Effects of Playing Videogames on Children's Aggressive and Other Behaviors1

Noting the pervasiveness of videogames in American culture, the authors set out to examine the effects that playing videogames has on children. Thirty-one children were matched on sex, randomly assigned to play either a violent (karate) videogame or a nonviolent (jungle vine swinging) videogame, and then observed during free play. The main results were that the children who had played the jungle swing videogame later played more with a jungle swing toy and that the children who played the violent videogame later showed more aggression. The authors interpreted the findings as an indication that young children who play videogames later tend to act similarly to how their videogame character acted.     

Impulsiveness, attitude to authority, and gender.

This article examined the relationship between impulsiveness and attitudes toward institutional authority among Australian secondary school students. Reliable questionnaire measures of these constructs were completed by 48 boys and 57 girls, about 14 years of age. Correlations between impulsiveness and attitude to authority differed between the sexes, with a significant negative correlation of -.43 being obtained for boys only.     

Explicit contamination in “implicit” memory for new associations

In one view of implicit memory, priming arises from modification of preexisting representations; however, the role of such representations is currently in doubt following findings of implicit memory for newly formed associations. Closer consideration of studies reporting this effect, and of others that have failed to obtain it, suggests that such priming might result from the employment of explicit memory strategies. With measures designed to permit exclusion of such strategies, three experiments using lexical decision and stem-completion tasks found no evidence of truly implicit memory for unrelated pairs. Instead, priming was found only in those subjects (50% of the total in one experiment) who reported using explicit memory in stem completion. Contrary to previous conclusions, the results indicate a role for established representations in explaining implicit memory.     

Embedding instructive feedback into teacher-student interactions during independent seat work

The effects of embedding a constant time delay procedure into an independent seat work activity and using instructive feedback were evaluated in this study. Seven students with mild disabilities participated in the study that occurred in their special education classroom. A multiple probe design across sets of target behaviors was used, and students' responses to instructive feedback stimuli were evaluated during each probe condition. The procedures were implemented with a high degree of fidelity, and the results indicate that (a) the students acquired the target behaviors taught with the constant time delay procedure that was embedded into independent seat work, and (b) the students acquired some but not all of the responses to the instructive feedback stimuli. These findings are discussed in terms of using instructive feedback in classrooms and future research on instructive feedback.     

Lightness contrast in CRT and paper-and-illuminant displays

The increased use of CRT monitors for displaying and controlling stimuli in studies of surface color poses problems of comparability with data obtained with traditional paper-and-illuminant methods. A review of comparable studies using the two methodologies revealed that CRT studies tend to report larger contrast effects. To investigate factors that may be responsible for this difference, simultaneous lightness contrast was measured using both CRT and paper-and-illuminant presentations. The spatial distribution of luminance in the whole field of view and the visual angles subtended by the displays were controlled. The CRT presentation yielded contrast effects twice as big as those measured for a paper surface in a homogeneously illuminated room. However, a paper display under Gelb lighting yielded almost exactly the same effect size as that measured in the CRT presentation. These results demonstrate that contrast effects in both modes of presentation are affected by the spatial distribution of luminance beyond the basic experimental stimuli.     

Navigating in a challenging semiarid environment: the use of a route-based mental map by a small-bodied neotropical primate

To increase efficiency in the search for resources, many animals rely on their spatial abilities. Specifically, primates have been reported to use mostly topological and rarely Euclidean maps when navigating in large-scale space. Here, we aimed to investigate if the navigation of wild common marmosets inhabiting a semiarid environment is consistent with a topological representation and how environmental factors affect navigation. We collected 497 h of direct behavioral and GPS information on a group of marmosets using a 2-min instantaneous focal animal sampling technique. We found that our study group reused not only long-route segments (mean of 1007 m) but entire daily routes, a pattern that is not commonly seen in primates. The most frequently reused route segments were the ones closer to feeding sites, distant to resting sites, and in areas sparse in tree vegetation. We also identified a total of 56 clustered direction change points indicating that the group modified their direction of travel. These changes in direction were influenced by their close proximity to resting and feeding sites. Despite our small sample size, the obtained results are important and consistent with the contention that common marmosets navigate using a topological map that seems to benefit these animals in response to the exploitation of clustered exudate trees. Based on our findings, we hypothesize that the Caatinga landscape imposes physical restrictions in our group’s navigation such as gaps in vegetation, small trees and xerophytic plants. This study, based on preliminary evidence, raises the question of whether navigation patterns are an intrinsic characteristic of a species or are ecologically dependent and change according to the environment.

     

Aging and effect of predictability on reality monitoring

This study compared the direction of source confusions and the effect of predictability on reality monitoring for internally generated information and externally derived information in younger (mean age 19-25) and older (mean age 70-85) adults. Participants were invited to listen to the conclusions of simple stories or to generate and imagine them. Conclusions could be either highly predictable (Experiment 1) or unpredictable (Experiment 2). The change in predictability produced changes in the direction of source confusions only in older adults. When a story ended in a predictable way, older adults attributed to imagination conclusions that were actually perceived, whereas the pattern of confusions tended to reverse with unpredictable stories.