Representation of two geometric features of the environment in the domestic chick (<Emphasis Type="Italic">Gallus gallus</Emphasis>)

We report experiments based on a novel test in domestic chicks (Gallus gallus), designed to examine the encoding of two different geometric features of an enclosed environment: relative lengths of the walls and amplitude of the corners. Chicks were trained to search for a food reward located in one corner of a parallelogram-shaped enclosure. Between trials, chicks were passively disoriented and the enclosure was rotated, making reorientation possible only on the basis of the internal spatial structure of the enclosure. In order to reorient, chicks could rely on two sources of information: the relative lengths of the walls of the enclosure (associated to their left-right sense order) and the angles subtended by walls at corners. Chicks learned the task choosing equally often the reinforced corner and its rotational equivalent. Results of tests carried out in novel enclosures, the shapes of which were chosen ad hoc (1) to induce reorientation based only on the ratio of walls lengths plus sense (rectangular enclosure), or (2) to induce reorientation based only on corner angles (rhombus-shaped enclosure), suggested that chicks encoded both features of the environment. In a third test, in which chicks faced a conflict between these geometric features (mirror parallelogram-shaped enclosure), reorientation seemed to depend on the salience of corner angles. These results shed light on the elements of the environmental geometry which control spatial reorientation, and broaden the knowledge on the geometric representation of space in animals.     

A formal model for structuring local perceptions of environmental space

The problem of constructing computational models of space that mimic those found in human spatial reasoning is addressed. This paper extends a formal model that addressed point objects in a 2D world to include the presence of line objects and barriers. The problem consists of determining an appropriate global model for the spatial configuration given a sequence of local views or observations. A formal model is proposed based on constraint network theory. The model leads to the identification of stable regions within which perceptual information about the environment changes slowly, and zones of transition within which the perceptual information changes more quickly. A special case of transition zones is a gateway, which may be viewed as a kind of discontinuity or singularity in the model. It is expected that the model obtained will be used to mimic human mental representations of navigable outdoor environments.     

Narrating survival and change in Guatemala and South Africa: the politics of representation and a liberatory community psychology

Peace accords and international interventions have contributed to the suspension of armed conflict and the censuring of repressive regimes in many parts of the world. Some governments and their opposition parties have agreed to the establishment of commissions or other bodies designed to create historical records of the violations of human rights and foster conditions that facilitate reparatory and reconciliatory processes. This paper explores selected roles that community psychologists have played in this process of remembering the past and constructing new identities towards creating a more just future. With reference to two community groups (in Guatemala and South Africa) we show how efforts to speak out about one's own experiences of political and military repression involve complex representational politics that go beyond the simple binary opposition of silencing versus giving voice. The Guatemalan group consisted of Mayan Ixil women who, together with the first author, used participatory action research and the PhotoVoice technique to produce a book about their past and present struggles. The South African group, working within the ambit of the Truth and Reconciliation Commission and in collaboration with the third author and others, explored ways of speaking about their roles in apartheid and post-apartheid society. Although both these initiatives can be seen as moments in on-going struggles to overcome externally-imposed repressive practices that censor the voices of marginalized communities, they also serve to dispel overly romanticized notions of univocal communities now liberated to express themselves in an unmediated and unequivocal fashion. The paper discusses how each group of women instead entered into subtly nuanced relationships with community psychologists involving a continual interplay between the authenticity of their self-representational accounts and the requirements of the discursive technologies into which they were being inducted and the material conditions within their sites of struggle. In both cases the group's agenda also evolved over time, so that what emerged was not so much a particular account of themselves, or even the development of a particular voice for speaking about themselves, but an unfolding process—for the groups and for the community psychologists who accompanied them—of becoming active players in the postmodern, mediated world of self-representational politics and social struggle.     

Hostile attributional tendencies in maltreated children

The hostile attributional tendencies of maltreated children in elementary school across key relationship figures (i.e., parents, teachers, and peers), the relation between children's hostile attributional tendencies and the frequency and severity of maltreatment, and the role of children's hostile attributions of their parents in mediating the relation between maltreatment and children's hostile attributions of unfamiliar peers were examined. The sample consisted of 44 maltreated and 56 nonmaltreated children (females = 51) of mixed ethnicity. Subjects were administered a 20-item measure of attributional processes. The results indicated that relative to nonmaltreated children, physically abused boys were more likely to attribute hostile intentions to a variety of relationship figures, including their parents, an unfamiliar teacher, their best friend, and unfamiliar peers. A positive relation was also found between the frequency of physical abuse and hostile attributional tendencies among males. Finally, support was found for the role of children's hostile attributions of their mothers in mediating the relation between physical abuse and children's hostile attributions of unfamiliar peers. The results support a link between physical abuse and hostile attributional tendencies in children in early elementary school.     

The unification of mind: Integration of hemispheric semantic processing

Seventy-six participants performed a visual half-field lexical decision task at two different stimulus onset asynchronies (50 or 750 ms). Word targets were primed either by a highly associated word (e.g., CLEAN-DIRTY), a weakly associated word (e.g., CLEAN-TIDY), or an unrelated word (e.g., CLEAN-FAMILY) projected to either the same or opposite visual field (VF) as the target. In the short SOA, RVF-left hemisphere primes resulted in high associate priming regardless of target location (ipsilateral or contralateral to the prime) whereas LVF-right hemisphere primes produced both high and low associate priming across both target location conditions. In the long SOA condition, contralateral priming patterns converged, demonstrating only high associate priming in both VF locations. The results of this study demonstrate the critical role of interhemispheric transfer in semantic processing and indicate a need to elaborate current models of semantic processing.     

A Kripke Semantics for the Logic of Gelfand Quantales

Gelfand quantales are complete unital quantales with an involution, *, satisfying the property that for any element a, if a b a for all b, then a a* a = a. A Hilbert-style axiom system is given for a propositional logic, called Gelfand Logic, which is sound and complete with respect to Gelfand quantales. A Kripke semantics is presented for which the soundness and completeness of Gelfand logic is shown. The completeness theorem relies on a Stone style representation theorem for complete lattices. A Rasiowa/Sikorski style semantic tableau system is also presented with the property that if all branches of a tableau are closed, then the formula in question is a theorem of Gelfand Logic. An open branch in a completed tableaux guarantees the existence of an Kripke model in which the formula is not valid; hence it is not a theorem of Gelfand Logic.     

关联效应的实验研究

对汉语双字词的关联效应进行了实验研究,结果发现：语义关联效应显著,而语音关联效应则不存在。被试对各词再认判断确信程度和使用频率判断的模糊统计结果,在一定程度上验证了模糊痕迹理论的概括性表征、细节性表征和梗概抽取等观点,并在一定程度上验证了记忆归因理论。     

Contagion in the Representational Field of Water Recycling: Informing New Environment Practice Through Social Representation Theory

Water shortages in Australia have highlighted an urgent need for alternative water sources, and technologically, water recycling is argued to offer the most cost‐effective, environmentally sustainable solution to these shortages. Yet public support for its implementation is low even in the drought‐stricken areas of Australia. Drawing from the theory of social representations, this study addressed community perceptions of water recycling. Three interrelated methodologies were employed in a self‐report questionnaire. Individual difference scaling/multidimensional scaling analyses of three word association tasks revealed that the emergent social representation of water recycling was contradictory in affect. Normative responses indicated an awareness of the need to use recycled water whereas the functional responses were associated with a fear of contamination. An analysis of differential use scales further revealed that the perception of contagion was specific to when recycled water had contact with the body. The discursive analysis of respondents' comments expanded on both these findings. The study identified the themata of purity/impurity as underpinning the social understanding of water recycling. Copyright © 2011 John Wiley & Sons, Ltd.     

Effects of speed of word processing on semantic access: the case of bilingualism

Bilingual speakers generally manifest slower word recognition than monolinguals. We investigated the consequences of the word processing speed on semantic access in bilinguals. The paradigm involved a stream of English words and pseudowords presented in succession at a constant rate. English-Welsh bilinguals and English monolinguals were asked to count the number of letters in pseudowords and actively disregard words. They were not explicitly told that pairs of words in immediate succession were embedded and could either be semantically related or not. We expected that slower word processing in bilinguals would result in semantic access indexed by semantic priming. As expected, bilinguals showed significant semantic priming, indexed by an N400 modulation, whilst monolinguals did not. Moreover, bilinguals were slower in performing the task. The results suggest that bilinguals cannot discriminate between pseudowords and words without accessing semantic information whereas monolinguals can dismiss English words on the basis of subsemantic information.     

Neural correlates of audiovisual integration of semantic category information

Previous studies have found a late frontal-central audiovisual interaction during the time period about 150-220 ms post-stimulus. However, it is unclear to which process is this audiovisual interaction related: to processing of acoustical features or to classification of stimuli? To investigate this question, event-related potentials were recorded during a words-categorization task with stimuli presented in the auditory-visual modality. In the experiment, congruency of the visual and auditory stimuli was manipulated. Results showed that within the window of about 180-210 ms post-stimulus more positive values were elicited by category-congruent audiovisual stimuli than category-incongruent audiovisual stimuli. This indicates that the late frontal-central audiovisual interaction is related to audiovisual integration of semantic category information.