The interaction of objective and subjective organizations in a localization search task

We investigated how both objective and subjective organizations affect perceptual organization and how this perceptual organization, in turn, influences observers’ performance in a localization search task. Two groups of observers viewing exactly the same stimuli (objective organization) performed in significantly different ways, depending on how they were induced to parse the display (subjective organization). In Experiments 1 and 2, the observers were asked to describe the location of a tilted target among a varying number of vertical or horizontal distractors. Subjective organization was induced by instructing observers to parse the display into either three horizontal regions (rows) or three vertical regions (columns). The position of the target was critical: location performance, as assessed by reaction time and errors, was consistently impaired at the locations adjacent to the boundaries defining the regions, producing what we refer to as thesubjective boundary effect. Furthermore, the extent of this effect depended on whether the stimulus-driven and conceptually driven information concurred or conflicted. This made location information more or less accessible. In Experiment 1, the strength of objective grouping was a function of the proximity of the items (near or far conditions) and their orientation in a 6×6 matrix. In Experiment 2, the strength of objective grouping was a function of similarity of color (items were color coded by rows or by columns) and the orientation of the items in a 9×9 matrix. The subjective boundary effect was more pronounced when the display promoted grouping in the direction orthogonal to that of the task (e.g., when observers parsed by rows but vertical distractors were closer together [Experiment 1] or color coded [Experiment 2] to induce global columns). In contrast, this effect decreased when the direction of both objective and subjective organizations was parallel (e.g., when observers parsed by rows and horizontal distractors were closer together [Experiment 1] or were color coded [Experiment 2] to induce global rows). A localization search task proved to be an ideal forum in which objective and subjective organizations interacted. We discuss how these results indicated that observers’ performance in a localization task was determined by the interaction of objective and subjective organizations, and that the resulting perceptual organization constrained coarse location information.     

The relationship of gender,sex role,and law-and-order attitudes to nuclear opinions

Australian students' attitudes to nuclear weapons were considered in relation to sex-role identification and political orientations. By including a measure of sex-role orientation, we hoped to clarify earlier confusion surrounding gender as a predictor of nuclear views. Our hypothesis was that men and women with feminine sex-role orientations would display the strongest antinuclear feelings. Also, we predicted that an authoritarian political stance advocating strict law-and-order on the domestic front would predict support for nuclear weapons in international defense. The subjects were 46 male and 62 female first-year university students. The measure of nuclear attitudes was a 23-item inventory (NARQ) which had previously been extensively refined and validated for Australian populations (Jennings & Lawrence, 1986). The BSRI (Bem, 1974) measured sex-role orientation. An Australian law-and-order scale was also developed for this research. Latent trait models for rating data were applied to NARQ and law-and-order scales. The results revealed sex differences on approximately one-third of the nuclear opinion items, with men expressing stronger support for nuclear weapons in every case. Authoritarian law-and-order attitudes likewise predicted support for nuclear weapons in both men and women. A stepwise multiple regression analysis showed that BSRI masculinity and law-and order made separate, statistically significant, contributions to overall variation in nuclear views. These results were considered in relation both to previous research and to practical implications for political behavior.     

SINGLE-SEX VERSUS MIXED-SEX CLASSES AND GENDER SCHEMATA IN CHILDREN AND ADOLESCENTS

Positive effects for women and girls of all-female schools have been proposed, although there is relatively little clear empirical support for these beneficial results. Much of the cited research is based on elite all-female institutions or on parochial schools. This study takes advantage of the change of a private, nonparochial school from all girls to both sexes. Longitudinal data from grades 2 through 12 were collected over the course of the academic year to study the results of this transition. Stereotyping declined with age and over time in both types of class-rooms. Girls in single-sex classrooms showed some tendency to be more stereotyped in their perceptions of mixed-sex classrooms than did the girls who were actually in that setting. Thus, none of the measures showed any significant increase over time in stereotyping among girls in mixed-sex classes. Implications of these findings are discussed.     

Is the face-perception system human-specific at birth?

The present study investigates the human-specificity of the orienting system that allows neonates to look preferentially at faces. Three experiments were carried out to determine whether the face-perception system that is present at birth is broad enough to include both human and nonhuman primate faces. The results demonstrate that the newborns did not show any spontaneous visual preference for the human face when presented simultaneously with a monkey face that shared the same features, configuration, and low-level perceptual properties (Experiment 1). The newborns were, however, able to discriminate between the 2 faces belonging to the 2 different species (Experiment 2). In Experiment 3, the newborns were found to prefer looking at an upright, compared with an inverted, monkey face, as they do for human faces. Overall, the results demonstrate that newborns perceive monkey and human faces in a similar way. These findings are consistent with the hypothesis that the system underlying face preference at birth is broad enough to bias newborns' attention toward both human and nonhuman primate faces.     

Molecular and behavioral changes associated with adult hippocampus-specific SynGAP1 knockout

The synaptic Ras/Rap-GTPase-activating protein (SynGAP1) plays a unique role in regulating specific downstream intracellular events in response to N-methyl-D-aspartate receptor (NMDAR) activation. Constitutive heterozygous loss of SynGAP1 disrupts NMDAR-mediated physiological and behavioral processes, but the disruptions might be of developmental origin. Therefore, the precise role of SynGAP1 in the adult brain, including its relative functional significance within specific brain regions, remains unexplored. The present study constitutes the first attempt in achieving adult hippocampal-specific SynGAP1 knockout using the Cre/loxP approach. Here, we report that this manipulation led to a significant numerical increase in both small and large GluA1 and NR1 immunoreactive clusters, many of which were non-opposed to presynaptic terminals. In parallel, the observed marked decline in the amplitude of spontaneous excitatory currents (sEPSCs) and inter-event intervals supported the impression that SynGAP1 loss might facilitate the accumulation of extrasynaptic glutamatergic receptors. In addition, SynGAP1-mediated signaling appears to be critical for the proper integration and survival of newborn neurons. The manipulation impaired reversal learning in the probe test of the water maze and induced a delay-dependent impairment in spatial recognition memory. It did not significantly affect anxiety or reference memory acquisition but induced a substantial elevation in spontaneous locomotor activity in the open field test. Thus, the present study demonstrates the functional significance of SynGAP1 signaling in the adult brain by capturing several changes that are dependent on NMDAR and hippocampal integrity.     

Analysing user's reactions in advice-giving dialogues with a socially intelligent ECA

In this paper, we investigate the user's reactions to received suggestion by an Embodied Conversational Agent playing the role of artificial therapist in the healthy eating domain. Specifically, we analyse the behaviour of people who voluntarily requested to receive information from the agent, and we compare it with the results of a previous evaluation experiment in which subjects were not properly motivated to interact with the agent because they were selected for evaluating the system. This study is part of an ongoing research aimed at developing an intelligent virtual agent that applies natural argumentation techniques to persuade the users to improve their eating habits.     

Successes and failures in producing attentional object-based cueing effects

Over 30?years of research using Posner's spatial cueing paradigm has shown that selective attention operates on representations of spatial locations, leading to space-based theories of attention. Manipulations of stimuli and methods have shown this paradigm to be sensitive to several types of object-based representations-providing evidence for theories incorporating object-based attentional selection. This paper critically evaluates the evidence demanding object-based explanations that go beyond positing spatial representations alone, with an emphasis on identifying and interpreting successes and failures in obtaining object-based cueing effects. This overview of current evidence is used to generate hypotheses regarding critical factors in the emergence and influence of object representations-their generation, strength, and maintenance-in the modulation of object-based facilitatory and inhibitory cueing effects.