Enhancing the mental representations of space used by blind pedestrians, based on an image schemata model

The configuration of mental representation of space plays a major role in successful navigational activities. Therefore, navigational assistance for pedestrians who are blind should help them to better configure their mental representation of the environment. In this paper, we propose and exploit a computational model for the mental representation of urban areas as an aid to orientation and navigation for visually impaired pedestrians. Our model uses image schemata to capture the spatial semantics and configural elements of urban space necessary for this purpose. These image schemata are schematic structures that are continually requested by individuals in their perception, bodily movement and interaction with surrounding objects. Our proposed model also incorporates a hierarchical structure to provide different levels of detail tied to appropriate spatial perspectives at each scale. We presume that such computational model will help us to develop an appropriate structure of spatial data used to assist the target population. At the end of the paper, we illustrate the utility of our configural model by developing a typical scenario for the navigation of a blind pedestrian in an urban area.     

Source-monitoring training facilitates preschoolers' eyewitness memory performance

Preschool children are more susceptible to misleading postevent information than are older children and adults. One reason for young children's suggestibility is their failure to monitor the source of their memories, as in, for example, discriminating whether an event was seen live versus on television. The authors investigated whether source-monitoring training would decrease preschoolers' suggestibility. Thirty-six 3-4-year-olds observed target live and video events and were then given source-monitoring or recognition (control) training on nontarget events. Following training, all children answered 24 misleading and nonmisleading target-event questions. Children given source-monitoring training were more accurate than control group children in response to misleading and nonmisleading yes-no questions and in response to nonmisleading, open-ended questions. Implications for strategy development, dual representation, and child witness interviewing are discussed.     

PERPETUAL FOREIGNER IN ONE'S OWN LAND: POTENTIAL IMPLICATIONS FOR IDENTITY AND PSYCHOLOGICAL ADJUSTMENT

The perpetual foreigner stereotype posits that members of ethnic minorities will always be seen as the "other" in the White Anglo-Saxon dominant society of the United States (Devos & Banaji, 2005), which may have negative implications for them. The goal of the present research was to determine whether awareness of this perpetual foreigner stereotype predicts identity and psychological adjustment. We conducted a series of studies with 231 Asian Americans and 211 Latino/as (Study 1), 89 African Americans (Study 2), and 56 Asian Americans and 165 Latino/as (Study 3). All participants completed measures of perceived discrimination, awareness of the perpetual foreigner stereotype, conflict between ethnic and national identities, sense of belonging to American culture, and demographics. In Study 3, participants also completed measures of psychological adjustment: depression, hope, and life satisfaction. All participants were students at a large, public university on the West Coast of the United States. Across studies, we found that even after controlling for perceived discrimination, awareness of the perpetual foreigner stereotype was a significant predictor of identity conflict and lower sense of belonging to American culture. From Study 3, we also found that, above and beyond perceived discrimination, awareness of the perpetual foreigner stereotype significantly predicted lower hope and life satisfaction for Asian Americans, and that it was a marginal predictor of greater depression for Latino/as. These results suggest that the perpetual foreigner stereotype may play a role in ethnic minority identity and adjustment.     

Boundaries of American Identity: Relations Between Ethnic Group Prototypicality and Policy Attitudes

We sought to document that the extent to which different ethnic groups are perceived as embodying the American identity is more strongly linked to antiminority policy attitudes and acculturation ideologies among majority‐group members (European Americans) than among minority‐group members (Asian Americans or Latino/as). Participants rated 13 attributes of the American identity as they pertain to different ethnic groups and reported their endorsement of policy attitudes and acculturation ideologies. We found a relative consensus across ethnic groups regarding defining components of the American identity. However, European Americans were perceived as more prototypical of this American identity than ethnic minorities, especially by European American raters. Moreover, for European Americans but not for ethnic minorities, relative ingroup prototypicality was related to antiminority policy attitudes and acculturation ideologies. These findings suggest that for European Americans, perceptions of ethnic group prototypicality fulfill an instrumental function linked to preserving their group interests and limiting the rights afforded to ethnic minorities.     

Informed horses are influential in group movements,but they may avoid leading

In species that move in cohesive groups, animals generally reach decisions through socially distributed processes, and individual knowledge is expected to influence collective decision making. Pooling of information should not be considered a general rule, however, since conflicts of interest may occur between group members. When resources are limited or highly attractive, higher-ranking individuals can prevent others from accessing food, and subordinates may have an interest in withholding information about its location. We investigated the role individual knowledge may play in recruitment processes in four groups of horses (Equus caballus). Animals were repeatedly released in a food search situation, in which one individual had been informed about the location of a preferred food, while another was a naïve control subject. Horses that were informed about the location of the feeding site were seen to approach the food source more steadily and were followed by a higher number of group members than their uninformed counterparts. Recruitment processes appeared mostly passive. Among the informed subjects, lower-ranking individuals were overall less followed than the higher-ranking ones. Most lower-ranking horses arrived alone at the feeding site. Non-followed informed subjects spent less time in active walk and used direct paths less frequently than followed animals, and they were joined by fewer partners at the attractive food source and spent more time feeding alone. This indicates that the influence of informed individuals on the behavior of other group members was a mixed process. Some horses brought nutritional benefits to their conspecifics by leading them to food supplies, whereas the behavior of others might be functionally deceptive.     

Sequent Calculi and Decision Procedures for Weak Modal Systems

We investigate sequent calculi for the weak modal (propositional) system reduced to the equivalence rule and extensions of it up to the full Kripke system containing monotonicity, conjunction and necessitation rules. The calculi have cut elimination and we concentrate on the inversion of rules to give in each case an effective procedure which for every sequent either furnishes a proof or a finite countermodel of it. Applications to the cardinality of countermodels, the inversion of rules and the derivability of Löb rules are given.     

Unfamiliar voice discrimination for short stimuli in newborns

In order to determine the minimal information required for newborns to discriminate unfamiliar voices two experiments were performed using the presentation of single disyllabic words uttered by male and female speakers. In the first experiment, utilizing the standard high‐amplitude‐sucking procedure, no significant discrimination was obtained. Hypothesizing that this failure in discrimination could be due to a deficient attention at the unique moment of stimulus change, a second experiment was performed in which the same to‐be‐discriminated stimuli alternated every minute and in which multiple tokens of the same word were presented to increase stimulus variability. Evidence for voice discrimination was obtained, suggesting that newborns are able to characterize unfamiliar voices on the basis of restrained vocal‐tract related information and minor prosodic information. Remarks addressing the consequences of stimulus organization upon attentional demands in experimental procedures in young infants are also presented.     

The susceptibility of young preschoolers to source similarity effects: Confusing story or video events with reality

This study examined children’s tendency to confuse events that varied in source similarity, which was manipulated using different media of event presentation. In Experiment 1, children in two age groups (3- and 4-year-olds and 5- and 6-year-olds) experienced a live presentation of an event, and another event was either heard from a story (low similarity group) or seen on a video (high similarity group). Immediately afterward, the children were asked to monitor the source of the events. The children in the low similarity group produced higher source discrimination scores than did the children in the high similarity group. Overall, the older children were better at source monitoring than were the younger children. In Experiment 2, the procedure was replicated except that the children’s source monitoring was tested after a 4-day delay. When attributing the source of the story or video events, both 3- and 4-year-olds and 5- and 6-year-olds in the low similarity group produced more accurate story or video attributions than did their age mates in the high similarity group. However, when attributing the source of the live events, only the 3- and 4-year-olds evidenced this effect of source similarity. The 5- and 6-year-olds in both the low and high similarity groups performed at ceiling levels for live discriminations.