Perceptual completion and object-based representations in short-term visual memory

Object-based representations in visual short-term memory (VSTM) were examined using a change detection memory task. A display comprising two rows of four differently colored elements was followed by a probe display in which only one of the rows reappeared. On same trials, the probed row was identical to the corresponding row in the memory display. On different trials, two of the elements in the probed row had their colors exchanged. In each memory display, a task-irrelevant visual element appeared between the two rows, with the potential to function as an occluder. Performance was enhanced when perceptual completion meant that four, rather than eight, objects were perceived in the memory display and when the probe display revealed that the occluded elements continued behind the occluder. It appears that several forms of representation can co-occur to support VSTM, one of which is object based.     

What you get out of memory depends on the question you ask

Following study, participants received 2 tests. The 1st was a recognition test; the 2nd was designed to tap recollection. The objective was to examine performance on Test 1 conditional on Test 2 performance. In Experiment 1, contrary to process dissociation assumptions, exclusion errors better predicted subsequent recollection than did inclusion errors. In Experiments 2 and 3, with alternate questions posed on Test 2, words having high estimates of recollection with one question had high estimates of familiarity with the other question. Results supported the following: (a) the 2-test procedure has considerable potential for elucidating the relationship between recollection and familiarity; (b) there is substantial evidence for dependency between such processes when estimates are obtained using the process dissociation and remember-know procedures; and (c) order of information access appears to depend on the question posed to the memory system.     

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.     

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.     

Conjoint dissociations reveal involuntary "perceptual" priming from generating at study.

Incidental perceptual memory tests reveal priming when words are generated orally from a semantic cue at study, and this priming could reflect contamination by voluntary retrieval. We tested this hypothesis using a generate condition and two read conditions that differed in depth of processing (read-phonemic vs read-semantic). An intentional word-stem completion test showed an advantage for the read-semantic over the generate condition and an advantage for the generate over the read-phonemic condition, and completion times were longer than in a control test, prior to which there was no study phase. An incidental word-stem completion test showed equivalent priming for the read-semantic and read-phonemic study conditions, despite considerable power, and completion times were no longer than control, indicating that retrieval was involuntary, and insensitive to prior conceptual processing. The generate condition produced less priming than the read conditions, but significant priming nonetheless. The results show that priming from generating can be involuntary and suggest that lexical processes are responsible. They are also the first results conjointly showing a crossed double dissociation, a single dissociation, and a parallel effect across memory tests with identical physical retrieval cues.     

Top‐star’ priests and the catholic response to the ‘explosion’ of evangelical protestantism in brazil: The beginning of the end of the ‘walkout'?

Brazil's ‘new’ style of Catholicism, essentially the creation of a group of young, charismatic clergy—'pop‐star priests’ or ‘stars of the altar’, as they have become known—appears to have set in train a reversal, in that Latin American country at least, of the ‘walkout’ to evangelical Protestantism that David Martin analysed in Tongues of Fire: The Explosion of Pentecostalism in Latin America (1990). In that volume Martin described the rapid development of Protestantism in Latin America in the twentieth century and particularly from the 1960s as “... an explosion of conservative evangelical religion, a shift toward Pentecostalism, a rejection of ecumenism, and the manifestation among many of those involved of the evangelical capacity to unite modern technology with political conservatism”; (Martin, 1990: 54). During the past year millions of lapsed Catholics, and former Catholics some of whom were part of that ‘explosion’, have become involved in the ‘new’ Catholicism whose emergence illustrates the indispensable role of the media in religious reform and conversion in contemporary society. The article examines the superstructural elements of the ‘new’ Catholicism and compares its positive ‘cosmology’ and worldview with the emphasis on demonization in the teaching and ritual of the controversial, but highly successful evangelical Protestant Church, the Igreja Universal do Reino de Dens (the Universal Church of the Reign of God). This presentation also considers the various responses to the ‘new’ Catholicism which, although responsible for the return to worship of millions of Catholics, has been strongly criticised by both Liberation Theology and the more theologically and liturgically conservative wing within the Roman Catholic Church in Brazil.     

Institutional identity; sacramental potential: Catholic healthcare at century's end.

Government and market forces have fundamentally transformed the religious healthcare sector. Religious healthcare organizations are struggling to define their identities and determine what it is that makes them different and what implications the differences have for the delivery of social services and for public life. In response to these questions, the defenders of traditional Catholic healthcare make a variety of responses that first defend the continued relevance of the major institutions of Catholic healthcare, especially its hospitals, and second, specify reforms to make these institutions even more relevant to the new healthcare system. This essay argues that these defenses are inadequate to that challenge and that the reforms proposed are too timid. Catholic healthcare needs a better theoretical account of its mission and more creative institutional adaptations.