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921.
Integration psychophysics was used to explore the taste perception of mixtures of sucrose, fructose, and citric acid. Three levels of each stimulus were varied in a 3 x 3 x 3 factorial design. Subjects rated total intensity, sweetness, and acidity of the 27 mixtures on graphic rating scales. Consistent with earlier work, the perceived total intensity of the tertiary mixtures was found to be dictated by the intensity of the (subjectively) stronger component alone (i.e., either the integrated sweetness or the acidity, whichever was the more intense). In contrast, the sweetness and acidity of the mixture were susceptible to mutual suppression: Sweetness suppressed acidity, acidity suppressed sweetness. There was, however, a difference between sucrose and fructose in their interactions with citric acid, fructose being the more susceptible to suppression. This selectivity of suppression indicates that the two sweetnesses could not have been inextricably integrated. Implications for taste coding are discussed, and the findings are reconciled in terms of two separate coding mechanisms: one for taste intensity, another for taste quality.  相似文献   
922.
Induced motion (IM) of a fixated spot stimulus and shifts of the apparent straight-ahead (ASA) from the objective median plane were studied as a function of the velocity of a full-field optokinetic background stimulus. Both IM and ASA were influenced similarly by changes in stimulus velocity. The magnitude of both responses, averaged across subjects, increased to a peak level with background velocities of 40-80 deg/sec and decreased at higher velocities. Individual subjects differed with respect to the precise functions by which IM and ASA shifts were related to stimulus velocity. However, for individual subjects, the effects of velocity on IM and ASA shifts were typically highly correlated. Although IM is correlated with shifts of ASA in the opposite direction, the magnitude of the ASA shift is insufficient to account for the observed IM.  相似文献   
923.
The concurrent validity of the motor domain from the Vineland Adaptive Behavior Scales was estimated using scores from the Peabody Developmental Motor Scales as criteria. A moderately high correlation between the measures was obtained. Implications, particularly for preschool children, were discussed.  相似文献   
924.
The Test of Nonverbal Intelligence (TONI) and Wechsler Intelligence Scale for Children--Revised (WISC--R) were administered to 46 Native American and white students who were suspected by their classroom teachers of having learning handicaps. Pearson correlations between these sets of IQs ranged from .42 (TONI and WISC--R Performance) to .89 (WISC--R Verbal and Full Scale).  相似文献   
925.
A major goal of the Army Selection and Classification Project was to develop an experimental predictor battery that would best supplement the Armed Forces Vocational Aptitude Battery for making selection and classification decisions for entry-level enlisted personnel. That is, what predictor measures would best serve the needs of all the jobs in an entire selection/classification system? This paper describes the characteristics of the new test battery and the procedures that were used to develop it. The major steps in the procedure were a structured literature search using a standard protocol, an extensive expert judgment study of expected true validities for a population of predictor variables against a population of performance components, fabrication of modularized software and a special response pedestal for computerized measurement of perceptual and psychomotor abilities, evaluations of experimental measures in three iterative pilot tests and one major field test, and a series of reviews by a panel of scientific advisers. The test battery that resulted from this 2 1/2-year development effort is described. The basic psychometric properties of each measure, as determined in a large concurrent validation sample, are also described.  相似文献   
926.
MODELING JOB PERFORMANCE IN A POPULATION OF JOBS   总被引:9,自引:0,他引:9  
The Army Selection and Classification Project has produced a comprehensive examination of job performance in 19 entry-level Army jobs (Military Occupational Specialties) sampled from the existing population of entry-level positions. Multiple methods of job analysis and criterion measurement were utilized in a subsample of nine jobs to generate over 200 performance indicators, which were then used to assess performance in a combined sample of 9,430 job incumbents. An iterative procedure involving a series of content analyses and principal components analyses was used to develop a basic array of up to 32 criterion scores for each job. This basic set of scores formed the starting point of an attempt to model the latent structure of performance in this population of jobs. After alternative models were proposed for the latent structure, the models were submitted to a goodness-of-fit test via LIS-REL VI. After accounting for two components of method variance, a five-factor solution was judged as the best fit. The implications of the results and the modeling procedure for future personnel research are discussed.  相似文献   
927.
Conclusions To conclude then, our question was, What determines the content of a thought? This question gets its punch by being set against the background assumption that thoughts are internal physical occurrences. The answer I have proposed is that thoughts can be classified in four importantly different ways. Introspection yields syntactic categories. These are important for cognitive processing, but they do not correspond to contents. A second way of categorizing thoughts is in terms of narrow content. This is determined by the functional role of the thought in rational architecture together with the way in which that rational architecture is tied to the world through input correlations. Narrow contents are indexical, so to get truth bearers we must augment the narrow contents with the values of the indexical parameters. Propositional content can be taken to consist of pairs of narrow contents and values for indexical parameters. Finally, thoughts can be classified in terms of that clauses. This kind of classification does not uniquely determine propositional content, but describes it in a more general way.  相似文献   
928.
Several investigations have indicated that length of residence can predict acculturation associated with stress. However, there have been no studies from a psychophysiological perspective to assess whether length of residence affects physiological reactivity. The purpose of this study was to compare reactivity to psychological stress in female Japanese students of long- and short-term residence at a large university in northeastern USA, after administering a stress questionnaire to examine stress in adjusting to their US academic lives. 12 subjects were randomly chosen for each group (short- and long-term residence) from an initial population of 90 students. The subjects were presented three stressors (English-reading, stress-imagination, and arithmetic) for 2 min. each, with a 6-min. recovery period following each stressor. A significant interaction appeared for groups over time on heart-rate reactivity. While the long-term group had a linear component in heart rate across time for the tasks, the short-term group did not. Although the short-term group had higher skin temperature than the long-term group, only the short-term group had a tendency to increase skin temperature after the tasks. These data suggest that continued study of physiological reactivity to stress may be useful for developing techniques for coping with acculturative stress.  相似文献   
929.
A group of 107 children with vascular diseases of the nervous system aged 3-14 years have been studied. In 100 children of the study group acute disturbances of the brain blood circulation have been found, out of which 37 children were with transitory ischemic attacks; 29 were found to be with brain ischaemia; 22-with haemorrhages (7 cases with subarchnoidal, 9 cases with intracerebral and 6 cases with subarachnoidal-parenchimatose); 5 children had wenous thromboses; 7 children were with spinal strokes. In other 7 children we found the presence of Sturge-Weber syndrome. Congenital vascular malformations have been found in 32 children (30%), out of which 16 children (15%) with loops and stenosis of the extracranial segments of the internal carotid artery, and another 16 children (15%) with AV-malformations. Congenital and acquired heart diseases are found to be primary cause for the strokes in 12 children (11%). Considerable is the rate of the epileptic seizures in the acute stage of the strokes as well as of the residual epileptic syndromes.  相似文献   
930.
L Eitinger 《Psyche》1990,44(2):118-132
The author reports on a Norwegian investigation extending over more than 30 years, which showed that, apart from a few exceptions, all former concentration camp inmates and prisoners in Nazi jails manifest permanent physical and psychic damage. On the basis of these findings the Norwegian government has established a generous statutory compensation program. Unlike its counterpart in the Federal Republic of Germany, this program does not require applicants to demonstrate the cause of illness or its consequences in each case. The method of the investigation is presented in detail.  相似文献   
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