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981.
Analyzed explanatory style across the life span. 30 Ss whose average age was 72 responded to questions about their current life and provided diaries or letters written in their youth, an average of 52 years earlier. A blind content analysis of explanatory style derived from these 2 sources revealed that explanatory style for negative events was stable throughout adult life (r = .54, p less than .002). In contrast, there appeared to be no stability of explanatory style for positive events between the same 2 time periods. These results suggest that explanatory style for negative events may persist across the life span and may constitute an enduring risk factor for depression, low achievement, and physical illness.  相似文献   
982.
983.
Previous psychophysiological research has demonstrated that both anger expression and anger suppression are related to cardiovascular responses, but in an inconsistent fashion. The present study tested the following hypotheses: (a) that the influence of anger expression style on psychophysiological responses would be limited to Ss exposed to an anger instigation, and (b) that the specific pattern of psychophysiological responses would vary as a function of whether Ss were induced to use their preferred vs. nonpreferred mode of anger expression style in response to the instigation. Seventy-eight male college undergraduates were randomly assigned to work on a task with either an annoying or a pleasant confederate and subsequently to write either a negative or a positive evaluation of the confederate. Blood pressure was measured intermittently and heart rate continuously throughout task performance and a subsequent 15-min rest period. Ss' preferred method of anger expression had been previously assessed by a self-report questionnaire. Systolic blood pressure results generally were consistent with the hypotheses. Implications of the findings for the etiology of cardiovascular diseases are discussed.  相似文献   
984.
We investigated the sensitivity of the Bender (1938) Visual-Motor Gestalt Test (BGT) using the Halstead-Reitan Neuropsychological Battery (HRB) as the criterion for cortical dysfunction. We studied 95 subjects over age 55 who had been diagnosed as having dementia or pseudodementia. Subjects were classified as mild, moderately, or severely impaired on the HRB and as impaired or unimpaired on the BGT. The results indicated that the BGT is less sensitive (36%) than was expected when used on an impaired geriatric population. The data further indicated that false negatives occurred more frequently with the BGT when individuals had mild neuropsychological impairment. Less frequent misclassifications occurred as the severity of impairment on HRB indices increased.  相似文献   
985.
Delusions and hallucinations reported in the social histories of 150 patients admitted to an East Texas state hospital during the 1930s and of 150 patients admitted during the 1980s were examined for content that would characterize and contrast the patient subcultural milieu of the two time periods. Patients admitted during the 1930s tended to reflect the material deprivation and personal powerlessness of the great depression in delusions of great wealth and positive "special powers." The hallucinatory visions and voices of the 1980s patients reflected a more threatening and negative subcultural milieu, with more visions of blood, snakes, and dead people or animals. Command hallucinations to hurt, to kill, or to do "perverse things" would also suggest that the subculture milieu of the 1980s had become more dangerous.  相似文献   
986.
Little research has been conducted on Loevinger's Washington University Sentence Completion Test of Ego Development in adult psychiatric outpatients. The measure is a promising method of assessing a construct of personality and character functioning that should be useful in research on psychopathology and in choosing treatment modalities. The data presented in this study address the question of the psychometric adequacy of the measure in this segment of the subject population. Specifically, estimates of interrater reliability, internal consistency, and test-retest reliability are presented for a sample of 42 adult outpatients. In addition, the relationship between total protocol ratings and item sum scores is explored.  相似文献   
987.
Six pigeons were trained with a chain variable-interval variable-interval schedule on the left key and with reinforcers available on the right key on a single variable-interval schedule arranged concurrently with both links of the chain. All three schedules were separately and systematically varied over a wide range of mean intervals. During these manipulations, the obtained reinforcer rates on constant arranged schedules also frequently changed systematically. Increasing reinforcer rates in Link 2 of the chain increased response rates in both links and decreased response rates in the variable-interval schedule concurrently available with Link 2. Increasing Link-1 reinforcer rates increased Link-1 response rates and decreased Link-2 response rates. Increasing reinforcer rates on the right-key schedule decreased response rates in Link 1 of the chain but did not affect the rate in Link 2. The results extend and amplify previous analyses of chain-schedule performance and help define the effects that a quantitative model must describe. However, the complexity of the results, and the fact that constant arranged reinforcer schedules did not necessarily lead to constant obtained reinforcer rates, precluded a quantitative analysis.  相似文献   
988.
Effects of relative reinforcer frequency on complex color detection   总被引:1,自引:1,他引:0  
Pigeons were trained under a discrete-trials detection procedure in which one of a set of color stimuli was presented on the center key and a single response turned off the stimulus and illuminated two side keys. Single responses to one or the other side key produced occasional reinforcers depending on the value of the color stimulus. In Experiment 1, one color-stimulus set comprised 559, 564, 569, and 574 nm, and right-key pecks were occasionally reinforced following presentations of members of this set. The other stimulus set comprised 579, 584, 589, and 594 nm, and left-key pecks were occasionally reinforced following presentations of members of this set. Across seven experimental conditions, the left/(left + right) relative reinforcer frequency was varied from .1 to .9. In Experiment 2, one stimulus set contained only one member, 574 nm, and right-key responses were occasionally reinforced following its presentation. Over 12 experimental conditions, two manipulations were carried out. First, the number of stimuli comprising the other stimulus set was increased from one (579 nm) to two (579 and 584 nm) to three (579, 584, and 589 nm) and to four (579, 584, 589, and 594 nm), and left-key responses were reinforced occasionally following center-key presentations of members of this set. Second, for each stimulus combination, the left/(left + right) relative reinforcer frequency was varied from .1 to .5 to .9 across three experimental conditions. The principal finding of Experiments 1 and 2 was that reinforcers and stimuli interacted in their effects on behavior. In Experiment 3, pairs of adjacent stimuli (5 nm apart) in the range 559 to 594 nm were presented in each experimental condition, and the left/(left + right) relative reinforcer frequency was held constant at .5. The data from all three experiments were analyzed according to a detection model describing performance in multiple-stimulus two-response procedures. This model provided independent measures of stimulus discriminability, contingency discriminability, and bias. The analysis showed that (a) consistent with the color-naming function, pigeons were better able to discriminate between higher nanometer values than lower nanometer values; (b) their ability to discriminate between the stimuli was independent of the number of wavelengths comprising each stimulus set; (c) they allocated delivered reinforcers very accurately to the previously emitted response; and (d) no consistent biases emerged.  相似文献   
989.
In two experiments, rats were trained to deposit ball bearings down a hole in the floor, using an algorithmic version of shaping. The experimenter coded responses expected to be precursors of the target response, ball bearing deposit; a computer program reinforced these responses, or not, according to an algorithm that mimicked the processes thought to occur in conventional shaping. In the first experiment, 8 of 10 rats were successfully shaped; in the second, 5 of 5 were successfully shaped, and the median number of sessions required was the same as for a control group trained using conventional shaping. In both experiments, “misbehavior,” that is, excessive handling and chewing of the ball bearings, was observed, and when the algorithmic shaping procedure was used, misbehavior could be shown to occur in spite of reduced reinforcement for the responses involved.  相似文献   
990.
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