Opioid-reinforced operant behavior: selective suppression by alpha-methyl-para-tyrosine.

Morphine-addicted rats performed operant responses for opioid or milk rewards. When rats were then denied access to opioids, abstinence symptoms developed. Responding under extinction conditions 2 wk. after opioid withdrawal provided a measure of the "relapse" tendency. Systemic administration of DL-alpha-methyl-para-tyrosine, an inhibitor of catecholamine synthesis, suppressed these responses if they had been reinforced by an opioid but not if they had been established with milk reinforcement. This indicates that the integrity of the catecholamine systems is vital for relapse to occur.     

Memorability, word frequency and negative recognition

Brown (1976) has provided an analysis of the effect of the memorability of an item on the confidence with which it is accepted or rejected in a test of recognition or recall. When the subject has no clear recollection of the inclusion of an item in an input list, he is assumed to evaluate its memorability in the context of the experiment before he decides whether to accept or reject it. If the judged memorability is high, the absence of a clear recollection is stronger evidence against the item than if it is low. A specific prediction is that memorable distractors in a recognition test will be more confidently rejected than non-memorable ones. This prediction was tested and confirmed in three experiments in which recognition was tested by 4-category rating. Except in Experiment I, items memorable to individual subjects were identified by administering a questionnaire. For example, in Experiment III forenames of immediate family were assumed to have high memorability. This experiment also included word frequency as a variable. Low-frequency distractors were rejected significantly more firmly than high-frequency distractors: extraction of memorable names enhanced this effect. The relationship of memorability to word frequency is discussed.     

A stereotaxic implant technique for the weanling rat

A modified technique for permanently implanted electrodes in the weanling rat is presented. As a reliable and durable technique, long-term stimulation of the juvenile rat is made possible.     

Working with the institutionalized aged and their families: Considerations for clergy

The institutionalization of an aged parent presents unique challenges and strains to the family system. It also provides opportunities for limited intervention and support by empathic clergy. It is often difficult for middle-aged children to understand some of the strong and often sudden emotions they experience regarding their institutionalized parents, particularly as these feelings become confused with their own sense of having reached middle age. Again, opportunities present themselves for clergy to be sensitive to these confusing feelings.     

Influences of test expectations on memory-processing strategies

In a series of four experiments, recall and recognition performance were examined following recall and recognition instructions. It was found that recall-instructed subjects produced significantly better performance than recognition-instructed subjects on tests of ordered and free recall of words, particularly on the early part of the list (Experiments 1 and 2). The results of two further experiments suggest that this is mediated by differences occurring at input, and is due to increased rehearsal by subjects expecting a recall test (Experiments 3 and 4).