Generalization decrement in human contingency learning

An association between a cue and an outcome will generalize to a similar novel cue to some extent, but not completely. Learning theorists refer to the discrepancy between responding elicited by the original cue and the novel cue as a generalization decrement. Two experiments used a contingency learning task with human participants to compare the size of a generalization decrement between configurations of cues that were altered by adding or subtracting compositional elements. The results suggest that adding elements to a configuration can produce a generalization decrement, but removing elements produces a more robust generalization decrement. Furthermore, the generalization decrement caused by adding elements was not likely to be caused by competing orienting responses. The results are used to contrast Pearce's (1987, 1994) and Wagner's (2003) models of stimulus generalization.     

Recovery from blocking between outcomes

Contemporary associative learning research largely focuses on cue competition phenomena that occur when 2 cues are paired with a common outcome. Little research has been conducted to investigate similar phenomena occurring when a single cue is trained with 2 outcomes. Three conditioned lick suppression experiments with rats assessed whether treatments known to alleviate blocking between cues would also attenuate blocking between outcomes. In Experiment 1, conditioned responding recovered from blocking between outcomes when a long retention interval was interposed between training and testing. Experiment 2 obtained recovery from blocking between outcomes when the blocking outcome was extinguished after the blocking treatment. In Experiment 3, a recovery from blocking between outcomes occurred when a reminder stimulus was presented in a novel context prior to testing. Collectively, these studies demonstrate that blocking of outcomes, like blocking of cues, appears to be caused by a deficit in the expression of an acquired association.     

Fictional narratives change beliefs: replications of Prentice,Gerrig, and Bailis (1997) with mixed corroboration

We report three exact replications of experiments aimed at illuminating how fictional narratives influence beliefs (Prentice, Gerrig, & Bailis, 1997). Students read fictional stories that contained weak, unsupported assertions and which took place either at their home school or at an away school. Prentice et al. found that students were influenced to accept the assertions, even those blatantly false, but that this effect on beliefs was limited to the away-school setting. We questioned the limiting of the narrative effect to remote settings. Our studies consistently reproduced the first finding, heightened acceptance of statements occurring in the conversations of narrative protagonists, but we failed to reproduce the moderating effect of school location. In an attempt to understand these discrepancies, we measured likely moderating factors such as readers’ need for cognition and their extent of scrutiny of the narratives.     

The expectancy model in the analysis of occupational preference and occupational choice

The differences between the factors related to occupational preference and occupational choice were explored for upper-division college students from business and psychology classes. The results strongly supported a valance-instrumentality-expectancy model in the context of occupational choice. Occupational preference was primarily a function of occupational valence, the multiplicative relation between the outcome valences and the instrumentalities of the occupations for these outcomes. Occupational choice was primarily a function of the force to choose an occupation, the multiplicative relaitonship between occupational valence and the expectancy of attaining an occupation and the expected costs of attaining an occupation.     

Effect of first-grade classroom environment on shy behavior,aggressive behavior,and concentration problems

Investigates the effect of the first-grade classroom environment on the shy behavior, aggressive behavior, and concentration problems of 609 children in 19 East Baltimore public schools. First-grade classroom environment was assessed in terms of dominant pattern of classroom achievement and behavior. Structured teacher ratings assessed child shy behavior, aggressive behavior, and concentration problems at the end of first grade. Children in low-achieving classroom environments had significantly higher teacher ratings of shy behavior and aggressive behavior than children in mixed-achieving or high-achieving environments, even after controlling for potentially confounding child characteristics and classroom behavior environment effects. Analyses controlling for child characteristics and classroom achievement environment effects indicated that children in poor-behaving classroom environments also had significantly higher teacher ratings of shy behavior than children who were not in poor-behaving environments. Subgroup analyses indicated that repeaters in mixed-achieving environments had significantly higher levels of shy behavior compared with nonrepeaters, and repeaters in poor-behaving environments had significantly higher levels of aggressive behavior compared with nonrepeaters. Implications for prevention research are discussed.     

The Effects of Numerical and Logical Group Size on Computer-Mediated Idea Generation

A laboratory experiment investigated the effects of numerical group size and logical group size (i.e., group heterogeneity in regard to task demands) on the performance of groups addressing an idea generation task while using computer-mediated communication. Six different numerical group sizes were studied, which ranged from 5 to 10 members. Logical size was manipulated by varying the amount of task-relevant information given to a particular group member. Larger logical group sizes (heterogeneous groups) were induced by distributing unique task-relevant information among group members; smaller logical group sizes (homogeneous groups) were induced by providing all task information to all members. A significant main effect for numerical group size showed that larger groups outperformed smaller groups. Numerical group size interacted with logical group size resulting in greater performance gains for increased numerical group size within heterogeneous groups. Average contributions per group member diminished with increased numerical group size for homogeneous groups and increased for heterogeneous groups.     

Emotional, physical, and sexual maltreatment in childhood versus adolescence and personality dysfunction in young adulthood.

The current study examined the unique relations of childhood and adolescent maltreatment (emotional, physical, and sexual) with DSM-III-R personality disorder (PD) dimensions in a sample of undergraduates. The results suggested that reported levels of childhood sexual maltreatment were uniquely related to six of the 11 PD dimensions examined. In contrast, reported levels of adolescent emotional maltreatment were uniquely related to only three PD dimensions and reported levels of adolescent physical maltreatment were uniquely related to only one PD dimension. Thus, whereas reported levels of adolescent emotional and physical maltreatment demonstrated some specificity to the various kinds of personality dysfunction, reported levels of childhood sexual maltreatment appeared to be related to more generalized personality dysfunction in young adulthood.     

Contrasting reduced overshadowing and blocking

Preexposure of a cue without an outcome (X-) prior to compound pairings with the outcome (XZ-->O) can reduce overshadowing of a target cue (Z). Moreover, pairing a cue with an outcome (X-->O) before compound training can enhance its ability to compete with another cue (i.e., blocking). Four experiments were conducted in a conditioned bar-press suppression preparation with rats to determine whether spacing of the X- or X-->O trials would differentially affect reduced overshadowing and blocking. Experiment 1a showed that reduced overshadowing was larger with massed trials than with spaced trials. Experiment 1b found that blocking was larger with spaced trials than with massed trials. Experiments 2a and 2b indicated that these effects of trial spacing were both mediated by the associative status of the context at test. The results are interpreted in the framework of contemporary learning theories.