Therapy set: Its effects on subjects' involvement in systematic desensitization and treatment outcome.

Abstract

The present study tested the hypothesis that therapy instructions significantly augment desensitization treatment effects by influencing subjects' involvement in the conditioning procedure. College snake phobics were randomly assigned to one of four treatment groups or a no-treatment control. Therapy set and involvement instructions were manipulated within a 2X2 factorial design in order to create therapeutically and experimentally oriented subjects who were either unencouraged or encouraged to work hard at the experimental procedure. Analyses revealed therapy instructional effects on both behavioral and self-report measures of fear change which could not be attributed to experimenters' awareness of instructional manipulations. Therapy oriented subjects' performance scores were not, however, significantly greater than those obtained by subjects with an experimental orientation. Alternative hypotheses and future research strategies for testing therapy instructional effects are discussed.

Expectancy and phobic level: Effects on desensitization.

“…A number of studies have been addressed to the role of expectancy in systematic desensitization (see reviews by Borkovec, 1973b;Lick & Bootzin, 1975;Rosen, 1976). Even though these studies seem to offer conflicting results, Rosen (1974Rosen ( , 1976 has suggested that much of the conflict can be resolved by distinguishing between two types of expectancy manipulations. In the first type, all subjects are informed that they are receiving a treatment procedure.…”

“…A total of nine studies (Lomont & Brock, 1971;Marcia, Rubin, & Efran, 1969;Mc-Glynn, 1971;McGlynn & Mapp, 1970;Mc-Glynn, Mealiea, & Nawas, 1969;McGlynn, Reynolds, & Linder, 1971b;McGlynn & Williams, 1970;Rosen, 1974;Wilson & Thomas, 1973) have failed to show significant differences between positive therapeutic instructions and neutral or negative therapeutic instructions accompanying desensitization. In addition, several studies have failed to find differences resulting from positive, neutral, and negative therapeutic expectancies when these differential expectancies were brought about through the administration of "therapy-boosting" placebo drugs (Woy & Efran, 1972) or bogus physiological feedback (Hewlett & Nawas, 1971;McGlynn, 1972;Nawas, 1972).…”

“…By way of contrast, the majority of the studies using the second type of expectancy manipulation have found significant effects on the outcome of desensitization. Specifically, six studies (Leitenberg, Agras, Barlow, & Oliveau, 1969;Miller, 1972;Oliveau, Agras, Leitenberg, Moore, & Wright, 1969;Persely & Leventhal, 1972;Rosen, 1974;Tori & Worell, 1973) have shown that therapeutic instructions produce significantly greater improvement than experimental instructions, whereas four studies (Borkovec, 1972;Mc-Glynn, 1971;McGlynn, Gaynor, & Puhr, 1972;McGlynn, Reynolds, & Linder, 1971a) have failed to show differences resulting from this expectancy manipulation. Lick and Bootzin (1975) have suggested that the latter four studies must be interpreted with caution, since only weak overall treatment effects were found in these studies.…”

“…As Wilkins (1973) has argued, it is impossible to conclude that expectancy has or has not affected treatment outcome when there are no measures taken of the impact of the expectancy manipulations. Only four studies (Marcia et al, 1969;Miller, 1972;Rosen, 1974;Wilson & Thomas, 1973) have used such expectancy measures, and only the studies by Miller and by Rosen were able to show a significant difference in subjects' expectancies. Not only is it important that future studies include independent assessments of subjects' expectancies, but it is also important that these assessments be accomplished in a more sophisticated fashion than in the past.…”

“…In addition to Rosen's (1974Rosen's ( , 1976 distinction between types of expectancy manipulations, a second major factor has been offered to account for the conflicting evidence regarding the role of expectancy in behavior therapy outcome. Borkovec (1973b) suggested that studies that have demonstrated an expectancy effect typically used subjects who were less phobic than studies that have failed to demonstrate such effects.…”