CS duration,amount, and concentration effects in conditioning taste aversions

The relative contributions of the duration, amount, and concentration of a taste CS were assessed in pairings with an ionizing radiation US in two experiments. Increasing the duration of the CS (0.1% saccharin) up to 9 min yielded increasingly better conditioning over a $\text{1}\text{2}\text{-}\text{hr}$ CS-US delay interval. When the concentration of the sacharin was increased, only a few seconds' exposure to the CS was necessary for near asymptotic conditioning. It was observed that the CS duration effect had not been identified earlier because most investigators utilize 10–20 min CS access periods. The role of CS duration in conditioning over a delay was discussed with reference to the probability of the memory of the CS being present at the time of the pairing with the US event.     

Effects of schedule and magnitude of reinforcement under conditions of thirst motivation

In contrast to a recent finding (Macdonald, G. E., & De Toledo, L. Learning and Motivation, 1974, 5, 288–298.) the results of three experiments investigating various partial reinforcement (PRF) manipulations under conditions of thirst motivation demonstrated strong similarity to analogous manipulations involving food reward. Specifically, for animals receiving water reinforcement, PRF was shown to generate greater resistance to extinction than continuous reinforcement (Expt 1 & 3), the schedule of reinforcement was shown to interact with level of acquisition (Expt 1 and 2), and the magnitude of the partial reinforcement extinction effect was shown to be a function of reward magnitude (Expt 3). These results provide strong evidence that mechanisms which operate in partial reinforcement situations are highly similar, regardless of the type of appetitive reinforcement.     

Effect of CS-US pairings on shock-elicited aggression as a function of US intensity

In two experiments with paired rats, the effect of superimposing CS-US pairings on a baseline of shock-elicited aggression was studied. Baseline shocks (3.0 mA, 0.125-sec duration) occurred at a rate of 20 shocks per min throughout each session. In Experiment I, each independent group of two pairs of subjects received (in addition to baseline shocks) US shocks of 1.0, 3.0, or 5.0 mA and 5-sec duration, each shock signalled by a 1-min CS. At all three US intensities, aggression increased during the CS. In Experiment II, pairs of subjects received each unconditioned stimulus intensity in a within-subjects design. This procedure revealed a direct relationship between rate of responding and unconditioned shock intensity.     

The effects of stress on state and trait anxiety in emotionally disturbed,normal, and delinquent children

The effects of stress on trait and state anxiety of emotionally disturbed, normal, and delinquent children were assessed using the State-Trait Anxiety Inventory for Children (STAIC). This scale measures both transitory feelings of apprehension and tension that vary over time as a function of situational stress (A-State) and individual differences in the disposition to experience such anxiety states (A-Trait). Results indicated that A-State increased as a function of stress, whereas A-Trait was relatively stable and impervious to the temporary effects of stress. Use of the STAIC with normal and deviant populations was supported.     

Stimulus probability and same-different classification

Three experiments investigated the effect of stimulus probability on same-different classification time. In Experiments I and II, subjects made same responses on the basis of name matches of simultaneously presented letters. Half of the same trials involved letters that were also physically identical. Experiment I showed that the presentation probability of specific letters affected name matches and different responses, but not physical matches. Experiment II varied stimulus contrast as well as probability. Contrast had a main effect but did not interact with probability at any level of processing. In Experiment III, subjects were switched to the physical level of processing. Stimuli that now had the same name but differed in case were called different. In this condition, the probability effects obs(irved in Experiment II disappeared. These results are interpreted as demonstrating that stimulus probability has its effect during the process that derives the name of the stimulus from the visual representation. This process takes place before the name comparison is made, and the name comparison process precedes the determination of the different response.     

Psychosocial maturity and interpersonal attraction

Psychosocial maturity (PSM), assessed by scores on the Inventory of Psychosocial Development, was related to interpersonal behavior. In Experiment I PSM and proportion of attitude similarity was varied using Byrne's attraction paradigm in a between-subjects design. The personality variable failed to affect attraction. In Experiment II PSM and proportion of attitude similarity were manipulated in a within-subjects design. High PSM subjects rated the stranger significantly higher in attraction at high levels of similarity and significantly lower in attraction at low levels of similarity when compared to Low PSM individuals. The results were discussed in terms of design differences in personality research and potential mechanisms by which PSM affects attraction (self-esteem and/or competence).     

The cheating and intention of a partner as determinants of evaluative decisions among juvenile offenders

Male juvenile offenders were asked to evaluate the work of an experimental partner (confederate) who completed a work task four times. The work partner cheated on two trials and did not cheat on two trials while working for a charity (one cheat and one noncheat trial) or for selfish gain (one cheat and one noncheat trial). It was found that subjects rated the work done on cheating trials lower than work done on noncheating trials. In addition, subjects shared less reward money on cheating trials relative to noncheating trials. However, the intentions of the confederate, defined as the reward recipient, failed to affect subjects' judgments. These results were described as supporting previous studies which have indicated that delinquents fail to take account of others' intentions when making moral judgments.