Effect of preconditioning unconditioned stimulus experience on learned taste aversions.

One taste-aversion study using male Long-Evans rats in which ethanol was the unconditioned stimulus (UCS) and six studies in which lithium chloride (LiCl) was the UCS demonstrate that (a) exposure to the UCS prior to conditioning retards subsequent acquisition of learned taste aversions; (b) a single preconditioning UCS exposure is sufficient to attenuate conditioning; (c) the preconditioning UCS exposure must occur within a limited period prior to conditioning to attenuate learning; (d) repeated conditioning trials will override the effect of prior exposure to the UCS; (e) tolerance to the UCS is not a necessary condition for the attenuation effect to occur; (f) pairing the preconditioning UCS with a novel flavor other than the CS does not remove the preexposure effect, although it may reduce its magnitude; and (g) the degree of disruption is a positive function of preconditioning UCS dosage and an inverse function of conditioning UCS dosage.     

Conditioned inhibition is not the symmetrical opposite of conditioned excitation: A test of the Rescorla-Wagner model

Rescorla and Wagner's (1972) linear associative model of learning predicts that a neutral stimulus will become weakly excitatory if it is paired with a conditioned inhibitor and the compound is not reinforced. If the inhibitor is not allowed to extinguish during these pairings, the model predicts that the neutral stimulus will become strongly excitatory. Rescorla (1971) has presented some evidence to support the former prediction of a weak effect. Experiment I tested the latter prediction of a strong effect using rats in a conditioned emotional response paradigm, and found no evidence that the pairings made the neutral stimulus excitatory. Experiment II replicated Rescorla's results, but showed that even on a relearning test the experimental group learned no faster than a novel stimulus control group.     

Implications of measurement of eye fixations for a psychophysics of form perception

It was suggested that insights into feature analysis of processes involved in form identification might be gained from an analysis of eye movements made by Ss as they identified patterns. Fixations were measured during identifications of histoforms, polygons, and Vargus 10 figures. Eye fixations were measured, and Ss rated sections of the figures in terms of their importance. Eye fixations were measured in terms of number of changes and duration of fixations. The number of changes in fixation were found to reflect only individual differences. Duration of fixation was found to vary significantly with location within figures, with fixations being longest where changes of contour occurred. There was also a tendency to look longer at the top of polygons and Vargus 10 figures and at the center of histoforms. Ratings of importance were highest for sections of figures fixated for longer duration-generally areas in which changes of contour were present.     

The structure and reliability of the teacher temperament questionnaire

The Teacher Temperament Questionnaire is a recently developed instrument designed for personality assessment with preschool and early school children. The present study employed a sample of 116 in order to study the reliability and structure of the TTQ. A principal-components analysis yielded four well-defined components, which were labeled Compliance, Extraversion, Interpersonal Affect, and Environmental Sensitivity. These results did not support the theoretical scales. The component patterns were well defined and stable across the two administrations of the inventory. Internal consistency and test-retest reliability coefficients were determined for each of the four new scales. A second administration involving only items from the first three components provided a partial replication.An initial version of this paper was presented at the Northeastern Educational Research Association Meeting, Ellenville, New York, October 1979.     

A practical method for screening psychiatric disorder in children with speech and language disorders

Children with speech and language disorders have been found to have a prevalence rate of psychiatric disorder of 50%. The authors sought to develop an efficient screening procedure to distinguish such children who have psychiatric disorder and those who do not. Cutoff scores for easily administered parent and teacher behavior rating questionnaires were investigated in a population of 256 children with speech and language disorders and known presence or absence of psychiatric disorder. It was learned that when the questionnaires are used together, a cutoff score of 31 or greater on either questionnaire has a positive predictive value of 74.1 % and a negative predictive value of 76.1%. This screening method shows promise in assisting speech pathologists in comprehensive evaluation and treatment planning for children with speech and language disorders.     

Noise stress and circadian arousal in self-paced computation

Previous work(Frankenhaeuser & Lundberg, 1977) has shown that unpaced mental arithmetic is performed at slower rates in noise, despite unchanged catecholamine indices of arousal; only male subjects were used, tested early in the day. Since the times of testing entail arousal effects that interact with noise stress, and the sex of subject further modifies these interactions, a new experiment was designed to include these variables. Men and women were tested on the Norinder mental arithmetic task, in quiet or in noise, either in the morning, when arousal was low, or during the early evening, when temperature curves indicate that arousal should be high. Analysis of the number of problems attempted shows a significant drop for men in noise in the morning, but an interaction due to reversal of the noise effect in the evening; there is no main effect of noise when women's scores are included. The results are compatible with interpretations combining motivation and cognition, and they demonstrate the importance of the experimental variables in explaining noise stress effects.The authors are indebted to the late David A. Shipp for his assistance in running subjects.     

Extinction of the context and latent inhibition

The hypothesis that latent inhibition could be reduced by extinguishing the experimental context, that is, exposing the rats to the context between exposure to the conditional stimulus (CS) and conditioning, was tested. All experiments used the conditioned emotional response procedure. In Experiment 1, extinction was not effective when the animals were exposed to the clicker 40 times off the baseline of responding for food and when the clicker CS was partially reinforced with shocks during the test phase. In Experiments 2 and 3, latent inhibition could be reduced by extinction if the animals were exposed to the CS 24 or 16 times on-baseline, and if continuous reinforcement was used during the test. In Experiments 4, 5, and 6, we attempted to determine which variable was responsible for the discrepant results. In Experiment 4, extinction was effective with 20 or 40 on-baseline exposures to the CS, using continuous reinforcement during the test. In Experiment 5, extinction was not effective with exposure on- or off-baseline, using 24 exposures and partial reinforcement. Finally, in Experiment 6, extinction reduced latent inhibition using continuous, but not partial, reinforcement with 40 exposures off-baseline. From these results, we concluded that Wagner's model of habituation was not sufficient to account for latent inhibition and that a hybrid model, using both associative and cognitive representational processes, was necessary.     

A simple turntable for vestibular stimulation of cats by acceleration through a fixed angle with description of a head restraint

An inexpensive turntable for producing uniform angular accelerations for use in vestibular research is described. The table provides semicircular canal stimulation for cats or smaller animals at moderate accelerations above 3 deg sec^?2. A head restraint suitable for use on the table and designed for chronically implanted cats is also described.