Age-Correlated Incremental Consideration of Velocity Information in Relative Time-to-Arrival Judgments

One hundred fifty-one children and 43 adults judged which of 2 cartoon birds would be the first to arrive at a common finish line. Objects moved unidirectionally along parallel trajectories, either at the same or different speeds, and disappeared at different distances from the goal. Overall, 9–10-year-old children performed as well as adults, but 4–5- and 6–8-year-olds erred significantly more often. On trials for which distance to goal at disappearance was a valid cue, 4–5-year-olds scored 80% correct, and no differences were seen between 6–10-year-olds and adults. On the opposite type of trials, where the trailing bird would win the race, only adults retained their level of performance, and all age groups differed markedly. Findings suggest a gradual developmental transition from a distance-based to a time-based understanding of the task.     

Differential induction of c-Jun and Fos-like proteins in rat hippocampus and dorsal striatum after training in two water maze tasks

Research examining the neuroanatomical bases of memory in mammals suggests that the hippocampus and dorsal striatum are parts of independent memory systems that mediate "cognitive" and stimulus-response "habit" memory, respectively. At the molecular level, increasing evidence indicates a role for immediate early gene (IEG) expression in memory formation. The present experiment examined whether acquisition of cognitive and habit memory result in differential patterns of IEG protein product expression in these two brain structures. Adult male Long-Evans rats were trained in either a hippocampal-dependent spatial water maze task, or a dorsal striatal-dependent cued water maze task. Ninety minutes after task acquisition, brains were removed and processed for immunocytochemical procedures, and the number of cells expressing Fos-like immunoreactivity (Fos-like-IR) and c-Jun-IR in sections from the dorsal hippocampus and the dorsal striatum were counted. In the dorsal hippocampus of rats trained in the spatial task, there were significantly more c-Jun-IR pyramidal cells in the CA1 and CA3 regions, relative to rats that had acquired the cued task, yoked controls (free-swim), or na?ve (home cage) rats. Relative to rats receiving cued task training and control conditions, increases in Fos-like IR were also observed in the CA1 region of rats trained in the spatial task. In rats that had acquired the cued task, patches of c-Jun-IR were observed in the posteroventral striatum; no such patches were evident in rats trained in the spatial task, yoked-control rats, or na?ve rats. The results demonstrate that IEG protein product expression is up-regulated in a task-dependent and brain structure-specific manner shortly after acquisition of cognitive and habit memory tasks.     

Book Reviews : Dane R. Gordon and David C. Durst (eds.), Civil Society in Southeast Europe,Rodopi, Amsterdam/New York, 2004.

Studies in East European Thought -     

Algorithmic complexity for psychology: a user-friendly implementation of the coding theorem method

Kolmogorov-Chaitin complexity has long been believed to be impossible to approximate when it comes to short sequences (e.g. of length 5-50). However, with the newly developed coding theorem method the complexity of strings of length 2-11 can now be numerically estimated. We present the theoretical basis of algorithmic complexity for short strings (ACSS) and describe an R-package providing functions based on ACSS that will cover psychologists’ needs and improve upon previous methods in three ways: (1) ACSS is now available not only for binary strings, but for strings based on up to 9 different symbols, (2) ACSS no longer requires time-consuming computing, and (3) a new approach based on ACSS gives access to an estimation of the complexity of strings of any length. Finally, three illustrative examples show how these tools can be applied to psychology.     

What is the impact of the explicit knowledge of sequence regularities on both deterministic and probabilistic serial reaction time task performance?

The aim of this study was to explore the role of prior explicit sequence knowledge by comparing its influence on serial reaction time (SRT) performance with either a deterministic or a probabilistic sequence. The results confirm that, with a deterministic sequence, preliminary explicit learning improves SRT performance. On the other hand, with a probabilistic sequence, the results show no advantage for SRT performance in explicit-learning conditions. In addition, by using the process dissociation procedure (Jacoby, 1991), we show that performance on a subsequent generation task was more sustained by controlled processes for participants in the explicit-learning conditions than for those in the incidental condition. On the whole, these results, showing that the influence of explicit knowledge can be suppressed in certain specific conditions, are consistent with the intervention of both implicit and explicit mechanisms in SRT tasks, and the results also show that their relative influence can be modulated by the particular demands of the task.     

The Relationships of Perceived Motivational Climate to Cohesion and Collective Efficacy in Elite Female Teams

The purpose of this study was to examine the relationships of perceived motivational climate to cohesion and collective efficacy in elite female teams. A total of 124 basketball and handball athletes completed two season measures (T1, T2). Relationships were examined at an individual level both statically and across time. Canonical correlations revealed that a combination of high perceptions of an ego-involving but low perceptions of a task-involving climate were associated with low perceptions of task cohesion at Time 1. High perceptions of a task-involving but low perceptions of an ego-involving climate were associated with higher perceptions of task cohesion and collective efficacy at Time 2. Moreover, low perceptions of an ego-involving and moderately low perceptions of a task-involving climate were associated with high perceptions of social cohesion at Time 2. Regression analyses including autoregressive influence indicated that a task-involving climate positively predicted variance in T2 group integration-task and collective efficacy after controlling for T1 scores. In contrast, an ego-involving climate negatively predicted changes in T2 athletes’ perceptions of social cohesion (individual attractions to the group-social [ATG-S], group integration-social [GI-S]) and group integration-task [GI-T] after controlling for T1 scores. Theoretical and practical implications are discussed.     

Decomposing animacy reversals between agents and experiencers: An ERP study

The present study aimed to refine current hypotheses regarding thematic reversal anomalies, which have been found to elicit either N400 or - more frequently - “semantic-P600” (sP600) effects. Our goal was to investigate whether distinct ERP profiles reflect aspectual-thematic differences between Agent-Subject Verbs (ASVs; e.g., ‘to eat’) and Experiencer-Subject Verbs (ESVs; e.g., ‘to love’) in English. Inanimate subject noun phrases created reversal anomalies on both ASV and ESV. Animacy-based prominence effects and semantic association were controlled to minimize their contribution to any ERP effects. An N400 was elicited by the target verb in the ESV but not the ASV anomalies, supporting the hypothesis of a distinctive aspectual-thematic structure between ESV and ASV. Moreover, the N400 finding for English ESV shows that, in contrast to previous claims, the presence versus absence of N400s for this kind of anomaly cannot be exclusively explained in terms of typological differences across languages.