Visual recognition memory across contexts

In two experiments, we investigated the development of representational flexibility in visual recognition memory during infancy using the Visual Paired Comparison (VPC) task. In Experiment 1, 6- and 9-month-old infants exhibited recognition when familiarization and test occurred in the same room, but showed no evidence of recognition when familiarization and test occurred in different rooms. In contrast, 12- and 18-month-old infants exhibited recognition irrespective of testing room. Thus, flexibility across a change of room was observed at a younger age than flexibility across a change of background that has previously been seen with the VPC procedure (Robinson & Pascalis, 2004). To determine if limitations in representational flexibility across a change of background could be overcome by experiences during encoding, in Experiment 2, 6-, 9-, 12- and 18-month-old infants were familiarized with a picture on multiple backgrounds. At all ages, infants showed recognition across a change in background at test. These findings indicate that dissociating an item from its context during encoding may be an important factor in understanding the representational flexibility of visual recognition memory in infancy. Developmental changes in representational flexibility are likely driven by changes in the functional maturity of the hippocampal formation, and experience.     

Questioning implicit motor learning as instantiated by the pursuit-tracking task

The effect of concurrent visual feedback on the implicit learning of repeated segments in a task of pursuit tracking has been tested. Although this feedback makes it possible to regulate the positional error during the movement, it could also induce negative guidance effects. To test this hypothesis, a first set of participants (N=42) were assigned to two groups, which performed either the standard pursuit-tracking task based on the experimental paradigm of Pew ( 1974 ; group F-ST), or a task called "movement reproduction" in which the feedback was suppressed (group noF-ST). A second set of participants (N=26) performed in the same feedback condition groups but in a dual-task situation (F-DT and noF-DT; Experiment 2). The results appear to confirm our predictions since the participants in groups without feedback, contrary to those in groups with feedback, succeeded with practice in differentiating their performances as a function of the nature of the segments (repeated or nonrepeated) both in simple (Experiment 1) and in dual-task (Experiment 2) situations. These experiments indicate that the feedback in the pursuit-tracking task induces a guidance function potentially resulting in an easiness tracking that prevents the participants from learning the repetition.     

L’observance et certains de ses déterminants dans les maladies inflammatoires chroniques de l’intestin (MICI)

Factors that favor compliance are not constant in researches about IBD patients. The objective of this study is to determine, in a 79 compliant subjects sample, the links between factors themselves which influence observance: depression, alexithymia, causal attributions, health subjective quality of life, the relation with the physician, the health state evaluation and the rapport between therapeutic benefit/side effects (CGI). Results show that patients comprehend independently factors that motivate them to have treatment and seriousness of their health state. If the relationship established with the physician is perceived as fundamental, personal controllability does not seem essential in compliance. So, it seems important to consider more specifically the link between patient's perceived control and physician's perceived control of the disease.     

Development of a fully automated system for delivering odors in an MRI environment

We describe the development and evaluation of a computer-controlled system for delivering odors in a magnetic resonance imaging (MRI) environment. The system allows a timely presentation of different odors in synchrony with MRI sequences and participant’s inspiration phase. The rise/fall time of odor deliverance has been optimized to generate prompt and strong stimulations. Equipped with a user-friendly programming interface, the system can be used reliably in a wide range of experimental paradigms. We have paid particular attention to developing a portable system that is relatively easy, rapid, and inexpensive to replicate. The equipment has been tested in a 3-Tesla MRI in a boxcar paradigm, in which stimulation conditions alternated with rest periods (no stimulation). The experiment demonstrated the good functioning of the device and its efficiency in producing the expected activation in the olfactory cortex; it also revealed some methodological and technical aspects to be improved.     

The Psychosocial Vulnerability Model of Hostility as a Predictor of Coronary Heart Disease in Low-income African Americans

The current study examined social support and stress as mediators of the hostility—coronary heart disease (CHD) relationship as suggested by the psychosocial vulnerability model in a sample of low-income African Americans. Among 95 CHD patients and 30 healthy controls, hostility was negatively correlated with social support, but was not related to minor stress. CHD patients endorsed higher levels of hostility; however, the relationship between hostility and CHD status was diminished once stress and social support were included in the model. This study lends partial support for the psychosocial vulnerability model of hostility in African Americans, but suggests that the relationship between hostility and stress may be impacted by socioeconomic status.     

The influence of intergroup comparisons on Africans' intelligence test performance in a job selection context

Sub-Saharan Africans living in Belgium (N = 69) completed a culture-free intelligence test in a simulated job selection environment. Prior to testing, the authors instructed participants that Africans' average performance on this test was generally better (positive comparison), worse (negative comparison), or equal to Belgians' performance. In a control condition, no such information was given. Results indicated that, compared with the equal and control conditions, performance was lower when intergroup comparisons were negative. In the former condition, participants were also more likely to endorse external factors that may account for lower performance. The authors interpreted the findings in line with stereotype threat theory (C. M. Steele & J. Aronson, 1995). In the context of job selection, the validity of intelligence tests conducted with members of stigmatized groups may be affected by the salience of social stereotypes and intergroup social comparisons.     

发展性口吃的脑机制

口吃是一种常见的言语障碍,对此曾提出过大脑半球言语功能偏侧化异常假设。近期,发展性口吃的神经成像研究在支持这一经典假设的同时,还发现负责言语监控的颞叶系统和负责言语运动控制的额叶系统与皮层下脑结构存在功能失调,这可能损害言语产生时的精确时间控制。据此,研究者开始用神经网络的观点来解释发展性口吃产生的脑机制,认为患者可能存在由多个言语产生相关脑区构成的“双通路”网络的功能障碍     

刺激的知觉辨认难度与大脑两半球间的分布式加工

采用半视野速示术将标准刺激在中间视野呈现,比较刺激以不同偏心视角（3.5°,5°和6.5°）在左或右视野同时呈现,以检查不同偏心视角引起比较刺激知觉辨认难度的改变对汉字大写数字奇－偶概念同/异判断任务在大脑两半球间分布式加工的影响。结果显示：随偏心视角的增大正确反应时和错误百分数均显著提高;三种视角条件下左右手的正确反应时均有明显的右视野（左半球）优势;3.5°视角右视野（左半球）呈现时右手反应明显快于左手,5°视角右视野（左半球）与左视野（右半球）呈现时均为右手反应明显快于左手,6.5°视角右视野（左半球）与左视野（右半球）呈现时均为左手反应明显快于右手。这些结果提示：本研究条件下只有比较刺激在6.5°偏心视角呈现时刺激和反应可能出现大脑两半球间分布式加工,3.5°和5°视角呈现时可能为左半球单独加工。6.5°视角刺激呈现的分布加工明显由于大视角呈现时比较刺激辨认难度与注意要求的提高所致。     

Rhétorique et dialectique chez Aristote

Rhetoric and dialectic are two distinct circles, but in intersection. Rhetoric is an application (among others) of the dialectic to public debates. The dialectic is then the intellectual tool of rhetoric, distinct from its emotive means of persuading. But each of them can be antistrophos to the other one because both of them belong to the same sublunar world, our world. Such is Aristotle's answer, both to the sophists and to Plato.

     

CAN-4, an advanced author language for CAI,computer-based testing and psychological experimentation: PDP-9 implementation

The effective use of computers for tutorial (programmed instruction) teaching and on-line testing requires that curriculum authors have powerful special-purpose languages. One such language, CAN-4, has been designed and implemented to run on the PDP-9. The language includes advanced scoring, data recording, computation, timing, and file control facilities. The language and its implementation are described in relation to the instructional problems which the facilities are designed to meet.