Spatial and fixation conditions affecting the temporal course of changes in perceived relative distance

The results of two experiments are reported in which the change over time in the perceived depth location of a monocular, luminous test object with respect to two binocular luminous stimuli located at different distances was measured. It was found that: 1) The test object receded perceptually in depth over time achieving a stable location in space after 4 min of viewing. 2) The initial perceived location in depth of the test object depended upon which of the two binocular objects was fixated. When the farther binocular object was fixated the test object appeared further away than when the nearer one was fixated. 3) The size of the further binocular object also affected the initial perceived location of the test object. When it was larger, the test object appeared further away than when it was smaller. 4) There was an interaction between the binocular object fixated upon and the lateral separation between it and the test object: the smaller the separation, the greater the fixation effect.These results were accounted for in terms of the equidistance tendency, the depth adjacency principle, and a possible attentional factor. Taken together the results indicate that while reduced viewing conditions reduce the available stimulus information, they do not reduce the organizational options of the visual system.     

The factor structure of the Vocational Preference Inventory for black and white college students

This study investigated whether the variables measured by the Vocational Preference Inventory (VPI) were the same for both black and white students. Kaiser et al. (1969) have noted that the same measurements used with different populations may not measure the same variables and have presented a method of determining the degree of correspondence in the two populations. In the present study, the VPI scores for a group of black students and a group of white students were factor analyzed separately and the black structure was rotated to correspond to the white structure. The correspondence between the variables measured by the VPI for black and white students was found to be very similar. This is to say that the VPI measures the same variables for both black and white college students.     

Personality types and traits in the Vocational Preference Inventory

The relationships between the six scales on which Holland's (1973) theory is based (viz., Realistic, Investigative, Social, Conventional, Enterprising, Artistic) and the five other scales (viz., Self-control, Masculinity, Status, Infrequency, Acquiescence) of the Vocational Preference Inventory (VPI) (Holland, 1970) were investigated using canonical analysis. Considering the six personality type scales as one set of variables and the five trait scales of the VPI as the second set of variables, five significant canonical correlations were obtained for a sample of 373 mostly white undergraduate students. In a second study, three significant canonical correlations were found for a sample of 115 black college students at another school. The weights of the VPI scales suggested that three patterns of relationships among the scales are shared by the black sample and the mostly white sample.     

Stimulus encoding selectivity at high degrees of paired-associate learning

Sixty-two Ss learned six CCC trigram-digit pairs by the study-test method; 21 Ss continued the PA acquisition trials to a learning criterion of one errorless trial, while 41 Ss were carded to 300% overlearning or 24 trials, whichever came first. The Ss were then shown individual letters of the trigrams, with position cues provided, and were tested for their ability to provide the digit and produce the additional letters. Digit recall was much better to initial letters than to those in the second or third positions of the trigrams; with oveflearning, digit recall improved to the initial letters but not to letters in second and third positions. Production of additional letters of the trigrams was not appreciably related to either cue position or degree of PA learning. There was some evidence ofincreased selectivity with higher degrees of PA learning.     

Evidence for the role of post-retinal processes in simultaneous contrast

Summary Evidence is presented that the degree of simultaneous contrast produced by the bisecting line in the Koffka ring is greatly lessened by varying the perceived depth interval between this line and the Koffka figure. The retinal disparity between the line and the figure was varied to produce this effect. The slight lateral displacements of the bisecting line in the monocular images themselves necessary to produce retinal disparity with binocular viewing had no effect on the magnitude of simultaneous contrast. Interpretations based on processes operating at the retinal level such as lateral inhibition level are not supported by this finding. The results are interpreted in terms of the adjacency principle.This research was supported by National Institutes of Health Research Grant No. 00268 to the first author. Thanks are due to Donald Mershon and Walter Gogel for their helpful comments and criticisms of an earlier version of this paper.     

Childhood and adult behavior disorder: Some experimental comparisons

Seventy-six children with diagnoses of behavior disorder were tested with a motor conditional reflex test and a word association test. Essentially no differences were found when test performance was compared with that of 142 normal controls. When the diagnoses were divided into neuroses, adjustment reaction of childhood, and personality disorder, none of these subgroups showed any distinctive difference. Experimental differences between clinically excitatory and inhibitory types could not be established. The Russian reports about abnormal basic Pavlovian parameters could not be confirmed. In adult behavior disorder marked disturbances of functions are found. It is suggested that the worse prognosis in adult neurotic conditions is related to such pathophysiological factors as passive inhibition, weakness of active inhibition, inertness and complex structures with pathological excitation and inertia.     

Childhood and adult schizophrenia: Some clinical and experimental comparisons

The literature does not provide convincing evidence that childhood schizophrenia starting before age 11 represents the same disease process as adult schizophrenia, with regard to clinical symptomatology, genetic background and course of illness, and childhood schizophrenia seldom appears to involve long term schizophrenic deterioration. Our sample of 31 childhood schizophrenics studied with a battery of a motor conditional reflex tests, an autonomic conditioning test and a word association test did not present symptoms comparable to those seen in a group of adult schizophrenics tested with similar procedures. Supported by grant HDO1095 from the National Institute of Child Health and Human Development.     

The identification of structural components of an unknown language

Adult subjects attempted to identify structures (words and constituents) in sentences of a language they did not know. They heard each sentence twice-once with a pause interrupting a structural component and once with a pause separating different structural components. They were asked to choose the version that sounded more natural. An experimental group of subjects who had been previously exposed to a spoken passage in the same language as the test sentences was more successful in identifying structures of the sentences than was the control group with previous exposure to another language. This result was interpreted as demonstrating that language structure may be partially acquired during a brief exposure without reliance on meaning. It was also noted that the experimental group identified constituents more accurately than words. This result suggested that constituents, more than words, function as acquisitional units of language.