Effects of reinforcement schedules on rats' choice behavior in extinction.

The effects of reinforcement schedules on rats' choice behavior in extinction were studied. In a free-operant chamber equipped with two retractable bars, the experimental animals were trained to press the bars separately for a food reward. One bar delivered the reward on a continuous reinforcement (CRF) schedule, and the other delivered the reward on a partial reinforcement (PRF) schedule. Control animals earned the reward from both bars with the same reinforcement schedule, either a CRF or a PRF. When both bars were simultaneously available during extinction, the experimental animals responded more frequently to the CRF than to the PRF alternative, demonstrating a reversed within-subjects partial reinforcement extinction effect (PREE). A conventional between-subjects PREE was replicated in the control subjects. The results of this study were inconsistent with both Amsel's (1962, 1967) frustration hypothesis and Capaldi's (1966, 1967) sequential hypotheses.     

Brief group psychotherapy for the spousally bereaved: a controlled study.

A consecutive sample of mid- and late-life bereaved spouses were randomly assigned to treatment and no-treatment groups. Two hypotheses were tested: (1) that brief group psychotherapy during the early stages of loss would facilitate adjustment assessed by measures of mental health, positive psychological states, social role, and mourning; and (2) that positive effects would be maximized for subjects who were more distressed psychologically. Although group participants, compared with untreated controls, did over 1 year show modest improvement on role functioning and positive psychological states, overall the study failed to find substantial support for the two major hypotheses. Both experimental and control groups showed improvement over the year, particularly on measures of mental health and mourning. Differential benefit was not observed for the high-risk group.     

The effects of vicarious experience and stimulus intensity on pain termination and work avoidance

The purpose of the present investigation was to evaluate the role of vicarious experience in the acquisition of pain termination and work avoidance. Fifty-six experimental subjects were randomly assigned to view a film of a model who either terminated exposure to a pain stimulus and work task after 10 sec (high-avoidant) or 70 sec (low-avoidant). Following the film presentation, subjects were exposed to the pain stimulus and work task. Half of the subjects were randomly chosen to perform the task with a low-intensity pain stimulus (LP) and the other half performed the task while exposed to a high-intensity pain stimulus (HP). The results indicated that subjects in the high-avoidant model conditions (HA) did significantly less work and tolerated the pain stimulus for significantly fewer seconds compared to the low-avoidant model groups (LA). Subjects in the LP groups tolerated the pain stimulus significantly longer and did significantly more work compared to subjects in the HP groups. No significant interaction was observed. The results provide support for the hypothesis that behavioral reactions to pain can be acquired by vicarious experience. Implications for future research are discussed.     

Imaginative suggestibility and hypnotizability: an empirical analysis.

Hypnotic and nonhypnotic suggestibility were investigated in 2 experiments. In Experiment 1, nonhypnotic suggestibility was suppressed when measured after hypnotic suggestibility, whereas hypnotic suggestibility was not affected by the order of assessment. Experiment 2 confirmed a small but significant effect of hypnosis on suggestibility when nonhypnotic suggestibility was measured first. Nonhypnotic suggestibility was correlated with absorption, fantasy proneness, motivation, and response expectancy, but only expectancy predicted suggestibility when the other variables were controlled. Behavioral response to hypnosis was predicted by nonhypnotic suggestibility, motivation, and expectancy in a model accounting for 53% of the variance. Experiential response to hypnotic suggestion was predicted only by nonhypnotic suggestibility. Unexpectedly, hypnosis was found to decrease suggestibility for a substantial minority of participants.     

A linguistic deficit resulting from right-hemisphere damage

The ability of right-brain-damaged (RBD) subjects to correctly insert a word into a well-formed stimulus sentence was tested. Subjects also performed three evaluative tasks designed to establish their degree of general cognitive impairment. The performance of RBD subjects on these tasks was compared to that of left-brain-damaged (LBD) and non-brain-damaged (NBD) subjects. Although RBD subjects outperformed LBD subjects on the language-related evaluative tasks, the RBD group was significantly more impaired on a subset of the insertion task. This subset included items which required reassignment of the syntactic status of elements in the stimulus sentence in order for the insertion to be carried out. The results of this study permit refinement of the common characterization of RBD individuals as rigid in their interpretation of meaning and indicate right-hemisphere involvement in aspects of the grammar previously thought to be inaccessible to it.