. two presentations) affected primarily correct "same" classifications, retention interval (3 hr vs. 1 week) affected primarily correct "different" classifications. In addition, repetition but not retention interval affected judgments that previously seen pictures (both identical and reversed) were "old". These and additional findings supported a dual-process hypothesis that links "same" classifications to high familiarity, and "different" classifications to conscious sampling of images of previously viewed pictures.  相似文献   
972.
DeFries and Fulker (1985) employed a multiple regression analysis of twin data in which a cotwin's score is predicted from the proband's score, the coefficient of relationship (R = 1.0 for monozygotic twins and 0.5 for dizygotic twins), and their interaction to yield direct estimates of heritability (h2) and the proportion of variance due to common or shared environmental influences (c2). The purpose of the report is to extend this model to allow for the analysis of data from more than two familial relationships simultaneously. Data from identical twins, fraternal twins, and siblings pairs, in which one member of each pair was selected based on low reading performance, were analyzed. To analyze the data simultaneously, additional coefficients were added to the regression equation in order to differentiate shared environmental influences of twins and siblings. When the model was applied to the combined cognitive data, significant estimates for heritability were obtained in three of the six tests analyzed. The results also indicated a lack of justification for the separate twin and sibling environmental parameters, and a discussion of more parsimonious models is included.  相似文献   
973.
974.
Previous experimental investigation of the effects of repeating an unfamiliar stimulus suggests that mere exposure breeds attraction (e.g., Zajonc, 1968). On the other hand, correlational work with naturally occurring stimuli such as names, music, or landscapes suggests that there is also an overexposure effect: the preference function does rise with familiarity at first but then reaches a turning point and diminishes. The study (N=72) demonstrates this inverted-U relationship in an experimental setting. The stimuli were synthetic nonsense speech, permitting exact control of exposure durations and interstimulus intervals. The critical factors for demonstrating the effect are probably (1) the inclusion of a large number of repetitions, and (2) blocked repetition of each stimulus in a homogeneous sequence not interspersed with other more or less frequent stimuli.  相似文献   
975.
976.
A social skills training program was evaluated with emotionally disturbed adolescent inpatients. The targeted social skills required an action or reaction within six skill areas. The program was adapted from a commercially available social skills training game that features the use of response specific feedback, self-monitoring, individualized reinforcers, and individualized performance criteria. A peer conducted the baseline and posttraining sessions while the training was conducted by an adult who had no previous interactive history with the subjects. A multiple baseline design across groups demonstrated that the program increased appropriate responding in all skill areas and that these effects generalized during the posttraining peer conducted sessions. A generalization test indicated that the subjects used their newly learned skills with a novel adult outside the training setting. The program appears quite applicable to emotionally disturbed adolescents since it targets skills in a variety of areas and employs standardized procedures to enhance replicability.  相似文献   
977.
Chronic pain consisting of anesthesia dolorosa secondary to bilateral interruption of the trigeminal nerves is presented as a brain stem reticular denervation syndrome. Electrothalamograms revealed fast frequency discharges in the mesothalamic prerubral and centermedian reticular formation. Mesothalamic electrical stimulation attenuated the discharges. Pain and other symptoms presumably of brainstem origin also were attenuated or abolished by therapeutic electrical stimulation twice daily. It is postulated that brain stem-represented behavioral generators are implicated by the reticular discharges in order to produce the complex symptomatology. Consequently the symptom complex is collectively identified as a brainstem “mini-discharge” syndrome. A theoretical discussion is presented to defend the thesis that reticular denervation-induced low threshold discharge system accounts for the episodic states of pain, dyskinesia, mood, and memory disturbances.  相似文献   
978.
979.
A questionnaire monitoring occupational aspiration, ethnic identification, adolescent experience, and self-esteem was administered to a large sample of Indian and Anglo-Saxon British male and female adolescents attending school in the West Midlands. The relationship between these variables and differences between the four groups were consistent with predictions derived from the social identity approach to intergroup relations and group behaviour (Tajfel & Turner, 1979). Indian males were found to possess a social mobility belief structure that mediates high occupational aspirations and keeness to marry out of their ethnic group. In contrast, Indian females were found to possess a social change belief structure associated with acceptance of the status quo and lower aspirations. Males and Anglo-Saxons reported higher self-esteem than females or Indians. The adolescent experience findings were less clear, but were consistent with the general interpretation of the data that the differences in intersex relations and gender-related experiences are contingent on ethnicity.  相似文献   
980.
A technique is described in which line-drawn pictures can be rapidly interlaced, allowing for sequential part presentation or tachistoscopic presentation on the Apple II. This is accomplished using a two-stage process in which the pictorial stimuli are converted into machine code data files and then used to create a rapidly changing display consisting of two or more line drawings. The latter stage could be accomplished in less than 2 msec but is limited by the frame time of the monitor (17–20 msec).  相似文献   
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