Psychological reactivity to discrepant events: Support for the curvilinear hypothesis

80 male and 60 female infants were observed under 5 a priori judged levels of discrepancy to assess whether sustained attention was linearly or curvilinearly related to degree of discrepancy from an experimental standard. Following habituation, $\text{7}\text{1}\text{2}$-month-old infants were exposed to either the repetition of the standard, a minimal, first- or second-level moderate discrepancy, or a novel stimulus having no relation to the standard. The related stimuli, varying in elongation, were sphere, pear, club, and cylinder-shaped objects; the novel stimulus was a different colored, tooth-like object. 80 infants observed the sphere as the standard and the cylinder as the second-level moderate discrepancy; 60 infants were exposed to the reverse order with the cylinder as the standard. The use of different stimuli at each discrepancy level controlled for specific stimulus effects. Habituation and recovery of responding were observed in an operant paradigm. Lever pressing, fixation, and vocalization increased most to the second-level moderate stimuli and decreased most to the familiar and novel objects; fretting was highest to the redundant stimuli and lowest to the moderate objects. There were no stimulus main effects or interactions. The results support the hypothesis of a curvilinear relation between stimulus discrepancy and sustained attention, excitement, and preference.     

A group approach to guilt in depressive and suicidal patients

Summary A psychiatrist and a pastoral psychologist considered the problem of guilt as a source of alienation in depressed and suicidal patients by using a four-dimensional approach in a group psychotherapy setting. This involved functioning as cotherapists representing theological and psychiatric orientations and utilizing both didactic and insight-oriented approaches to elicit and explore meaningful material related to guilt feelings. With a number of exceptions, the patients did not appear to make a sharp distinction between the cotherapists' roles. The didactic openings on guilt served to provoke ready discussion of personal conflicts involving guilt feelings, especially in the silent patients who were not easily drawn into spontaneous discussion.     

Absolute motion parallax and the specific distance tendency

In the absence of definitive cues’to distance, the perceived distance of an object will be in error in the direction of the object appearing at a distance of about 2 m from O. This tendency to perceive an object at a relatively near distance is termed the specific distance tendency (Gogel. 1969). Also, it has been found that an error in perceiving the distance of an object will result in an apparent movement of the object when the head is moved (Hay & Sawyer. 1969; Wallach, Yablick. & Smith. 1972). From these two results, it was expected that the direction of trie apparent movement of a stationary point of light resulting from head movement would vary predictably as a function of the physical distance of the point of light from O. This expectation was confirmed in an experiment in which both the perceived motion and perceived distance of the point of light were measured. The consequences of the study for the role of motion parallax in the perception of distance and for the reafference principle in the perception of object motion with head motion are discussed     

Adaptation in the constancy of visual direction tested by measuring the constancy of auditory direction

Modification of the constancy of visual direction was produced by partially adapting Ss to the displacements of the visual field caused by magnifying lenses during 1 h of continuous head turning. The adaptation effects were measured by determining the range of perceived target immobility before and after this adaptation period. A method for measuring the range of apparent immobility of an auditory signal during head movements was developed and employed to test whether a modification of the constancy of visual direction transfers to the constancy of auditory direction. No such transfer was found, and it was concluded that a modification of the constancy of visual direction does not consist in an altered evaluation of kinesthetic cues for head turning. The method and the equipment used in the investigation of the constancy of visual direction are described; knowledge of the previous brief publications on this topic is not needed.     

Interference and facilitation effects of primes upon verification processes

Priming effects on sentence verification were investigated. The semantic relation of the prime and the probe, and the interval between prime and probe presentation (SOA), were varied for both ambiguous and unambiguous sentences. Reaction time to decide that a sentence was true or false was longer if the preceding prime was a word that was unrelated to the probe than if the prime was the word “blank.” In contradiction of Posner and Snyder’s (1975) claim that conscious processes develop slowly, this result was found at SOAs as short as 250 msec. Verification performance was facilitated for both sentence types when the prime word was the first of the to-be-presented probe sentence, but the magnitude of the facilitation effects depended upon the truth value of the probe, the associative strength of the subject and predicate of the probe sentence, and upon SOA. These findings indicate that priming affects the processing of relations among concepts in semantic memory, as well as the encoding of the probe.     

Processing of visual illusions in the frequency and spatial domains

In the results we report here, complex periodic and aperiodic illusions are revealed by filtering with filters containing one or more straight edges. Positive definite filters are used both in the frequency domain and in the space domain to reveal each illusion. Rotating slit and half-plane filters are used in the frequency domain, while processing is done in the spatial domain by convolution with a rotating slit. These two schemes show similar results in revealing the illusory patterns. The implications for human visual processing are discussed.     

Identification,discrimination, and match-to-sample as instances of comparative judgment

Identification, discrimination, and match-to-sample paradigms are discussed in the context of a comparative judgment between an external stimulus and a memorial representation. An experiment comparing the paradigms at different levels of stimulus dimensionality is described. The absence of clear-cut interactions of the paradigms with dimensionality differences is offered as support for the contention that the three seemingly diverse procedures may be considered as part of a comparative judgment continuum,with performance differences reflecting increased memorial demands.     

EM algorithms for ML factor analysis

The details of EM algorithms for maximum likelihood factor analysis are presented for both the exploratory and confirmatory models. The algorithm is essentially the same for both cases and involves only simple least squares regression operations; the largest matrix inversion required is for aq ×q symmetric matrix whereq is the matrix of factors. The example that is used demonstrates that the likelihood for the factor analysis model may have multiple modes that are not simply rotations of each other; such behavior should concern users of maximum likelihood factor analysis and certainly should cast doubt on the general utility of second derivatives of the log likelihood as measures of precision of estimation.