Visual perspective taking for avatars in a Simon task

In modern digital applications, users often interact with virtual representations of themselves or others, called avatars. We examined how these avatars and their perspectives influence stimulus–response compatibility in a Simon task. Participants responded to light/dark blue stimuli with left/right key presses in the presence of a task-irrelevant avatar. Changes in stimulus–response compatibility were used to quantify changes in the mental representation of the task and perspective taking toward this avatar. Experiments 1 and 2 showed that perspective taking for an avatar occurred in orthogonal stimulus–response mappings, causing a compatibility effect from the avatar’s point of view. In the following two experiments we introduced a larger variety of angular disparities between the participant and avatar. In Experiment 3, the Simon effect with lateralized stimulus positions remained largely unaffected by the avatar, pointing toward an absence of perspective taking. In Experiment 4, after avatar hand movements were added in order to strengthen the participants’ sense of agency over the avatar, a spatial compatibility effect from the avatar’s perspective was observed again, and hints of the selective use of perspective taking on a trial-by-trial basis were found. Overall, the results indicate that users can incorporate the perspective of an avatar into their mental representation of a situation, even when this perspective is unnecessary to complete a task, but that certain contextual requirements have to be met.     

Probing spatial working memory with the Corsi Blocks task

The Corsi Blocks task (CBT) measures spatial memory span, but methodological differences across previous studies prevent a clear appreciation of perceptual, memory, and motor contributions to spatial span. CBT performance in a standard condition was compared to performance with longer encoding intervals (3 vs 1 s), longer memory intervals (9 vs 1 s), or fewer response alternatives (all nine vs only the relevant positions). All experiments also contrasted ascending vs descending order of item difficulty and recorded response-initiation times. Performance improved with longer encoding and maintenance intervals and with fewer response alternatives. Item order had no reliable effects. Response-initiation times were a useful additional measure of spatial span. Implications of these findings for research using the CBT are discussed.     

Family, personality, and social risk factors impacting the retention rates of first-year Hispanic and Anglo college students

This study investigated familial and behavioral differences between Hispanic and Anglo-American first-year college students. Analyses of variance and chi-square analyses were used to test for ethnic differences in (a) risk factors associated with family dysfunction, family addictions, personality factors, and social experiences, (b) student problem behaviors, namely alcohol use, drug use, and eating disorders, (c) a one-year follow-up of student retention, and (d) specific factors related to retention at the one-year follow-up. The Hispanic freshmen appeared to demonstrate resilience despite a lack of mentoring and greater paternal addiction. However, the one-year follow-up suggested that Hispanic females were at particular risk for leaving school. To improve college retention rates, social policy should focus on Hispanic students' vulnerabilities and strengths in making important developmental transitions.     

Knowledge level learning and the power law: A soar model of skill acquisition in scheduling

Zusammenfassung. Das hier vorgestellte Modell lernt graduell, Planungsaufgaben aus der Klasse der Maschinenbelegungsprobleme (job-shop-scheduling problems) zu lösen. Mit Hilfe des Chunking-Mechanismus von Soar wird episodisches Wissen über die Belegungsreihenfolge von Aufträgen auf Maschinen memoriert. Bei der Entwicklung des Modells wurden zahlreiche qualitative (z. B. Transfereffekte) und quantitative Befunde (z. B. Bearbeitungszeiten) aus einer früheren empirischen Untersuchung berücksichtigt. In einer Validierungsstudie wurden dieselben Aufgaben von 14 Probanden und dem Modell bearbeitet. Die Passung von Simulationsdaten und empirischen Ergebnissen fiel insgesamt gut aus. Allerdings löst das Modell die Aufgaben schneller und zeigt auch einen etwas besseren Lernverlauf als die Probanden. Das Modell liefert eine Erklärung für das Rauschen, das typischerweise bei Bearbeitungszeiten zu beobachten ist: es handelt sich um erworbenes Wissen, das mehr oder weniger gut und auch unterschiedlich häufig auf neue Situationen übertragen wird. Der Lernverlauf der Probanden entspricht nur für aggregierte Daten einer Potenzfunktion (power law). Der vorgestellte Mechanismus zeigt, wie ein symbolisches Modell der Informationsverarbeitung graduelle Verhaltensänderungen generiert und wie der offensichtliche Erwerb allgemeiner Prozeduren ohne explizites Lernen von deklarativen Regeln erfolgen kann. Es wird nahegelegt, daß es sich hier um die Modellierung einer Form impliziten Lernens handelt. Summary. The model presented here gradually learns how to perform a job-shop scheduling task. It uses Soar's chunking mechanism to acquire episodic memories about the order to schedule jobs. The model was based on many qualitative (e.g., transfer effects) and quantitative (e.g., solution time) regularities found in previously collected data. The model was tested with new data where scheduling tasks were given to the model and to 14 subjects. The model generally fit these data with the restrictions that the model performs the task (in simulated time) faster than the subjects, and its performance improves somewhat more quickly than the subjects' performance. The model provides an explanation of the noise typically found in problem solving times - it is the result of learning actual pieces of knowledge that transfer more or less to new situations but rarely by an average amount. Only when the data are averaged (i.e., over subjects) does the smooth power law appear. This mechanism demonstrates how symbolic models can exhibit a gradual change in behavior and how the apparent acquisition of general procedures can be performed without resorting to explicit declarative rule generation. We suggest that this may represent a type of implicit learning.     

The puzzle of language evolution

Linguistics must again concentrate on the evolutionary nature of language, so that language models are more realistic with respect to human natural languages and have a greater explanatory force. Multi-agent systems are proposed as a possible route to develop such evolutionary models and an example is given of a concrete experiment in the origins and evolution of word-meaning based on a multi-agent approach.     

Memory for word locations in reading

Sentences were presented in various spatial formats, and readers localised one word of each sentence using a mouse cursor directly after reading. There was a localisation advantage for cumulative over single-word displays, for left-to-right presentation over presentation in a 3 x 3 grid, and for complete over incomplete sentences. Comparing performance for predictable and unpredictable word locations suggests that word location memory in reading decays within three seconds to a span of only 2-3 entries, and that readers can then reconstruct word locations from item memory. Implications for the role of spatial cognition in reading are discussed.     

Partner Preferences as a Function of Gender,Age, Political Orientation and Level of Education

An important current debate concerns the originof gender differences in partner preferences. Thesedifferences have been explained both in terms ofevolutionary theory and in terms of social role theory. The present study determines the relativestrengths of both perspectives by investigating, apartfrom gender, the influence of three other importantfactors on partner preferences and for which the two approaches offer divergent hypotheses: age,political orientation and level of education of therespondent. About 95% of the participants were WhiteDutch citizens, the rest were Dutch with one or twoparents from a different ethnic background.Participants were requested to write down the mostimportant characteristics of a potential partner(open-ended format), followed by an instruction toindicate the importance of 39 pre-selected characteristics. Resultsshow that men and women have highly similar preferencesfor characteristics in a potential partner. In addition,it is demonstrated that on crucial characteristics from an evolutionary perspective (i.e.,physical attractiveness and status) significantinteractions between age, political orientation, levelof education and/or gender of the respondents emerge.Most results offer support for a social role theoryof human mate selection. It is concluded that becausegender on its own merely explains a small proportion ofthe total variance in human mate selection, it is important to include other factors, not onlyin order to facilitate our understanding of the fullcomplexity of partner preferences, but also in order tomake theoretical progress in this area.