Stimulus selection in passive avoidance learning and retention: weanling, periadolescent, and young adult rats

Periadolescent rats exhibit a number of behavioral differences in comparison with younger or older animals. For instance, periadolescents tend to show enhanced acquisition of simple active avoidance tasks, but impaired acquisition of more complex appetitive and aversive discriminations. In this experiment, rats were trained on a simple passive avoidance task at one of three ages, as weanlings (25 days), periadolescents (35 days), or young adults (45 days). Training occurred in the presence of both a redundant discriminative stimulus and a specified, redundant contextual stimulus. The periadolescents did not differ from either younger or older rats in rate of learning the passive avoidance task. The retention performance of these animals was then tested following a change in either, neither, or both of the redundant cues. When a measure of performance that controls for baseline activity was used, it was observed that periadolescents were not disrupted by a change in the redundant discriminative stimulus, a cue change that clearly disrupted performance in 25- and 45-day-old animals, and tended to be more disrupted by the contextual change than younger or older rats. It is hypothesized that the alterations in performance exhibited by periadolescents may be related to an ontogenetic alteration in stimulus selection modulated by the catecholaminergic systems.     

Increased novelty-induced grooming in aged rats: a preliminary observation

Age-related changes in grooming activity in female Fischer-344 rats were observed in a home cage and in a novel testing chamber for 50 min. Compared to the home cage condition with brief handling treatment, excessive grooming was found in the novel situation. The amount of novelty-induced grooming of aged rats (26-28 months) was about two times that of young animals (6-8 months). This increase in novelty-induced grooming of aged animals was attributable to an increase in the number of grooming bouts, prolongation of each grooming bout, and a slight increase in the duration of licking elements. However, there were no age differences in the percentage of face washing and the duration of face-washing elements. These results are discussed in terms of behavioral aging and age-related changes in peptidergic pathways in the brain.     

Interrogative suggestibility and delinquent boys: An empirical validation study

This study has several aims. First, to validate the Gudjonsson Suggestibility Scale (GSS) among delinquent and adolescent boys placed in an assessment and short-term treatment centre. Second, to test the hypothesis that adolescent boys are particularly susceptible to suggestions when they are ‘pressured’ by negative feedback and instructions. Finally, to investigate the hypothesis that suggestibility is related to memory recall and self-esteem. The GSS was administered to 31 boys (ages 11 to 16 yr) who had been independently rated by two teachers on measures of suggestibility and self-esteem. Suggestibility as measured by the GSS was found to correlate significantly with the teachers' ratings of suggestibility, supporting empirically the criterion-related validity of the GSS. Compared with young ‘normal’ adults the boys were no more likely to give in to suggestive questions than the adults, unless their performance was subjected to criticism and negative feedback. The results suggest that deliquent adolescents may be particularly responsive to interpersonal pressure during interrogation. The findings have important implications for police interrogation procedures.     

Development of differences in response latencies to right and left visual fields

Robust lateralization developed in right-handed adults who were asked to judge letter pairs as "same" or "different" during 4608 trials. By the end of the first two blocks (768 trials) "same" responses were favored when presented in the RVF (transmitted directly to the left hemisphere) and "different" responses were favored when presented in the LVF (transmitted direction to the right hemisphere). This gradually reversed over sessions with "same" responses becoming faster for letters presented in the LVF, and "different" responses becoming faster for stimuli presented in the RVF. The laterality acquired under these conditions was cumulative and reproducible, appeared in all 16 subjects, and was preserved between sessions a week apart. The data suggest that laterality is a flexible and reversible characteristic of the human brain even when stimulus and task remain constant.     

The effects of empathic instructions upon donating behavior: Sex differences in young children

First-grade children were given either empathy instructions (in which they were told to imagine themselves in the target person's place) or neutral instructions (in which they were told to listen to what the target person did). For half the subjects, the target person was of the same sex; for the other half, the target person was of the opposite sex. Subjects were then given a chance to anonymously donate money to the target child, who was presented as being in need. Liking for the target child, subject's perceptions of the target child's emotional state, and subjects' report of their own emotional states were also assessed. Empathic instructions increased donating behavior for males, but not for females. Accuracy of perception of the target person's state was generally high. Self-reports of emotional states congruent with that of the target tended to be associated with increased donating behavior only for males, but these self-reports were greater for females than males, and greater for both sexes with same-sex target persons. Liking also was enhanced by gender similarity. These results are discussed in terms of a proposed relationship among empathy, prosocial behavior, sex, and age.We wish to express our gratitude to the staff and students of Wannamaker and North Fairview Elementary Schools of Topeka, Kansas, for their assistance in carrying out this research, and also thank C. Daniel Batson for his helpful suggestions and comments.     

Self-efficacy,nicotine-fading/self-monitoring and cigarette-smoking behaviour

An attempt to replicate and extend the successful results of Foxx and Brown's (1979) nicotine-fading, self-monitoring procedure for smoking abstinence or controlled smoking was undertaken using a combination of their procedure and cognitive-behavioural interventions. The latter consisted of: (1) a variation of Meichenbaum's (1977) self-instructional training and (2) a simple, direct manipulation of Bandura's (1977) concept of self-efficacy. Evidence was found to support Foxx and Brown's (1979) procedure with respect to reduced smoking rate and nicotine/tar intake. Combinations of treatments did not result in an enhancement of these effects. However, with respect to smoking abstinence, comparable results were only found in groups receiving specific training in self-efficacy. It was suggested that the variability of findings in this study as well as those in the literature subsequent and relating to Foxx and Brown's (1979) procedure might be accounted for using Bandura's (1977) self-efficacy concept.     

Non-accidental injury to children—I: A review of behavioural interventions

The history of the growth of interest in child abuse in the Western World over the last two decades is described chronologically. Problems of definition of a phenomenon which is a deviation from social norms are discussed, including the problem of distinguishing acceptable discipline from abuse. The literature on parent-training approaches to the treatment of abusive parents is reviewed. It is argued that researchers in the U.S.A. and the U.K. are working within different statutory frameworks, from different definitional criteria and with different conceptualizations of successful outcome. The need for multiple outcome measures, in terms of quality of life for the abused child, and for long-term follow-up is stressed, together with the importance of clinical experience in the planning and execution of evaluative treatment research.