A comparison of two methods of measuring conditioned taste aversions

Two methods of measuring conditioned taste aversions were compared. Following adaptation to a daily 10-min water drinking schedule, rats were made ill with an injection of cyclophosphamide after presentation of a novel-tasting fluid. Three days after this treatment, Ss were tested by (1) measuring the amount of the novel fluid consumed on the continuing 10-min access schedule or (2) measuring their preference between plain water and the novel fluid. When the drinking behavior of the conditioned animals was compared with that of appropriate controls, the preference method proved to be the more sensitive.     

Stimulus control in the experimental study of cooperation

The cooperative responses of pairs of human subjects were reinforced under several stimulus conditions in two settings designed to require a "social" response, i.e., where at least one of the two persons is responding to the behavior of the other. The first task, designed by Lindsley and Cohen, required individual responses within 0.5 sec of one another for reinforcement. The second (modified) task required a delay of 3 sec between individual responses. To determine dependence of cooperation on social stimuli, rates of cooperative behavior on these tasks were compared in the presence and absence of a stimulus indicating to each subject the other's response and a stimulus which indicated the duration of the timeout after reinforcement. The results indicated that only in the modified task was a high rate of cooperation always contingent upon the presence of the social stimuli.     

The design and operation of an improved olfactometer for behavioral and physiological investigation1

An improved olfactometer is described, and its range of application for the study of the olfaction in man is discussed. The apparatus is based on air dilution; an odorant is diluted in a constant-flowing stream of air. The odor-containing air flows to S, who is seated in an enclosed partition with his head in a Plexiglas hood. A visual signal system allows communication between E and S. Precision flowmeters, solenoid valves, one-way floats, and an automated control system permit E to select rapidly a large range of stimuli, stimulus concentrations, and trial lengths. The apparatus has been used in a variety of situations ranging from absolute threshold detection to adaptation and recovery.     

Laboratory experimentation at the center for computer-based behavior studies

The Center for Computer-Based Behavioral Studies (CCBS) is designed around a time-shared computer system to make its informational and technological resources available to behavioral scientists and policy analysts at remote locations (through the ARPA Network and through dial-in phone lines) as well as in our own laboratory. The principal goal of CCBS is to broaden and expand the capabilities and horizons of behavioral research for studying problems of real-world complexity and theoretical relevance. The principal focus is on strengthening laboratory and associated research methodologies through computer-administered multiperson experiments and gaming simulations.     

Positive contrast obtained in reacquisition following interpolation of nonreinforced or partially reinforced trials

Two experiments investigated the effects of shifting from either nonreinforcement or partial reinforcement (PRF) to continuous reinforcement conditions (CRF). In the first experiment, three groups of rats were given food reinforcement under CRF conditions in a runway followed by regular extinction trials (RE), extinction trials where Ss were delayed for 30 sec before entering the empty goal box (DE), or CRF trials where Ss were delayed for 30 sec before entering the baited goal box (DF). Then all Ss were run on the delayed reinforcement condition (DF). In the final delayed reinforcement condition, group DE ran significantly faster than group DF, reflecting positive contrast. In the second experiment, four groups of rats were trained in a runway to receive either 4% or 18% sucrose reinforcers under either PRF or CRF conditions. Then all Ss were transferred to a Skinner box and bar presses were continuously reinforced, with each S continuing to receive the same sucrose concentration as before. The former PRF Ss, regardless of the reinforcer, bar pressed at a significantly higher rate in the Skinner box than the former CRF Ss. The evidence seemed to favor the view that the effectiveness of a reinforcer is not an absolute, unchanging quantity but rather depends on the historical context in which the reinforcer occurs.     

Factorial invariance and significance

It is shown that invariance requirements remove the indeterminacy in factor determination and lead to an integration of factorial studies with promise of considerable reduction in computational labor. The selection of significant primary factors is discussed, with special reference to Thurstone's simple structure criterion.     

The Cracks Are Where the Light Comes in

The sensitivity of psychotherapists in understanding others is connected to a deep capacity for both intimacy and vulnerability. The three papers by Lauren Levine, Deborah Dowd, and Sharon Ziv Beiman present clinical experiences with women patients that touch deep areas of openness for patient and analyst alike. Through their generous and evocative material, and the invitation of a male discussant, all parties are drawn into a powerful sense of mutual vulnerability. Painful mis-attunements occur and are courageously addressed by the writers. The discussion uses the poetic allusion, to the cracks in everything, as the necessary basis for the light of analytic relatedness and love to come into being.