Several studies have shown that the strength of classically conditioned fear varies inversely with the length of the CS-UCS interval (McAllister & McAllister, 1971). If fear conditioning is important in the vicious-circle (VC) phenomenon (Brown, 1969; Melvin, 1971; Mowrer, 1947), then the interstimulus interval between brightness cues (CS) and shock (UCS) may similarly affect VC behavior. Experiment 1 examined effects of brightness cue change on VC responding. Forty male hooded rats were assigned to four groups in a 2 x 2 design, using the presence or absence of shock in the third segment during extinction and the presence or absence of cue change as independent variables. Experiment 2 examined the effects of pre-shock brightness cue changes on VC behavior, and varied the interval between the cue change location and shock. Eighty male hooded rats were assigned to eight groups in a 2 x 4 design, using the presence or absence of shock in the third segment and cue change placement as independent variables. The results indicated that brightness cue changes can reduce VC behavior. Experiment 2 also demonstrated that a cue change in the first alley segment reduced vc·responding as effectively as a total alley cue change. Changing the lower startbox cues was less effective and changing Segment 2 cues had little effect on VC behavior. The results were consistent with the ISI effects found in conditioned-fear research, since there was a relationship between the strength of VC responding and the spatio-temporal interval between changed cues and shock. / Master of Science

The goal of this experiment was to examine the pattern of ACh release in mPFC and HPC during performance in trace and delay appetitive conditioning.

This thesis will discuss Pavlovian conditioning and its utility in researching various areas of psychology including interpersonal attraction. It was designed to extend the application of conditioning principles in the study of interpersonal attraction by testing cue competition predictions made by the reinforcement-context theory of attraction.

Traditional two-process theory predicts that a conditioned stimulus (CS) paired with shock offset on Pavlovian trials will inhibit operant avoidance responding. Two explanations of the inhibitory mechanism involved were compared: contemporaneous pairing of CS with a hedonic relief reaction versus the predictive, discriminative relationship of CS to the non-shock interval. The pattern of avoidance inhibition associated with cessation CSs paired with electric shocks of constant duration was expected to be different from the pattern accompanying cessation CSs paired with shocks of variable duration. Mean rates of responding by the two groups were compared by analysis of covariance using baseline as the covariate. Neither CS displayed any reliably observable effects on avoidance rates. Possible procedural flaws and compatible improvements are discussed.

An avoidance response was conditioned to three stimuli presented in serial order. Following conditioning, each group of subjects received a different treatment procedure. The group I procedure involved distributed CS trials, contingent, non-anxious CS terminations, and individualized treatment durations. Group 2 subjects received massed CS trials, non-contingent CS terminations, and non-individualized treatment durations. Group 3 subjects experienced distributed CS trials, contingent non-anxious CS terminations, and non-individualized treatment durations. Individual izing treatment duration (termination contingent upon operational ized measure of anxiety dissipation) was found to significantly hasten the extinction of avoidance responses. Implications for the effective practice of implosive therapy were discussed. Yoked control methods were criticized for confounding the variable of individualization of the yoked variable.

An experiment was conducted to study the role of "positive expectancy" when utilizing anxiety-relief conditioning. Fourteen male and female undergraduate psychology students were selected as subjects (Ss), based on pre-test scores obtained on the "Snake Intimacy Test" (SIT). Ss were matched according to pre-SIT scores and randomly assigned to the "positive expectancy" or "no expectancy" groups. Anxiety relief conditioning was administered without variation. Only the rationale given each group describing what was transpiring was different. The statistical results revealed significant improvement by both groups. Also, the "positive expectancy" group improved significantly over the "no expectancy" group. Therefore, "positive expectancy" is apparently a sufficient, but not necessary, variable of anxiety-relief conditioning.

One of the newer techniques to be utilized in the treatment of a variety of behavioral disorders is anxiety-relief conditioning (Thorpe, Schmidt, Brown, and Castell, 1964; Solyom and Miller, 1967; Wolpe and Lazarus, 1966). In its theoretical formulation, reciprocal inhibition by anxiety-relief is similar to Wolpe's reciprocal inhibition by progressive relaxation (Solyom and Miller, 1967). Whereas Wolpe's method utilizes Jacobsonian relaxation principles to provide the medium through which anxiety is reciprocally inhibited, the procedure employed in anxiety-relief conditioning utilizes the relief following termination of an aversive stimulus to set an occasion which will permit reciprocal inhibition to take place. Many of the problems encountered in relaxation induction and control are thus avoided (Wolpe, 1958; Thorpe et al., 1964). Anxiety-relief conditioning appears to have been successful in patients that previously had been unsuccessfully treated by psychotherapy and chemotherapy for as long as 20 years (Myers, 1957; Thorpe et al., 1964; Solyom and Miller, 1967). Solyom and Miller reported successfully treating six of seven phobic patients who complained of severe depression, difficulty in interpersonal relationships and anxiety attacks when meeting people, as well as excessive fear of crowded places. These patients had an average length of illness of 11.1 years, ranging from 2 to 20 years. Patients were treated for a mean of 19.5 sessions with no evidence of symptom substitution or reappearance of the phobic fear upon follow-up (Solyom and Miller, 1967). Although the authors cited above have all reported case studies of successful therapeutic applications of anxiety-relief conditioning techniques, there have been few experimental studies of the efficacy of this technique. A recent experiment failed to refute the hypothesis that noxious stimulation and/or habituation, rather than aversion-relief, contribute to the beneficial therapeutic effects noted. This study left unanswered the question of which variables contribute to aversion-relief conditioning (Solyom, L., McClure, Heseltine, Ledwidge, and Solyom, C., 1972). The present study was undertaken to further explore the relevant variables in aversion-relief conditioning. It was hypothesized that reduction of fear to a phobic stimulus would be significantly greater among subjects who viewed the phobic stimulus while experiencing the pleasant sensation associated with aversion-relief than among subjects who viewed the phobic stimulus after the effects of aversion-relief had presumably dissipated.

The study was designed to find a response on the behavioral level that would be an effective index across subjects for determining when conditioned aversive suppression of a response had been achieved. Ten male volunteers received shock during trials in which they had to smoke. Half of the subjects received a brief but more intense shock when they stopped smoking during a trial. A comparison of these subjects to the others showed their average amount of smoking suppression in pre- and post-treatment rates to be significantly (P < .025) greater. In addition, these subjects showed conditioned emotional responding. It was concluded that this behavioral level response was an effective index for determining when suppression of smoking would occur.

This paper explores research on the misinformation effect and hypothesizes a new explanation for the occurrence misinformation effect. Current psychological theories states the misinformation effect occurs when memories are skewed by the presentation of new information after an initial event. This effect has been tested in a multitude of ways, including testing words lists, pictures, colors, and change blindness. Socially, the misinformation effect has been used to explain the inaccuracies of eyewitness testimony. The current judicial system relies on the fallible memory of people and has wrongfully imprisoned numerous innocents. The purpose of this research is to show the misinformation effect is not a problem with memory storage and retrieval, but rather a product of selective stimulus control.

Many people who receive exposure-based treatments for anxiety disorders exhibit a return of fear and avoidance which is often referred to as renewal or relapse. Human and nonhuman research on fear conditioning and renewal has been instrumental in helping understand relapse in anxiety disorders. The purpose of this investigation was to examine renewal of human avoidance and assess whether avoidance may aid in sustaining renewal of fear responses. We adopted a multimodal measurement approach consisting of an approach-avoidance task along with ratings of perceived threat and fear and measures of skin-conductance, a widely used physiological measure of fear. A traditional, single-subject research design was used with six healthy adults. All tasks employed a discrete trial procedure. Experimental conditions included Pavlovian fear conditioning in which increased probability of money loss was paired with a “threat” meter in Context A and later followed extinction in Context B. Fear and avoidance increased to higher threat levels in Context A but not Context B. Renewal testing involved presenting the threat meter on a return to Context A to determine if it evoked fear and avoidance (i.e., relapse). As predicted, renewal testing in Context A showed that increased threat was associated with increased avoidance, ratings of perceived threat and fear, and higher skin-conductance. Moreover, results showed that renewal maintained over six blocks of trials. This is the first investigation of renewal of threat and avoidance in humans that highlights avoidance as a mechanism that may contribute to maintaining fear in anxiety pathology.