Freezing as an avoidance response: Another look at the operant-respondent distinction

Groups of rats were trained with shock either contingent on freezing (punishment procedure) or contingent on not freezing (avoidance procedure). Although the different contingencies produced different levels of freezing behavior, these levels were attained immediately rather than over a number of trials. This result, together with the results of control rats, suggest that while freezing can be controlled by both punishment and avoidance procedures, in both cases the effects on freezing are due to elicitation rather than learning.     

Deprivation level affects extinction of a conditioned taste aversion

Hooded rats were conditioned to avoid drinking saccharin by following exposure to saccharin with injection of cyclophosphamide, a drug that produces visceral upset. Extinction trials were then given by presenting saccharin without cyclophosamide injections with the rats under low (10 hr) or high (23 hr) fluid deprivation. The aversion extinguished in fewer trials in rats under high deprivation.     

The opponent-process theory of motivation: VIII. Quantitative and qualitative manipulations of food both modulate adjunctive behavior

The present studies extend the opponent-process theory of acquired motivation to the schedule-induced polydipsia paradigm and more generally to adjunctive behavior. The theory suggests that manipulations of the quality and the size of the pellet presented on an intermittent schedule should be important modulators of polydipsia. In Experiment 1, presenting animals with preferred, less preferred, or least preferred food pellets on a fixed-time 120-sec schedule resulted in progressively lower levels of water intake. In Experiment 2, the quality and size of the pellet were manipulated factorially. These variables were found to interact in the control of both the development and maintenance of schedule-induced drinking. Thus, predictions from the opponent-process theory were supported by these findings.     

Language and speech recovery in a case of viral encephalitis

The speech and language recovery course of a 47-year-old man with viral encephalitis is described. Over a 3-month period, the patient was evaluated six times using the same selected battery of tests. Results show that viral encephalitis can deleteriously affect communicative performance and that improvement in medical status is accompanied by rapid and dramatic gains on most standard speech and language measures. For this case changes appeared related to improved auditory attention and retention, increased efficiency in word retrieval, and improved mental status.     

Affiliativeness: A trait measure in relation to single-act and multiple-act behavioral criteria

The validity of trait affiliativeness is examined. Based on an assertion related to attitudes, it was predicted that a trait measure would predict a single-act criterion worst, a repeated measure of a single act better, and a multiple-act criterion best. The prediction was confirmed, supporting the notion that traits are, as originally conceived, good predictors of broadly based behavioral tendencies but not necessarily of isolated acts.     

Conservation learning and the differential impact of visual information available during and after modeling

In order to investigate the nature of the processes that promote the observational learning of conservation, nonconservers were allowed or not visual access to the conservation stimuli while an adult model verbalized the conservation rule. In addition, after each demonstration the subjects were submitted to one of four conditions. The first three conditions involved a short pause during which the observers respectively kept seeing the stimuli, had to visualize them mentally, and had to visualize mentally some irrelevant stimuli; no interruption occurred in the fourth condition. As predicted, the withdrawal of visual information at the time of rule exemplification was accompanied with lower learning scores. However, equivalent acquisition was found with respect to each of the conditions in which the subjects were invited to examine specific stimuli after rule modeling. Altogether these data were discussed in terms of the greater and lesser extent to which the conditions permitted the children, during the observational training, to practice covertly the modeled solution.