The effects of instructional set on physiological response to stressful imagery

Centrally mediated or cognitive variables have received considerable attention in clinical research. With the establishment of the effectiveness of such specific treatment techniques as systematic desensitization (Paul. 1969a. 1969b). a question arises as to the influence of cognitions on process and outcome variables in such learning based treatments (Lang. 1971). Research investigating the influence of demand characteristics and subject expectancies has demonstrated such centrally mediated variables can significantly influence overt, behavioral and self-report measures of fear, stress, or anxiety (cf. Borkovec. 1972: Marcia. Rubin and Efran. 1969; McGlynn. Maelia and Nawas. 1969: McGlynn. Reynolds and Linder. 1971: Oliveau. Agras. Leitenberg and Wright. 1969; Rappaport. 1972: Rosen. 1974).However. Borkovec (1972) and Rappaport (1972) failed to obtain expectancy effects on physiological measures of anxiety. Neither investigation provided for an independent assessment of subjects' actual expectancies, or belief in the instructions, as recommended by Davison and Wilson (1973). Borkovec administered clinical procedures over four sessions and varied the information communicated about the ‘purpose’ of the treatments (physiological versus therapeutic instructions). Differential rationales for differential expectancies of physiological reactivity were not provided. After each session, subjects reviewed the same false physiological records depicting reductions in fear responses. Although these changes were explained either physiologically or therapeutically. the fact that such reductions were emphasized should have attenuated differences between groups. Rappaport (1972) exposed subjects to a fearful stimulus and varied the suggestion and rationale for the pseudotreatment: no expectancy (stress research): therapeutic expectancy (fear reduction); and negative expectancy (fear increase). The lack of an independent assessment of the expectancy manipulation, as well as the exclusion of a specific therapeutic procedure, make it impossible to interpret the results in relation to expectancy effects on physiological fear responses during the administration of therapeutic procedures. There is other evidence, however, that suggestion and instructional set can significantly influence somatic and autonomic response systems (Barber. 1961. 1965; Sternbach. 1964. 1965).The primary purpose of this study was to evaluate the effects of instructional set on physiological responses to stressful imagery. This was an early step in a research program investigating the effects of instructional and informational variables on physiological responses of clinical interest. One half of the subjects received abbreviated live relaxation training (R) as described m a manual by Bernstein and Borkovec (1972) and based upon the original work of Jacobson (1938). The other half received an inert placebo pill and undertook a target detection task (P). The latter procedure was similar to that used by Paul (1966). Although both procedures had previously been shown to have relaxing effects, the P task was included as an additional control for any potential effects specific to the tension-release procedure of R. In order to evaluate the effects of instructional set, one half of each of the above two groups received instructions designed to lead to an expectancy of response inhibition to stressful imagery by the respective procedure (Decrease Stress Response. DSR). while the other half received instructions designed to lead to an expectancy of an increased response to stressful imagery by the respective procedure (Increase Stress Response. ISR). Each subject visualized three individually specified items that were the most frightening scenes imaginable prior to training and four times after training visualized the scene producing the largest response. Considerable effort was devoted to eliciting from each subject the most frightening items possible for her. and it was clear from subject comments that the items did elicit negative emotional responses.Since previous research (Barber. 1961. 1965; Sternbach. 1964. 1965) indicated that instructional set can influence physiological reactivity, it was hypothesized the DSR) subjects should exhibit a greater reduction in emotional response from pre- to posttraining than ISR subjects.     

Semantic memory verification of binary statements by children at three academic levels

Ninety-six binary statements were administered to 120 children randomly selected from three academic levels. The children were to respond TRUE or FALSE to each statement. Error count and latency for correct responses were used as measures of performance. The Constituent Comparison Model (Carpenter, P., & Just, M. A., Psychological Review, 1975, 82, 45–73), which postulates that verification latency will increase linearly with a linear increase in the number of hypothesized constituent comparisons, accounts quite well for the results obtained in this study. Furthermore, the results suggest an increasing efficiency in semantic memory verification across the three academic levels as reflected by a decrease in variability of performance, a decrease in the time required to read and encode sentences, and a decrease in the time required per constituent comparison.     

Shape constancy and a perceptual bias towards symmetry

In attempting to judge whether a briefly presented rotated figure was symmetrical (circle or square) or asymmetrical (ellipse or rectangle), a bias towards perceiving symmetry was evident. This bias appears to be perceptual rather than judgmental in origin in that it was affected neither by variations in the probability of occurrence of symmetrical figures nor by familiarization with the stimuli. A characterization of the stimulus similarity space based on the shape-slant invariance hypothesis is presented, and a model which incorporates both the similarity space and the symmetry bias is proposed. The model can account for our paradoxical finding that the more asymmetrical some projected images, the more likely they will be perceived as symmetrical. This model can also account for Massaro’s (1973, 1975) results on shape constancy. However, Massaro’s theory was not supported in that extension in depth did not account for increased difficulty of shape judgments.     

A note on the use of mood's likelihood ratio test for item analyses involving 2 × 2 tables with small samples

Mood's likelihood ratio test is generally considered an unreliablex ² approximation in 2 × 2 contingency tables containing expected cell frequencies less than five. Probability values were computed for 60 such tables as part of an item analysis for two 30-item alternate forms of a measure. The rank orders of the items, from best to worst differentiators, as determined separately by Mood's test and by Fisher's exact test correlated .97 for one form and .96 for the other.     

A coefficient of imbalance for content analysis

This article presents a Coefficient of Imbalance applicable to any type of communication that may be classified into favorable content, unfavorable content, neutral content, and non-relevant content. The combined influence of the average presentation of relevant content and the average presentation of total content is reduced to two components, the coefficients of favorable imbalance and of unfavorable imbalance. A precise definition of imbalance is developed and measured against ten criteria.The authors wish to express their appreciation to Mr. Harold Elsten, Dr. Natan C. Leites, and Mr. Ithiel Pool for valuable suggestions and criticisms.