Density and delay of punishment of free-operant avoidance

In two experiments, the free-operant shock-avoidance behavior of rats was punished by electric shock. Two aspects of the schedule of response-produced shock were varied: the frequency of punishment over time (punishment density) and the temporal interval between the punished response and the punishment (punishment delay). The general finding was that response-produced shock suppressed avoidance responding under most of the density-delay combinations studied, and suppression increased as a function of increases in density and decreases in delay. Rate increases of small magnitude also were observed, usually as an initial reaction to the lesser densities and longer delays. Response suppression, while decreasing the number of punishment shocks received, also increased the number of avoidance shocks, so that the total number of shocks received usually was greater than the minimal number possible. The results were discussed from the standpoint of similarities between the effects of punishing positively and negatively reinforced behavior. The finding that subjects did not minimize the total number of shocks suggested that when avoidance behavior is punished, responding is controlled more by the local consequences of responding than by overall shock frequencies during the course of the session.     

Processing of sequentially presented letters

The effect on the number of letters S can report of the duration of each sequentially presented letter was compared with that of processing time, defined as the time from the onset of a letter to the onset of the next letter. Four Ss were each shown 1250 common English words, from four to eight letters long, one letter at a time. Each letter acted as a visual noise field for the preceding letter. The duration of each letter and the interval between letters was varied independently. The S reported the letters he saw after each word was displayed. It was found that the processing time (onset to onset) predicted the number of letters correctly reported, regardless of the partition between on time and off time. A calculation was made of the number of milliseconds of on plus off time that are needed to ensure correct report of each letter. This time was independent of the duration of the processing time, but was positively correlated with the number of letters in the word. This correlation is probably in part artifactual, so that no claim can be made that it takes longer to process a letter of a long as compared to a short word.     

ACQUISITION OF EXPRESSIVE SIGNING BY AUTISTIC CHILDREN: AN EVALUATION OF THE RELATIVE EFFECTS OF SIMULTANEOUS COMMUNICATION AND SIGN-ALONE TRAINING

Two methods of training autistic children to use manual signs were compared. Two children, one mute and one capable of some verbal imitation, were taught to use signs as expressive labels for pictures of objects. Using an alternating treatments design, speed of sign acquisition was compared across two training conditions in which signs were presented either accompanied by, or without, the corresponding verbal label. In both conditions, the training procedure incorporated reinforcement, modeling, prompting, fading, and stimulus rotation. The efficacy of training in both treatment conditions was demonstrated by the use of a multiple baseline control across signs, but no clear differences in acquisition speed across conditions were apparent. Posttests conducted to assess stimulus control of signing, and learning of verbal labels when these were present in training, showed that the behavior of the imitative, but not the mute, child was controlled by the verbal stimuli. The implications of the results both for understanding deficits characteristic of autistic children and for developing appropriate language training procedures are discussed.     

Some problems in the study of differences in cognitive processes

To test whether groups differ in a particular ability, researchers often compare their performance on two tasks: an experimental task that is sensitive to the ability of interest and a control task that measures other influences on the experimental task. A group difference will be reflected in a differential deficit, a greater difference between groups in experimental task performance than in control task performance. Before concluding from such a result that the groups differ in the ability of interest, three methodological problems must be faced. First, a differential deficit may be an artifact of task differences in discriminating power. That is, the experimental task may be more sensitive than the control task to group differences in abilities other than the one of interest. Second, a differential deficit may be an artifact of group differences in familiarity with the stimuli or the task. Third, a group difference in one ability may be due to a difference in some other ability that is more, or less, general than the first. These problems affect research in a number of areas, including cognitive development, psychopathology, learning disabilities, and the theory of intelligence. We discuss some possible solutions to these problems.     

Caffeine ingestion,misattribution therapy,and speech anxiety

While theoretical analogs of misattribution therapy appeared promising (Nisbett & Schachter, 1966; Ross, Rodin, & Zimbardo, 1969), attempts with clinically relevant behaviors have not been so successful (Kellogg & Baron, 1975; Singerman, Borkovec, & Baron, 1976). Since the plausibility of the misattribution manipulation appears to be the central problem, the present study attempted to increase plausibility by manipulating familiarity with the setting and actual psychological arousal in a clinically relevant situation. Subjects only slightly fearful of giving speeches presented a speech in front of two observers. Familiarity was varied by having half of the subjects give a pretest speech, while arousal was manipulated by having half of the subjects ingest caffeine while the others ingested a placebo just prior to the test speech. The subjects' attributions were varied by giving them either arousal or irrelevant symptom instructions regarding the effects of the ingested drug. Direct suggestion rather than misattribution effects occurred: Those subjects receiving arousal symptoms reported more nervousness than subjects who had received irrelevant symptoms. The authors conclude that while the misattribution effect may have experimental validity, it is not effective with clinically relevant behavior.     

Aggression-inhibiting influence of sexual humor

Forty-eight undergraduate males participated in an experiment designed to investigate the hypothesis that prior exposure to sexual humor would reduce the level of aggression directed by angry individuals against the person who had previously provoked them. In order to examine this suggestion, subjects were first angered or not angered by a male confederate; next, exposed to either neutral, nonhumorous pictures or to one of two types of sexual humor (nonexploitative, exploitative); and finally, provided with an opportunity to aggress against this individual by means of electric shock. Results indicated that exposure to exploitative sexual humor, but not exposure to nonexploitative sexual humor, significantly reduced the strength of subjects' later attacks against the victim. These findings are discussed in terms of the results of a follow-up study suggesting that individuals are more likely to think or fantasize about exploitative than nonexploitative sexual humor following the removal of such stimuli.     

Chimpanzee language research: Status and potential

The impact of ape-language research upon current thought pertaining to language and man in relationship to the apes is discussed within an evolutionary framework. Studies of apes can reveal certain requisites to the language skills of humans. Social adaptations are thought to be important to the evolution of those requisites. A review of ape-language research is made, with emphasis given to the problems of controls where work is doneen face with the subjects, as where Ameslan (signing) is the system employed. The need for careful definition of what is a “word,” and the need for tracing through experience how responses come to acquire meaning, hence “wordness,” is emphasized. Levels of wordness are discussed which emerge initially from basic operants and performatives. Evidence is reported in support of the conclusion that it is through direct experience, through the pragmatic application and use of instruments, and through important social relationships that word learning is facilitated. Finally, it is noted that an important step of validation in our own work is in the successful application of methods emanating therefrom to work with mentally retarded children.     

The place of the human subject in the operant laboratory

Although laboratory study of human behavior seems an obvious vehicle for strengthening the scientific base of behavior analysis, the place of the human subject within the operant laboratory remains problematic. The prevailing research strategy has been to link principles developed with animals to human affairs, either through interpretation of naturally occurring human behaviors or through application of the principles to the solution of human problems. The paucity of laboratory research on human operant behavior derives from several misconceptions: the possibility that experimental demand characteristics and pre-experimental behavioral dispositions of human subjects contaminate the results; that ethical considerations place undue constraint on research topics and experimental designs; and that uncontrollable variation in subjects' histories and other relevant personal characteristics prevents observation of reliable functional relations. We argue that these problems do not pose insurmountable obstacles to the experimental analysis of human behavior; that adequate methods of control and analysis are available; and that operant techniques, by emphasizing experimentally imposed contingencies, are well suited for the laboratory study of human behavior.     

Talking about unemployment with school-leavers

Research is reported concerning the views of a variety of professionals as to appropriate ways of talking about unemployment with 16-year-old school-leavers. Preparation in schools for the possibility of unemployment is discussed, as well as issues for those in contact with young people without a job after they leave school. The ways in which professionals talk to young people about unemployment appear to vary substantially. The findings suggest that in adopting a particular approach a professional will be influenced by his beliefs about the labour economy, by his perceptions of young people's wants and needs, and by his own capacity to cope with the feelings involved in re-examining his role in relation to unemployed young people.