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1.
Older adults' life satisfaction can be better understood in light of their personal goals. This study of 179 elders examined (a) how goals correlate with satisfaction, (b) whether elders maintain satisfaction by accommodating goals to past losses, and (c) how correlations between satisfaction and key predictors differ among groups with different goals. Satisfaction was related positively to social maintenance and energetic life-style goals and negatively to concerns for improvement, disengagement, stability, and reduced activity. Past losses were correlated with current goals but not with satisfaction, consistent with the notion of accommodation. A cluster analysis identified 5 patterns of goals: high demand, age prescribed, self-focused, socially engaged, and low demand. Correlations between satisfaction and other predictors differed by cluster, suggesting that the determinants of elders' satisfaction depend on personal goals.  相似文献   
2.
The relationship between endogenous-psychotic and hysterical behavior is presented in this paper on the basis of typical patients' accounts. Various patterns of behavior are revealed: chronic hysterical psychotic syndromes, acute hysterical psychotic syndromes, hysterical exalted psychotic episodes, simulated hysterical psychotic syndromes, hysterical behavior in the attempt to cope with psychosis, and pseudohysterical behavior in endogenous psychoses. The specific aspects of the doctor-patient relationship in the case of these patients are described.  相似文献   
3.
The dipeptidyl-peptidase activity of 650 liquores cerebrospinalis was obtained by means of the substrate Gly-Pro-NHNp (Gly-Pro-4-nitroanilid) at pHs of 5.5 and 7.4. In comparison with a reference collective, the suitability of the method as a supplementary liquor parameter in neurological psychiatric diagnosis was examined. The introduction of the measurement at pH 7.4 can be particularly recommended for the distinguishing of bacterial and nonbacterial meningitis.  相似文献   
4.
The investigation of enzyme activity in cerebrospinal fluid has been without relevant results for laboratories analysing spinal fluid. For neurochemical purposes, it is interesting that the Substance P is convered by Depeptidyl-aminopeptidase IV (DP IV), liberating dipeptides. The hydrolysis of nitroanilids of the form Xaa-Pro-NHNp in cerebrospinal fluid was analysed using them as peptidases substrates. Finally a method for measuring the activity was proposed.  相似文献   
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6.
Adherents of the Galton paradigm favour the concept that the simple parameter ‘speed of information processing’ has a physiological basis and determines complex achievements assessed in intelligence tests as well as social success. These assumptions are supported by inter-individual correlations. Further supporting evidence comes from total measurement where not only the information content of the stimuli is measured, but also the time to process them. This reveals an individually constant period during which 1 bit of information is processed. It is called the ‘basic period of information processing’ (BIP), which lasts 1/15 s (= 67 ms) in average adults (IQ 100) and is constant over the ranges from which target stimuli can be drawn and over varying modes of the signs (letters, numbers, musical notes, etc.). In representative samples of adults duration of BIP correlates with global IQ (r ? ?0.60): We conclude that the BIP of an adult with an IQ of 122 is 50 ms and with an IQ of 78 twice as long (100 ms). We consider BIP to be a physiological and general determinant of intelligence, being measurable at a ratio or even an absolute scale level. Thus, it appears to be suitable as a building unit for reconstructing the rather fuzzy traditional concept of general intelligence.  相似文献   
7.
Saccadic reaction times of dyslexic and age-matched normal subjects   总被引:2,自引:0,他引:2  
B Fischer  H Weber 《Perception》1990,19(6):805-818
Saccadic reaction times (SRT) were measured in a simple task: subjects had to make saccades from a central fixation point to peripheral targets, which appeared randomly 4 deg to the left or to the right. In the first test the fixation point went off before the target appeared (gap trials); in the second test it remained on the screen (overlap trials). The distribution of SRTs for trained normal adults (N = 4), untrained normal adults (N = 11), untrained normal children (aged 9-11 years, N = 9), untrained normal teenagers (aged 15-17 years, N = 8), dyslexic children (aged 9-11 years, N = 15), and dyslexic teenagers (aged 15-17 years, N = 5) were compared, with special emphasis on the number of express saccades, ie saccades with extremely short reaction times (100-120 ms, under the present conditions). In normal adults with the gap paradigm, the distribution of reaction times typically exhibits two or three modes (express saccades, fast regular saccades, and very few slow regular saccades), whereas in the overlap paradigm only one or two modes (few fast regular saccades and many slow regular saccades) are obtained. On average, normal children produce more express saccades than naive normal adults. Dyslexic children produce more express saccades than the normal age-matched controls. Among the dyslexic children, four different types of abnormalities in their reaction times were encountered. The group of dyslexic teenagers was characterized by a larger number of express saccades at the expense of fast regular saccades in gap trials and by fewer express saccades and fewer fast regular saccades in overlap trials when compared to the age-matched control group. It is concluded that the abnormal patterns of saccadic reaction times reflect defects in the system of visual attention and/or in its control over the oculomotor system, rather than indicating a defect in the oculomotor system itself. In this context, symptoms of dyslexia appear as a combination of attentional deficits and irregular timing of saccadic eye movements.  相似文献   
8.
The paper addresses three neglected questions from IRT. In section 1, the properties of the “measurement” of ability or trait parameters and item difficulty parameters in the Rasch model are discussed. It is shown that the solution to this problem is rather complex and depends both on general assumptions about properties of the item response functions and on assumptions about the available item universe. Section 2 deals with the measurement of individual change or “modifiability” based on a Rasch test. A conditional likelihood approach is presented that yields (a) an ML estimator of modifiability for given item parameters, (b) allows one to test hypotheses about change by means of a Clopper-Pearson confidence interval for the modifiability parameter, or (c) to estimate modifiability jointly with the item parameters. Uniqueness results for all three methods are also presented. In section 3, the Mantel-Haenszel method for detecting DIF is discussed under a novel perspective: What is the most general framework within which the Mantel-Haenszel method correctly detects DIF of a studied item? The answer is that this is a 2PL model where, however, all discrimination parameters are known and the studied item has the same discrimination in both populations. Since these requirements would hardly be satisfied in practical applications, the case of constant discrimination parameters, that is, the Rasch model, is the only realistic framework. A simple Pearsonx 2 test for DIF of one studied item is proposed as an alternative to the Mantel-Haenszel test; moreover, this test is generalized to the case of two items simultaneously studied for DIF.  相似文献   
9.
Two experiments are reported addressing the preparation and initiation of movements with equal or unequal timing properties for both hands. Temporal coordination was examined in two movement tasks: one in which both hands performed the movements simultaneously (simultaneous aiming task) and one in which only one alternative of two possible movements was executed (choice aiming task). For each task a different group of subjects was used. Besides the timing relationships between both movements, the effects of preparation interval (1, 3, and 5 s), the average velocity (7, 14, 17.5, and 70 cm/s), the presence of advance information about the required velocity of the movement(s), and practice were investigated. Based on the common- and the specific-timing notions, distinct hypotheses were tested as to the effects of the variables on the temporal coordination as revealed by reaction time. A main result was that the effects of timing differences between the hands was task specific. For the choice task the data are in agreement with the common-timing notion of coordination, i. e., only one timing demand at a time can be prepared, whereas in the simultaneous task evidence was obtained for the specific-timing notion, i. e., independent preparation and initiation of different timing properties for the hands. However, it is argued that the results of the choice task probably do not reflect a general inability to prepare movements of different timing requirements for both hands, but is related to a task-specific strategy of selective preparation.  相似文献   
10.
The partial credit model is considered under the assumption of a certain linear decomposition of the item × category parameters ih into basic parameters j. This model is referred to as the linear partial credit model. A conditional maximum likelihood algorithm for estimation of the j is presented, based on (a) recurrences for the combinatorial functions involved, and (b) using a quasi-Newton approach, the so-called Broyden-Fletcher-Goldfarb-Shanno (BFGS) method; (a) guarantees numerically stable results, (b) avoids the direct computation of the Hesse matrix, yet produces a sequence of certain positive definite matricesB k ,k=1, 2, ..., converging to the asymptotic variance-covariance matrix of the . The practicality of these numerical methods is demonstrated both by means of simulations and of an empirical application to the measurement of treatment effects in patients with psychosomatic disorders.The authors thank one anonymous reviewer for his constructive comments. Moreover, they thankfully acknowledge financial support by the Österreichische Nationalbank (Austrian National Bank) under Grant No. 3720.  相似文献   
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