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.     

Lithium-mediated disruptions of latent inhibition: Overshadowing by the unconditioned stimulus in flavor conditioning

In a series of experiments, the ability of a single lithium preexposure to disrupt CS effectiveness was assessed using a latent inhibition procedure. Lithium preexposure administered proximal (90 min) to a saccharin familiarization trial reduced latent inhibition whereas a similar administration more distal (360 min) to flavor familiarization failed to do so. Additional experiments demonstrated that this socalled “US overshadowing” effect was not attributable to sensitization (Experiment 2), excitatory backward conditioning (Experiment 3), or state dependency (Experiment 4). The implications of US overshadowing for proximal US-preexposure effects are discussed.     

Relative deprivation and referent cognitions

Determinants of relative deprivation were examined in a laboratory experiment. Discontent associated with relative deprivation was hypothesized to be a function of likelihood, or the perceived probability of actually obtaining a desired outcome under existing circumstances, and referent cognitions, which involve the subjunctive probability of obtaining that outcome under alternative (hypothetical) circumstances. Male and female undergraduates discovered that their alleged chances of receiving experimental credit were either poor (low likelihood) or good (high likelihood). They also learned that if a different procedure had been used, their chances of receiving credit would have been either poor (low referent) or good (high referent). Responses to a subsequent questionnaire indicated that whereas discontent did not differ by referent conditions under high likelihood, greater discontent was shown by low-likelihood/high-referent subjects than by low-likelihood/low-referent subjects. This low- versus high-referent difference under low likelihood was also found in two conceptual replications designed to eliminate any influence of social comparison. The relevance of this model to other findings and theoretical formulations is discussed.     

Characteristics of taste-mediated environmental potentiation in rats

When rats drink a novel flavor in a distinctive environment and are injected with lithium, potentiated aversions are established to the environment as evidenced by the animals' unwillingness to consume a familiar, nonaversive flavor in this environment. Experiment 1 demonstrates that this potentiation is due to the presence of both the distinctive taste and the environmental cues on the conditioning trials, not simply aversive conditioning to each element or to generalization between the two elements. This potentiation phenomenon was shown to be sensitive to the novelty of the potentiating flavor in Experiment 2. Experiment 3 demonstrated that second-order conditioning is difficult to establish using these procedures, although Experiment 4 revealed that postconditioning extinction of the aversive flavor interfered substantially with environmental potentiation. These outcomes are discussed in terms of their implications for adaptive adjustments in feeding behavior as well as for more general conceptions of associative learning.     

Response persistence in the rat following intermittent punishment and partial reward: Effects of trial sequence

Thirty-six rats were given 16 days of partial reward training in a runway. During the final 12 days each of the animals received one foot-shock experience each day. One group received shock on an N trial preceding an R trial (P-R), a second group was shocked on N trials not followed by an R trial (R-P), and the third group received shock after completing all daily trials (Control). Following acquisition the rats were split within each group (one half received 24 trials of unpunished extinction and one half continued to receive partial reward but were punished on every trial). During consistent punishment the P-R animals were more persistent than the R-P or Control rats and during unpunished extinction the P-R and Control animals were equal in persistence but both were superior to the R-P animals. The results were discussed in terms of Capaldi's sequential trial theory.     

Interference with ingestional aversion learning produced by preexposure to the unconditioned stimulus: Associative and nonassociative aspects

Preconditioning exposure to a lithium chloride unconditioned stimulus (US) interferes with the subsequent conditioning of a taste aversion. Multiple US preexposures produce a long-lasting or durable interference with aversion learning, whereas a single US exposure produces a transient interference effect. The present experiments demonstrate that the durable US preexposure effect is substantially reduced if the method of drug treatment (infusion versus injection of the drug into the peritoneal cavity) or the spatial cues present during drug treatment (home cage versus a distinctive environment) are changed between the preexposure and taste conditioning phases of the experiment. In contrast, these manipulations do not attenuate the proximal/transient US preexposure effect. These findings indicate that different mechanisms are responsible for the two US preexposure effects. The results are consistent with previous suggestions that the durable effects of lithium preexposure are due to associative interference produced by the exteroceptive stimuli that accompany drug administrations and indicate that the proximal/transient US preexposure effect is mediated by nonassociative mechanisms.     

Spatial localization in children after changes in position

Five experiments investigated the young child's ability to retrieve a target after a change in the position of the child or the target. In Experiments I–IV 2- to 4-year-old children were rotated 90, 180, 270, or 360° about a stationary square table containing four identical hiding locations at each of the cardinal locations. The children tested performed this task significantly better than chance, but their errors reflected either their response biases in the absence of any information as to the location of the target, or the repetition of a response which had been successful in retrieving the target prior to the change in position. When the children were forced to respond rapidly, these errors increased significantly. In Experiment V a table top was rotated 90, 180, 270, or 360° in front of 3- to 10-year-old children. There were two cue situations. The child saw the rotation, or the child had to infer the rotation. Young children made errors of the types observed in Experiments I–IV. The ability to inhibit these errors increased with age. By 7 years of age performance was virtually perfect when the child could observe the change in position of the hidden object. The ability to infer the positional change developed more slowly and was good but not perfect at 10 years of age.     

Effects of two types of response-contingent time-out on compliance and oppositional behavior of children.

The present study examined the effects of two time-out (TO) procedures, within-room and out-of-room, on compliance and oppositional behavior. Subjects were 24 nonclinic 5-year old children and their mothers. Mother-child pairs were assigned to one of three groups (within-room time-out, out-of-room time-out, or control) and observed in a laboratory setting under each of three experimental conditions: pretraining, training, and posttraining. The results indicated that, relative to the control group, both out-of-room and within-room TO reduced oppositional behavior and increased compliance. The two time-out procedures were equally effective in changing the two target behaviors; however, the within-room approach required significantly more administrations of time-out than the out-of-room technique.     

Interaction of reinforcement conditions and developmental level in a two-choice discrimination task with children

A total of 540 first, fourth, and eighth graders, equally divided by sex, were run on a two-choice discrimination task under one of three reinforcement conditions: reward (R) for correct responses, punishment (P) for incorrect responses, or reward and punishment (RP) for correct and incorrect responses. Half the Ss were tested by a male E; half, by a female E. Across all developmental levels, learning was superior in the P group. Complex interactions involving sex of S and E underline the importance of organismic variables in discrimination learning and in specifying parameters of reinforcer effectiveness.     

Further test of a subjective probability model of social inference

Subjects read paragraphs suggesting that a fictitious person (O) either did or did not possess an attribute X. Then, they reported their beliefs that they would like O (P_L), that O possessed X (P_X), that O was intelligent (P_I) and that O was sarcastic (P_s). Other beliefs necessary to test the predictive accuracy of Wyer's subjective probability model of cognitive organization were also reported. The model accurately predicted P_L on the basis of beliefs about X (the attribute to which information about O directly pertained); this accuracy was greater than that obtained in an earlier study in which real persons were evaluated, and did not depend upon the favorableness of X. However, predictions of P_L based upon beliefs about O's intelligence overestimated obtained values, while predictions based upon beliefs about O's sarcasm underestimated these values; moreover, P_I and P_S were underestimated and overestimated, respectively, by beliefs about X. It was speculated that these discrepancies were due to temporary inconsistencies among beliefs resulting from the information presented which did not have time to be resolved before beliefs were reported. Changes in P_L, P_I, and P_S resulting from additional information about X were accurately predicted in all cases. Implications of the model for other formulations of social evaluation processes are noted.     

Induction of intellectual gains in blind children

Twenty blind children (5–10 years old) were taught the concept of seriation by a learning set procedure. Ten of the children were also taught a simple classification concept to see if developing both abilities would produce more general intellectual gains. Children in a control group had training sessions matched in timing and extent, but differing in content. The results indicate that mastery of the concepts of seriation and classification can be accelerated through training. Training also affected WISC and SIT IQ scores; for these measurements, the seriation-classification group showed the greatest increase. Training had no effect on measures of psychological and social adjustment. The findings suggest that learning set training of Piagetian concepts can be effective in overcoming some conceptual deficiencies found in blind children. It may be profitable to test similar procedures with other children who are biologically mature but lagging in conceptual development.     

Psychoactive drug effects in a hyperactive child: A case study analysis of behavior change and teacher attention

The effects of methylphenidate on the behavior and teacher interactions of a 9-year-old hyperactive female were analyzed. Observations of the subject's task-related and disruptive behaviors and of interactions between the subject and her classroom teacher were made when the subject received the active drug and an inert placebo. Teacher's ratings of the subject's classroom behavior and measures of her academic performance were also obtained. Results showed that when the subject was receiving methylphenidate she engaged in task-related activities a greater percent of the time, had a higher percent of teacher interactions that were instructional in quality, and received lower behavior ratings by the teacher than when she was receiving a placebo. The results suggest that the use of medication may enable the hyperactive child to profit both behaviorally and academically.     

Transfer of effort across behaviors

A series of experiments investigated the effects of required force and number of responses per reinforcer upon the subsequent performance of a second behavior. In the first experiment, a group of rats required to complete five round trips in an alley per food pellet subsequently bar-pressed for food at a greater rate than a group rewarded for each round trip or a control group that did not receive the alley experience. In the second experiment, a group required to apply a 70-g bar-press force subsequently shuttled for food at a greater rate than a group required merely to touch the lever or a control group that did not undergo the lever-press manipulation. The third experiment found that the force effect persisted across all five test sessions and was attributable to differences both in response speed and interresponse time. The fourth experiment found that both the necessary bar-press force and number of bar presses per reward affected subsequent shuttling in extinction. Two alternative interpretations of these results were compared: (a) the degree of accustomed effort per reinforcer becomes a generalized component of instrumental behavior or (b) high effort increases the habituation frustration-produced disruptive responses.     

Social elicitation of infant vocal behavior.

The time course and the nature of social elicitation of vocalizations in 3-month-old infants were analyzed. Adult stimulation produced an immediate and significant increase in both the rate and the percent of bursts of vocal sounds of eight infants (Experiment 1). Both response-independent and response-dependent social stimulation were effective in producing increased rates of vocalizations, but only when each of four infants could see the eyes of the adult who delivered the social stimulus (Experiment 2).     

Methodological issues in language acquisition research with very young children

It is suggested that the dominance of observational methods in child language research with very young children has limited progress in understanding the language acquisition process. Evidence is presented that, contrary to popular belief, naturalistic methods do not guarantee ecological validity, nor are they free of task biases. Furthermore, observational studies do not necessarily provide better measures of linguistic competence than do more structured methods. Instead, it is argued that new insights from cognitive developmental research are applicable in studying language production in children younger than 3 years. A number of structured techniques are reviewed that have been used or could be used to study language production. It is concluded that a combination of methods is necessary in order to disentangle and control the many variables that enter into the language acquisition process.     

The modification of racial bias in preschool children

In previous studies using the Preschool Racial Attitude Measure (PRAM) and other measurement procedures, preschool children have displayed a tendency to evaluate light-skinned (Euro-American) persons more positively than dark-skinned (Afro-American) persons. Both Euro- and Afro-American children demonstrate this pro-Euro/anti-Afro ($\text{E+}\text{A?}$) bias, though it is less pronounced among Afro children.Two experiments designed to modify this racial bias are reported. The first study involved 39 Euro- and Afro-American preschool children and employed operant learning principles to modify $\text{E+}\text{A?}$ bias via a teaching machine procedure which provided reinforcement for pro-Afro/anti-Euro responses. Following training, the children showed a reduction in $\text{E+}\text{A?}$ bias on a test procedure not associated with the training. Follow-up testing of 30 of the children approximately 1 yr after the posttest revealed a tendency for the pro-Euro bias to be partially reestablished. The second study involved 70 Euro-American kindergarten children and was concerned with the modification of $\text{E+}\text{A?}$ bias via a classroom curriculum procedure and the possible influence of the race of the teacher associated with the curriculum. The experimental curriculum, designed to develop positive associations to dark-skinned persons and to the colors black and brown, was shown to have no effect on $\text{E+}\text{A?}$ bias, nor was race of teacher a variable of significance. Possible explantations for the findings of both experiments were discussed.     

Neuroelectrical correlates of categorical speech perception in adults

Auditory evoked potentials were recorded from the left and right hemispheres of 16 adults during a phoneme identification task. The use of multivariate statistics enabled researchers to identify a number of cortical processes related to categorical speech perception which were common to both hemispheres, as well as several which disinguished between the two hemispheres.     

An examination of disciplinary procedures with children

In Experiment I the effect of the contingent application of negative attention (a verbal reprimand plus a brief period in which the authority person glares intently at the child) and repeated commands on the noncompliant behavior of children was examined. Thirty-two mother-child pairs served as subjects. The results indicated that negative attention decreased noncompliance whereas repeated commands did not. In Experiment II the effectiveness of negative attention, isolation, ignoring, and a combination of procedures (the alternate use of isolation, ignoring, and negative attention with the same subject) in reducing noncompliance and maintaining it at a low level during a recovery period was examined. Twenty-eight mother-child pairs served as subjects. The results indicated that each of the four disciplinary procedures reduced noncompliance. However, negative attention was associated with less off-task behavior than the isolation and combination procedures when discipline was being imposed and a lower level of noncompliance than ignoring during recovery, whereas the combination condiiton was the only procedure that maintained noncompliance during recovery at the treatment level.