Role of intertrial interval following an escape or avoidance response in bar-press avoidance

In three experiments, rats learned bar-press avoidance as a function of the intertrial interval following an escape or an avoidance. The general hypothesis is that the length of these intervals affects bar-press avoidance differentially, depending on whether an avoidance follows an escape (avoidance/escape) or an avoidance (avoidance/avoidance) on the previous trial. Specifically, it is proposed that short escape ITIs will facilitate avoidance/escape and avoidance/avoidance, while avoidance ITIs will have no effect on avoidance responding. The results tend to support this hypothesis. The shorter the intertrial interval following an escape, the higher the probability of both measures: avoidance/escape and avoidance/avoidance. No effect of avoidance interval was found on avoidance/avoidance. Unpredictedly, however, it was found that in comparison to a very short intertrial interval following an avoidance (0.5 sec), relatively long intervals (5 and 45 sec) facilitate avoidance/escape. These results were interpreted as mainly reflecting nonassociative factors such as shock-produced activity.     

Engaging “Resistant” Families in Treatment

Many families, when presented with the option of family therapy, are less than eager to participate. This paper comprises the second and third parts of a series on engaging “resistant” families. ¹ 1 The first paper in this series, authored by J. M. Van Deusen, M. D. Stanton, S. M. Scott, and T. C. Todd, is entitled “Engaging “Resistant” Families in Treatment: I. Getting the Drug Addict to Recruit His Family Members” and appeared in the International Journal of the Addictions 15 (7): 1069–1089, 1980. A revised and expanded version of Part II is presented in M.D. Stanton, T. C. Todd, and Associates, The Family Therapy of Drug Abuse and Addictions New York, Guilford, in press.
Part II presents 21 principles and a number of techniques and strategies that have been developed for successfuly recruiting such families. These techniques should be applicable for engaging resistant families with all types of presenting problems. Part III provides an analysis of the important variables involved, along with data on cost efficiency and administrative costs. It was found that when therapists had administrative control of their cases, serving in dual roles as both therapists and drug counselors, the recruitment effort was (a) more effective (i.e., complete families, including both parents or parent surrogates, were recruited in 77 per cent of the cases), and (b) twice as cost efficient. Two-thirds of the non-engaged families were not recruited because the index patient would not allow family members to be contacted. Black families were more difficult to recruit than whites. Data on cost efficiency and on the actual administrative costs of recruiting families are also provided. We conclude that the engagement process requires a revision in therapeutic philosophy, since such families are often desperately in need of help but are unavailable unless therapists make a special effort to reach them.     

Self-Efficacy,Perceptions of Success,and Intrinsic Motivation for Exercise1

A number of investigators have attempted to identify the determinants of continued participation in exercise regimens. Within a social cognitive framework, the present study examined the relationships among self-efficacy cognitions, perceptions of success, and multidimensional intrinsic motivation in the exercise domain. Multivariate analyses of variance indicated that highly efficacious individuals were more intrinsically motivated toward aerobic dance than were their less efficacious counterparts. However, multiple regression analyses revealed both perceptions of success and self-efficacy to account for significant variance in intrinsic motivation at both the composite and dimensional levels. Moreover, perceptions of success were considerably stronger predictors than were efficacy cognitions. The results are discussed in terms of the need for multiple measures of perceived success, the employment of longitudinal designs to determine the direction of causality among these variables, and possible implications for adherence issues.     

Co-operative solutions to the Prisoner's Dilemma

For helpful comments, my thanks to Robert Bright, Richmond Campbell, Julia Colterjohn, Peter Danielson, Ish Haji, Keith Lehrer, Robert Martin, Victoria McGeer, Terrence Tomkow and an anonymous referee. I also thank the Canadian S.S.H.R.C. for a Doctoral Fellowship and Dalhousie University for a Killam Post-Doctoral Fellowship.     

Violence and degradation as themes in "adult" videos

Videocassettes have become the dominant medium for pornography. One previous content analysis examined the prevalence of violence in such videos. The Attorney General's Commission on Pornography (1986) has asserted that nonviolent pornography depicting degradation produces harm similar to that from violent pornography. Content analysis of a 10% random sample (n = 50) of the videos displayed in the "adult" section of a video store showed that 13.6% of the scenes in the videos contained violent acts and 18.2% contained degrading acts.     

Categories and particulars: prototype effects in estimating spatial location

A model of category effects on reports from memory is presented. The model holds that stimuli are represented at 2 levels of detail: a fine-grain value and a category. When memory is inexact but people must report an exact value, they use estimation processes that combine the remembered stimulus value with category information. The proposed estimation processes include truncation at category boundaries and weighting with a central (prototypic) category value. These processes introduce bias in reporting even when memory is unbiased, but nevertheless may improve overall accuracy (by decreasing the variability of reports). Four experiments are presented in which people report the location of a dot in a circle. Subjects spontaneously impose horizontal and vertical boundaries that divide the circle into quadrants. They misplace dots toward a central (prototypic) location in each quadrant, as predicted by the model. The proposed model has broad implications; notably, it has the potential to explain biases of the sort described in psychophysics (contraction bias and the bias captured by Weber's law) as well as symmetries in similarity judgments, without positing distorted representations of physical scales.     

Analysis of the elements of attention: A neuropsychological approach

A model for conceptualizing the components or elements of attention is presented. The model substitutes for the diffuse and global concept of attention a group of four processes and links them to a putative system of cerebral structures. Data in support of the model are presented; they are derived from neuropsychological test scores obtained from two samples, the first consisting of 203 adult neuropsychiatric patients and normal control subjects, and the second, an epidemiologically-based sample of 435 elementary school children. Principal components analyses of test scores from these two populations yielded similar results: a set of independent elements of attention that are assayed by different tests. This work presents a heuristic for clinical research in which the measurement of attention is essential.     

If the boy loves the girl and the girl loves the dog,does the boy love the dog?: The overgeneralization of verbal transitive inference skills

Two studies investigated 4- to 10-year-old children's capacity to make verbal transitive inferences. The results of the two studies suggest that the development of transitive inference skills follows a specific to general developmental path, and that children overgeneralize their verbal transitive inference skills to inappropriate relational terms prior to determining the general principle that underlies the use of relational terms in transitive sentences.