On the meaning of statistical interactions

The problems which can arise in predicting the presence or absence of statistical interactions when a theoretical model is not set into correspondence with the experimental design model are considered in the context of a specific study of developmental differences in distractibility. It is concluded that intuitive or incomplete theoretical analyses often lead to incorrect prediction concerning statistical interactions and to spurious or ambiguous conclusions based on the confirmation or disconfirmation of those predictions and that the analysis of the relationship between a theoretical model and the experimental design model will offer considerable protection against such undesirable outcomes.     

Stochastic PERT networks as models of cognition: Derivation of the mean,variance, and distribution of reaction time using Order-of-Processing (OP) diagrams

It is frequently assumed that the mental activity which leads to a given response is made up of separable components or processes. One or more of the processes are assumed to contribute to the time required to respond. Computation of the mean, variance, and distribution of the reaction time is relatively straightforward when all processes are arranged in series or parallel. However, such is not the case when the processes have complex arrangements. A solution to a useful special case of the above problem is proposed. Specifically, it is shown that simple computations yield closed form expressions for the mean, variance, and distribution of reaction time when the processes can be arranged in a stochastic PERT network and when the durations of individual processes are sums of mutually independent, exponentially distributed random variables. The method of solution relies on the construction of an Order-of-Processing (OP) diagram from the original PERT network representation of behavior.     

Mental capacity,mental effort,and cognitive style

This study tests the relationship between two theoretical models of human attentional capacity: Pascual-Leone's mental capacity and Kahneman's mental effort. It was found that significant and positive correlations exist between the empirical measures of the above constructs, and the relationship is demonstrated via construct validation by showing that the two constructs relate in the same manner to the subject's cognitive style (i.e., field-dependence/independence).     

The efficacy of progressive relaxation in systematic desensitization and a proposal for an alternative competitive response--the relaxation response.

The theoretical basis of systematic desensitization is reciprocal inhibition in which an alternative, competitive response to anxiety is conditioned to arousal-producing, phobic stimuli. Abbreviated training in progressive relaxation is believed to serve as a competitive response to anxiety by decreasing autonomic nervous system activity. However, physiologic studies of progressive relaxation have not substantiated that its practice is associated with such decreased autonomic activity. Consequently, the use of progressive relaxation has been a confounding factor in the determination of the function of reciprocal inhibition in systematic desensitization. To confirm and refine the theoretical constructs of reciprocal inhibition, it is necessary to test the effects of a response which is competitive to the anxiety response. Such a response may be the relaxation response which is characterized by physiologic changes consistent with decreased autonomic nervous system activity. Derived from meditational practices, techniques which ehcit the relaxation response incorporate the element of focused attention which has been implicated as a critical factor in systematic desensitization. Thus, the use of the relaxation response should be a more appropriate method than progressive relaxation if the therapeutic usefulness of systematic desensitization is indeed due to reciprocal inhibition.     

Prosopagnosia and visual object agnosia: A behavioral study

A left-handed woman developed visual object agnosia, prosopagnosia, and visual disorientation after resection of the right occipital lobe. Color agnosia and alexia were absent. When asked to identify objects presented visually, the patient's errors represented visually related objects (underspecifications) or perseverations. Identification was facilitated when she observed the object being used in a natural way. Identification was impaired by surrounding the object with unrelated objects, decreasing the background illumination, decreasing the duration of exposure of the object to the patient, and probably also by decreasing the visual angle subtended by the object. In addition, there were disturbances of visualization (i.e., imaging in the absence of a visual stimulus) that paralleled the perceptual difficulties. We conclude that: (1) A deficit in visual perception, characterized by insufficient feature analysis of visual stimuli, was the basis of the visual agnosia in this case. (2) The visual agnosia could not be explained by (a) a vision-language disconnection syndrome, (b) decay of visual memory traces, or (c) deficiencies in the visual fields (pathologic Funktionswandel). (3) The ability to visualize (visual imagery) probably utilizes some of the same neural pathways used in perception. (4) The results in this case probably can be generalized to some but not all cases of visual agnosia; in particular, the deficit in most previously reported patients with prosopagnosia is similar to that of our case. However, agnosic alexia and color agnosia usually have a different neuropsychological basis.     

Basic level and superordinate level categorization by autistic, mentally retarded, and normal children

Three experiments designed to test autistic children's nonverbal and verbal categorization abilities are reported in this paper. In the first two experiments, 14 autistic children were compared to 14 retarded and 14 normal children matched on verbal mental age. Their ability to categorize pictures from basic level categories and from biological and artifactual superordinate level categories was assessed using a matching-to-sample procedure. The three groups of subjects were similar in their performance. Basic level categorization was easier than more abstract categorization, and for all three groups, prototypicality played a role in categorizing superordinate level concepts; that is, children in all three groups made more errors categorizing peripheral examples. In the third experiment, a subgroup of 7 autistic children showed evidence that their lexicons were well organized and that they appreciated the meaning relationships among words at the superordinate level. These findings suggest that autistic children do not suffer a specific cognitive deficit in the ability to categorize and form abstract concepts, as has been previously suggested in the literature.     

A scale for the measurement of role-playing ability

A convenient paper-and-pencil measure of acting or role-playing ability was constructed, validated, and compared to a variety of theoretically and methodologically similar and dissimilar scales, including a specially designed improvisational situations test. Results indicate that the new scale provides both a reliable and valid screening device for the study of role-playing ability.     

Effect of preacquisition UCS exposure on classical conditioning of the rabbit's nictitating membrane response

Conditioning of the rabbit nictitating membrane response was found to be inversely related to the number (0, 50, 200, 350) and intensity, (0, 1, 3, 5 mA) of preacquisition UCS exposures and directly related to the interval between preexposure and acquisition (0 or 24 hr). The results were discussed in terms of sensory adaptation, habituation, blocking, and emotional reactivity.     

A test of causal sequences in two models for development of career-orientation in women

To evaluate the tenability of two causal orderings of variables in the development of career-orientation, responses of 92 college senior women to Need Achievement, Dating Frequency, and Career-Orientation items were analyzed. The postulated orderings were derived from two models: a compensatory model implying that failure in a woman's heterosexual affiliation leads to high nAch which, in turn, produces high C-O; an enrichment model suggesting that a woman's high nAch may lead to high C-O which, in turn, decreases heterosexual affiliation. Criteria for temporal sequences as per the Simon-Blalock correlational procedures rendered the enrichment model more tenable.     

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.