The Premack principle in human experimental and applied settings

Studies claiming support for the Premack Principle in human experimental and applied settings are reviewed in terms of the standard test conditions associated with the Principle and in terms of the Principle's conceptual constrains. Little definitive evidence was found to support the claim that a high probability response will reinforce a lower probability response, nor was the converse contention supported, that a low probability response will act as a punisher for a high probability response. More importantly, among the reports reviewed there was no evidence for the reversibility of the reinforcement relationship.     

Stimulus control of responding by response-reinforcer temporal contiguity

The stimulus properties of brief disruptions in response-reinforcer temporal contiguity were investigated using a discrete trial conditional discrimination procedure. Key pecking (nondelay) or key pecking followed by a brief interval of nonpecking (delay) in the sample component produced a stimulus change (choice component). Pecks in the choice component to one of two alternatives resulted in food or blackout, conditional upon which response requirement was met in producing the choice component. A baseline condition, in which key pecking always produced the choice component and correct choices were arranged randomly, alternated with experimental conditions that included nondelay and delay values of either 0.2, 0.5, or 1.0 sec between the last key peck and the initiation of the choice component. All subjects accurately discriminated brief temporal delays between a response and stimulus change, with choice accuracy increasing for three of four subjects as the temporal disruption in contiguity increase. Implications of the research for the study of delayed reinforcement, response-independent reinforcement, and the discrimination of causality are discussed.     

Evaluation and recall of evidence: Authoritarianism and the Patty Hearst case

By using the Patricia Hearst case as the stimulus material, two experiments were conducted to examine the relationship between authoritarianism and recall of evidence. In Experiment I it was found that high authoritarians recall more prosecution evidence than defense evidence. This was not the case for the low authoritarians. Results concerning the hypothesis that high authoritarians would recall more character information than low authoritarians were equivocal. In Experiment II a trend indicating that high authoritarians draw more direct inferences from incriminating evidence than do low authoritarians or an attorney was obtained. The results are discussed in terms of previous findings, authoritarian theory, and characteristics of the Patricia Hearst case.     

Resistance to satiation: Reinforcing effects of food and eating under satiation

It has been shown previously that rats which have learned a response when hungry will continue to make that response when tested satiated, a phenomenon labeled resistance to satiation. Here we showed that rats which were previously trained hungry will learn a new response for the opportunity to consume pellets in a new situation when tested satiated. In four experiments various groups received each of the components of the training given when rats learn an instrumental response when hungry. Rats were placed in the goalbox of a straight alley and given food pellets when hungry or were hungry only in their home cages prior to running a straight alley in the satiated test in Experiment 1. In Experiments 2, 3, and 4 learning of a differential conditioning problem for pellets in S+ (nonreward in S?) was measured in the satiated test. Groups given pellets in their home cages when hungry with or without alley exposure learned to run more rapidly in S+ than in S? in the satiated test phase. The tendency to eat pellets in the apparatus and the reinforcing effect of eating the pellets was larger for rats which ate the pellets when hungry in their home cage than for rats which ate the pellets when satiated in their home cage. Being hungry in the home cage with no pellets was not sufficient to produce eating or running for pellets in the satiated test, indicating that any inherent reinforcing effect of the pellets is not sufficient to produce eating or running, and that incomplete satiation cannot account for the learning. These data indicate that a reinforcing effect of eating pellets under satiation is an important determiner of resistance to satiation.     

The selective impairment of phonological processing: A case study

A case study is reported of an aphasic patient with fluent speech and markedly superior comprehension of written vs. spoken words. Results of extensive testing supported the hypothesis that the patient suffers from a phonological processing deficit that affects performance in all tasks that require the generation of a phonological code. This selective deficit is interpreted as the underlying cause of diverse symptoms such as asyntactic comprehension of written sentences, the commission of spelling errors in writing, and the production of literal paraphasias and neologisms in spontaneous speech. Alternative possibilities for the classification of this patient are discussed.     

A survey of communicative disorders students' attitudes toward stuttering

Cooper's (1975) Clinician Attitudes Toward Stuttering (CATS) inventories were conpleted by 1,902 speech-language pathology and audiology students from 33 universities, each in a different state. The majority of respondents perceived stutterers as having psychosocial problems and believed that client and parental counseling were essential aspects of treatment. These views were relatively unaffected by student training and clinical exposure. In addition, most of the assumptions of Johnson's diagnosogenic theory of stuttering were held by the majority of the students surveyed. Most of the respondents believed that stuttering was difficult to modify and that speech clinicians were neither adept nor comfortable treating stutterers. These latter attitudes were significantly affected by training, i.e., the more advanced the students' training, the more pessimistic their views on clinician competence. Other professional attitudes and the effect of training on them are also discussed.