Food-searching behavior of cats in a multiple-choice elimination problem

Twelve cats were individually exposed to a four-point elimination problem for 50 consecutive days. The problem for the animals consisted of choosing a series of different points where they found, and were allowed to eat, a piece of meat, without returning to any previously visited point. The order of elimination was not controlled in any way by the experimenter. Results indicated that cats were able to solve this problem. All subjects showed a strong tendency to make successive runs toward points situated as far apart as possible. Moreover, a relation was shown between performance and the tendency to follow this high divergence principle. This result is discussed in terms of subjects' ability to process information about the spatial characteristics of the experimental situation. This ability might in fact be related to the behavioral plasticity of animals in spatial problems according to the difficulty of the task.     

Social isolation as a punishment procedure: a controlled study

Contingent social isolation was investigated as a punishment procedure for the disruptive behavior of emotionally disturbed children in a classroom setting. The methodological limitations of previous studies were outlined, and alternatives adopted. Within a reversal and multiple baseline design, contingent social isolation was found to be an effective and relatively specific punisher. By introducing a new observation procedure, “pseudo-timeout”, it was determined that the punishing effect of social isolation was not attributable to observation artifact. A means for resolving the terminological confusion in the present use of timeout and social isolation was recommended.     

Differential reinforcement of interresponse times with controlled probability of reinforcement per response

Pigeons were presented food after interresponse times (IRTs) longer or shorter than a fixed percentage of their most recent IRTs. This procedure controlled probability of reinforcement per response while still allowing different classes of IRTs to be reinforced differentially. Support was found for IRT-reinforcement theory in that response rates were determined by the degree and direction of differential reinforcement of IRTs, but were relatively independent of probability of reinforcement per response and of the length of the control system's IRT memory. Stimulus control of these differential response rates was also demonstrated.     

Facilitation of human tobacco self-administration by ethanol: a behavioral analysis.

The effect of ethanol on the cigarette smoking of alcoholic subjects was studied in a residential laboratory. During daily 6-hr sessions, cigarettes were obtained either by request to the ward staff or by operation of a lever (fixed-ratio 5 or 10). In a mixed sequence across days, sessions involved ingestion of either vehicle (orange juice or vehicle plus ethanol (133.7 g). During ethanol sessions, the rate of cigarette smoking increased from 26% to 117% of vehicle levels. A series of control studies eliminated a number of potential behavorial mechanisms for the observed effect and indicated that the ethanol-induced increase in cigarette smoking occurred under a variety of experimental conditions: (1) when smoking could not occur concurrently with ethanol or vehicle consumption; (2) when subjects were not allowed to socialize; (3) when ingestion of ethanol or vehicle was scheduled for a number of consecutive days; (4) when various doses of ethanol were administered under blind conditions. In control experiments, weighing unsmoked tobacco and counting the number of puffs per cigarette indicated the effect was not due to smoking less of each cigarette. The effect was not limited to the experimental sessions alone, since total daily smoking was higher on ethanol days than vehicle days.     

The effects of a salient self-schema on the evaluation of proattitudinal editorials: Top-down versus bottom-up message processing

The effects of a salient self-schema on message evaluation were studied. Subjects were identified who characterized themselves using trait adjectives that reflected the prototype of either a “religious” or a “legalistic” person. Equally persuasive sets of proattitudinal messages were developed empirically using weak arguments. Half of the messages were developed to reflect a “religious” perspective on the issue (capital punishment, abortion) whereas half were developed to reflect a “legalistic” perspective on the issue. Religious and legalistic subjects were then exposed to religious or legalistic arguments supporting an equally acceptable position (e.g., eliminating capital punishment). Afterward, subjects evaluated the persuasiveness of the communication and listed their thoughts as part of a “curriculum development project.” Results suggested that subjects when exposed to a schema-relevant message arguments for a position in which they believed were more positive about the quality of the message arguments and in their cognitive responding. These data extend the heuristic value of selfschemata to the area of attitudes and suggest that cognitive responses in persuasion are subjectively rather than objectively rational.     

Generalized multivariate lens model analysis for complex human inference tasks

A generalized multivariate lens model is presented which will permit the analysis of complex human inference tasks. Such tasks, occurring in their natural ecology, may involve judgments or decisions on multiple criteria and/ or where the influence of theoretically interesting partitions or augmentations of cue profiles needs to be systematically delineated. The generalized model incorporates the standard, hierarchical, and fully partialed lens models, the initial elaborations of which were made by N. J. Castellan (1972, Organizational Behavior and Human Performance, 8, 242–261) and T. R. Stewart (1976, Psychometrika, 41, 101–120). Both multivariate and univariate lens model equations are presented within a common notational system. An example which demonstrates some aspects of the generalized model is discussed in detail. Other potential applications for the model are outlined.