Mediators of the effects of magnitude of reinforcement

The characteristics of mediational mechanisms based upon magnitude of reinforcement were investigated using rats. In two experiments, two-choice discriminations were trained in which selections of one lever in one external stimulus and a second lever in another external stimulus were reinforced with food. In the first experiment, it was found that the discrimination was acquired more rapidly when one choice was reinforced with a large number of food pellets and the other with a smaller number of pellets than when other configurations of reinforcement magnitude were provided. In the second experiment, reversal of a two-choice discrimination was found to be facilitated by prior exposure of the animals to the reversed relationships between the external stimuli and magnitudes of reinforcement. These results were consistent with predictions from a stimulus or associative view of anticipatory processes based upon magnitude of reinforcement.     

The effectiveness of visual and gustatory conditioned stimuli in human classical aversive conditioning with electric shock

Thirty-six undergraduate volunteers, divided into three equal groups, were given electric shock while sipping a colored, unflavored solution (Group I): a flavored, colorless solution (Group 2); or a colored, flavored solution (Group 3), in order to determine whether human Ss respond differentially to visual and gustatory cues when the UCS is aversive electric shock. Using a standard classical discrimination procedure, the CS + was blue water for Group 1, citric acid solution for Group 2, and blue citric acid solution for Group 3. For all groups the CS- was plain water, which was never paired with electric shock. The dependent variables were derived from Staats' A-R-D theory: attitudinal change (A) and a performance measure of sip-size taken during conditioning trials (D) both confirmed the hypothesis that taste can be an effective CS when the UCS is shock, in contrast to results typically obtained with rats where visual but not taste cues are effective with a shock UCS.     

A developmental and cross-cultural study of the influences of rule structure and problem composition on the learning of conceptual classifications

Five experiments were conducted permitting direct comparisons in the way Ss of different ages and cultures solved conceptual problems. One group of problems (Traditional) could be solved using a reference rule of conjunction or disjunction. Another group of problems (Intradimensional) could be solved either by one of the reference rules, or by a structurally simpler rule. Analysis of American performance confirmed that older Ss not only solved using the simpler rule more often than younger Ss, but when they did so they solved faster. For both American age groups, solution using the simpler rule led to no difference in performance between conjunctive and disjunctive Intradimensional problems. Conjunction proved easier than disjunction only for the Traditional problems. Unlike Americans, the Kpelle of Liberia did not solve using the simpler rule, and found conjunction easier than disjunction for both Traditional and Intradimensional problems. When a memory aid was provided the Kpelle showed a pattern of performance exactly like Americans.     

A comment on Koriat,Averill, and Malmstrom's “individual differences in habituation”

The paper considers the issues, raised by Koriat et al. (1973), of the consistency and reliability of measures of habituation currently used in personality research. It is argued that the problem of reliability is not as serious as Koriat et al. proposed and that specificity of measures of habituation is a theoretical rather than a methodological problem. It is proposed that ambiguity in the literature on the personality correlates of habituation is more likely to be due to the failure to consider the effects of stimulus conditions on habituation than to the problems of reliability and specificity.     

Defensive burying of aversive fluids in rats: The effects of peripheral anosmia

Three experiments were conducted in order to determine the role of olfactory stimulation in defensive burying of aversive fluids in rats. The results revealed that zinc sulfate-induced anosmia eliminated burying of fluids paired with lithium chloride as well as an inherently aversive solution. This occurred despite the fact that the rats avoided consuming them. These data indicate that defensive burying of aversive fluids is governed by olfactory stimuli and confirms an earlier report, which indicted that burying does not occur in response to aversive gustatory stimuli.     

Sex-typed play of toddlers in a day care center

By the age of 3, boys prefer gross motor and vehicle play and girls prefer doll and housekeeping play. The present study was an attempt to define the age at which these sex differences first appear by observing the play behavior of one- and two-year-olds in a day care center. We observed use of stereotyped toys in children 15 to 35 months old during free play. Boys played more with the masculine toys than with either of the other types, whereas girls showed almost equal use of all three types. Choice of sex-typed toys was more prevalent among older boys, while older girls showed less play with feminine toys than younger girls.     

The use of natural consequences and a make-up period to eliminate school phobic behavior: A case study

The school-phobic behavior of a seven-year-old male was modified through implementing a program characterized by maximum parental involvement, restructing of natural consequences, and the use of a make-up period. Full-time school attendance was achieved on the sixteenth day of the program. The advantages of using school personnel as monitors and not as disciplinarians of the school-phobic child's behavior are discussed.     

The effect of imagining an event on expectations for the event: An interpretation in terms of the availability heuristic

Previous studies have indicated that explaining a hypothetical event makes the event seem more likely through the creation of causal connections. However, such effects could arise through the use of the availability heuristic; that is, subjective likelihood is increased by an event becoming easier to imagine. Two experiments were designed to demonstrate this principle. In Experiment 1, subjects asked to imagine Jimmy Carter winning the presidential election (prior to the election) predicted that he was more likely to win than subjects asked to imagine Gerald Ford winning. In Experiment 2, subjects asked to imagine a good college football season for the previous championship team were more likely to predict a major bowl bid than subjects asked to imagine a bad season, although the effect did not appear in predictions of the season record. In both studies, subjects who were also asked to explain the imaginary event were no different from subjects who only imagined. Several other attributional distortions are interpreted in terms of the availability heuristic.     

Developmental changes in the semantic processing of pictures and words

Second- and fifth-graders' semantic decision times for pictures and words were analyzed relative to the predictions derived from unitary- and dual-memory models. At both grade levels, word-word response latencies were greater than picture-word latencies which, in turn, were greater than picture-picture latencies. An interaction between Grade and Condition indicated that verbal access times decreased more than pictorial access times. The data fit the predictions of a memory model postulating category storage in a single memory system as opposed to simultaneous representation in verbal and nonverbal memory systems. It was concluded that with increasing experience verbal access to this single semantic system is more rapid.     

Delayed recognition memory for orientation by human infants

The familiarization/novelty preference paradigm was employed to study the effect of a delay (between the end of the familiarization phase and the beginning of the test phase) on discrimination of the orientation of square-wave gratings by 2- and 3-month-old human infants. Three stimulus pairs were studied: horizontal-vertical, non-mirror-image obliques, and mirror-image obliques. The data indicate that the members of the oblique-oblique stimulus pairs are confused in memory to a greater extent than the members of the horizontal-vertical stimulus pair. These findings are consistent with P.C. Bomba's (1984, Journal of Experimental Child Psychology, 37, 609-636) recent report that infants respond to the orientation of a visual stimulus in a categorical-like manner.     

Taste-mediated potentiation of noningestional stimuli in rats

Holtzman rats drank saccharin in a distinctive environmental chamber prior to lithium-induced toxicosis. This treatment was administered four times. These animals subsequently drank less water or familiar saline in the chamber than animals which received water in the environment during conditioning. In addition, these environmental stimuli blocked the formation of a lithium-mediated coffee aversion more if they were conditioned in the presence of saccharin than if they were conditioned in the presence of water. Such differential blocking provided further evidence that the presence of a taste during conditioning facilitated aversion learning to the environmental chamber.