Do Cognitive Behaviour Therapies Validate Cognitive Models of Mood Disorders? A Review of the Empirical Evidence

The efficacy of Cognitive Behaviour Therapy (CBT) in the treatment of depression is now established. However, explanations for the efficacy of CBT are mixed. The evidence needed to support the explanation advanced by cognitive theory is lacking. This paper critically reviews the available empirical evidence. Forty-four outcome or process studies of therapy with depression are reviewed and 21 of these are subjected to a meta-analysis to investigate the relationship between change in cognitions and change in level of depression during different kinds of therapy. Our analysis shows that: (1) change in cognitive style occurs in all four categories of treatment: CBT, Drug Therapy, Other-Psychological Therapy, and Waiting List; (2) there was a significant difference between Waiting List and all the active treatments in change in cognitions, but not between active treatments; (3) the degree of change in cognitive style is significantly related to change in depression as measured by the Beck Depression Inventory (BDI), but not the Hamilton Rating Scale for Depression (HRS-D); and (4) the relationship between cognitive change and depression is not unique to CBT. Our findings show that CBT does provide some support for the cognitive models of depression but the relationship between cognitive change and recovery from depression is not unique to CBT.     

Contrast and reallocation of extraneous reinforcers as a function of component duration and baseline rate of reinforcement

Four pigeons responded on multiple schedules arranged on a “main” key in a two-key experimental chamber. A constant schedule component was alternated with another component that was varied over conditions. On an extra response key, conjoint schedules of reinforcement that operated in both components were arranged concurrently with the multiple schedule on the main key. On the main key, changes in reinforcement rate in the varied component were inversely related to changes in response rates in the constant component (behavioral contrast). On the extra key, some reinforcers were reallocated between components, depending on the schedules in effect on the main key in the varied component. In the varied component, the obtained rates of reinforcement on the extra key were inversely related to main-key reinforcement rate. In the constant component, extra-key reinforcer rates were positively related to main-key reinforcer rates obtained in the varied component, and were not a function of response rates on the extra key. In two comparisons, the rate at which components alternated and the value of the main-key schedule in the constant component were varied. Consistent with earlier work, long components reduced the extent of contrast. Reductions in contrast as a function of component duration were accompanied by similar reductions in the extent of reinforcer reallocation on the extra key. In the second comparison, lowering the rate of reinforcement in the constant component increased the rate at which extra-key reinforcers were obtained, reduced the extent of reinforcer reallocation, and reduced contrast. Overall, the results are consistent with the suggestion that some contrast effects are due to the changes in extraneous reinforcement during the constant component, and that manipulations of component duration, and manipulations of the rate of reinforcement in the constant component, affect contrast because they influence the extent of extraneous reinforcer real-location.     

Resistance to reinforcement change in multiple and concurrent schedules assessed in transition and at steady state

Behavioral momentum theory relates resistance to change of responding in a multiple-schedule component to the total reinforcement obtained in that component, regardless of how the reinforcers are produced. Four pigeons responded in a series of multiple-schedule conditions in which a variable-interval 40-s schedule arranged reinforcers for pecking in one component and a variable-interval 360-s schedule arranged them in the other. In addition, responses on a second key were reinforced according to variable-interval schedules that were equal in the two components. In different parts of the experiment, responding was disrupted by changing the rate of reinforcement on the second key or by delivering response-independent food during a blackout separating the two components. Consistent with momentum theory, responding on the first key in Part 1 changed more in the component with the lower reinforcement total when it was disrupted by changes in the rate of reinforcement on the second key. However, responding on the second key changed more in the component with the higher reinforcement total. In Parts 2 and 3, responding was disrupted with free food presented during intercomponent blackouts, with extinction (Part 2) or variable-interval 80-s reinforcement (Part 3) arranged on the second key. Here, resistance to change was greater for the component with greater overall reinforcement. Failures of momentum theory to predict short-term differences in resistance to change occurred with disruptors that caused greater change between steady states for the richer component. Consistency of effects across disruptors may yet be found if short-term effects of disruptors are assessed relative to the extent of change observed after prolonged exposure.     

The Unintended Negative Consequences of Sympathy for the Stigmatized1

Research on attitudes toward the stigmatized indicates that negative feelings and stereotypes toward the stigmatized are often mixed with positive feelings of sympathy and concern. Three studies investigate the hypothesis that positive outcomes for the stigmatized that are motivated by sympathy may have unintended negative consequences for self-esteem, affect, and motivation. Subjects were asked to imagine themselves in the position of a stigmatized person who received a job either because he or she was qualified, or out of sympathy for a stigmatizing condition. Results indicated that subjects reported lower state self-esteem, more negative affect, and lowered work motivation when the job was offered out of sympathy rather than on the basis of qualifications. Study 2 showed that the negative effects of sympathy occur whether the basis for the sympathy is prejudice and discrimination or mobility problems faced by the stigmatized individual. The third experiment showed that sympathy has negative effects when the sympathy is based either on individual or group-based problems imposed by the stigmatizing condition. The findings are discussed in terms of the attributional ambiguity surrounding positive outcomes faced by the stigmatized and applied to the effects of affirmative-action programs.     

Controlling the Ground Reaction Force During Lifting

The control of the ground reaction force vector relative to the center of gravity (CoG) was examined while subjects performed a back-lifting task. Six male subjects (aged 24.0 +/- 2.5 years) repeatedly lifted a barbell. A biomechanical analysis that used a linked segment model revealed that the summed rotations of body segments during lifting yielded a specific rate of change of the angular momentum of the entire body. This equaled the external moment provided by Fsubg; relative to CoG. This implies that multisegment movements involve control of the angular momentum of the entire body through an appropriately directed Fsubg;. Thus, in dynamic tasks Fsubg; is pointed away from rather than lined up with the CoG, as is the case in static tasks.     

The numbers game: Gender and attention to numerical information

Research suggests that males outperform females on standardized tests of math ability from early adolescence onward. Several explanations for this difference focus on the different experiences of females and males with numerical information. We reasoned that males have more experience with numerical information than females because typical male interests (e.g., sports) are more likely to involve numerical information than typical female interests (e.g., physical appearance). Thus, we predicted that males would attend more to numerical information than would females, at least when the information was presented in a male-related or gender-neutral context. Females were expected to attend more than males when the context was female-related. Results using White/Caucasian subjects provided some support for these predictions. Implications for future research on the relationship between the gender-linkage of math materials and gender differences in math performance are discussed.     

Testing Two Theoretical Explanations for the Attraction-Enhancing Effects of Self-Disclosure

The study investigated the differential ability of similarity theory and social exchange theory to predict the effects of self-disclosure in a counseling versus a friendship encounter The participants were 80 undergraduates. A 2 (counseling or friendship) × 2 (positive or negative disclosure) × 2 (relevant or irrelevant disclosure) design was used in which participants rated the videotaped self-disclosure of an individual in an initial dyadic encounter. Unequivocal support was not obtained for either of the theories, but relationship context (counselor vs. peer) influenced the effects of disclosure as measured on counselor-peer and relationship characteristics. A unique feature of the study was the use of the Client Reactions System (CRS) to measure participants' immediate reactions to self-disclosure. The CRS demonstrated both relationship context and valence of disclosure (positive or negative) effects.