Extinction of a conditioned emotional response: massed and distributed exposures

Using the lick-suppression methodology of Jacobs, Buttrick & Kennedy (Pavlovian Journal of Biological Science, 23, 29-34, 1988), a conditioned emotional response (CER) was established in 24 rats using off-the-baseline pairings of a light (the conditional stimulus) and brief footshock (the unconditioned stimulus). Following conditioning, the rats were assigned to one of three extinction groups differing in whether they received massed or distributed off-the-baseline exposure to the conditional stimulus. The effects of differential treatment were assessed on-the-baseline on test days, when the extinction of the CER was monitored. Rats receiving a single, long exposure to the conditional stimulus showed greater resistance to extinction than the rats in the distributed groups. They also showed a difference pattern of CER extinction. The results were discussed and compared to similar studies that have explored the massed vs distributed dimension, both in CER and avoidance-extinction (using response prevention or flooding). The relation of animal studies to parallel human studies using exposure therapy was also discussed.     

Reaction to Self-Attributed Victim Responsibility: A Comparative Analysis of Rape Crisis Counselors and Lay Observers1

This research examined observers' reactions to sexual assault victims engaging in different forms of self-attributed responsibility. Theory and research suggests that behavioral responsibility contributes positively to the coping process of victims, whereas characterological responsibility impedes it. For observers in the present study, the expression of either type of self-responsibility by a rape victim resulted in a more negative impression of the victim's emotional well-being and greater attribution of responsibility to the victim in comparison to a victim relying solely on chance explanations. Moreover, this bias was evident among rape crisis counselors as well as lay observers. Discussion considered the implications of such biased perceptions for sexual assault victims and the need for a fuller understanding of the nature of self-attributions of responsibility by victims.     

UNDER WHAT CIRCUMSTANCES CAN A UNIONIZED COMPANY USE TESTING FOR PROMOTION?1

A job-related, “fair test” of ability, when used as one tool and not as the sole determining factor, has been established by arbitrators to be an appropriate selection instrument. If a test has been determined as being job-related (i.e., related to the actual performance of the job), has been administered and scored both fairly and consistently, it will be considered a “fair test.” Generally, in unioncompany contracts that mention testing, a “fair test” contains the above qualifications. Arbitrators have indicated that the union involved should be afforded the opportunity to see the test; it was made quite clear, however, that the union should not have the test. In all cases reviewed, tests were upheld by arbitrators when they (1) were “fair tests,” and (2) did not conflict with the contract language. Past testing practice was not a determining factor when these two conditions existed. A total of 69 cases between 1953 and 1967 have been found relevant–27 from 1953 to 1962 and 42 from 1963 to 1967. In the first study, 13 cases were lost by a company; in six of these cases a company violated the union-company contract and in seven cases the test used did not qualify as a “fair test.” A total of twelve cases were lost by a company in the second study; in two cases a company violated the union-company contract and in ten cases the test used did not qualify as a “fair test.”     

Taste rejection of nonnutritive sweeteners in cats.

Cats reject saccharin and cyclamate and are indifferent to dulcin, although they, like other mammals, prefer sucrose. The rejection threshold for saccharin found in this experiments, .0001 M, is about 2 log steps lower than a previously reported rejection threshold for sodium saccharin. Water produces a taste in cats adapted to their own saliva. The high sodium saccharin threshold may have resulted because the taste of the sodium saccharin was masked by the taste of the water solvent; however, saccharin may also be somewhat more aversive to the cat than sodium saccharin. Saccharin may produce an aversive taste because it stimulates receptor sites sensitive to substances bitter to man as well as those sensitive to sugars. In addition, saccharin may not be an effective stimulus for all sugar-sensitive sites.     

On models with variable universe

In this paper some parts of the model theory for logics based on generalised Kripke semantics are developed. Löwenheim-Skolem theorems and some applications of ultraproduct constructions for generalised Kripke models with variable universe are investigated using similar theorems of the model theory for classical logic. The results are generalizations of the theorems of [4].     

Constraints on Pavlovian aversive conditioning: Implications for avoidance learning in the rat

Four experiments investigated the relative degree of control exerted by several conditional stimuli when each stimulus: (a) preceded shock, (b) followed shock, and preceded a shock-free interval, (c) was independent of shock, or (d) was novel. When the onset of an auditory stimulus had preceded shock (Experiments 1, 2A, and 3), it always exerted conditioned excitatory control. When the same stimulus preceded a shock-free interval, it never exerted conditioned inhibitory control. When the onset of light (Experiments 2B, 4), silence (2C), or darkness (1, 2D) preceded a shock-free interval, it always exerted conditioned inhibitory control. However, when one of the latter stimuli preceded shock, it failed to exert excitatory control. Several models of this phenomenon were tested. The implications of these results for the species-specific defence reaction and two-factor theory accounts of avoidance learning were outlined.