An optimized facial stimuli paradigm for hybrid SSVEP+P300 brain computer interface

In this paper, hybrid BCI that merges Event Related Potentials (P300) and Steady State visual Evoked Potentials (SSVEP) simultaneously is proposed to enhance the performance of Four-choice command system. Here we integrate human facial structure in external visual stimulus to evoke stronger cortical responses in hybrid SSVEP+P300 BCI & compare it with non-face stimuli. We also addressed question of feasibility of eliciting one potential by face & other by non-face stimuli. To evoke SSVEP & P300 responses, paradigms with non-face stimuli, neutral face stimuli, and facial expression changes stimuli are proposed. We also projected additional paradigm where SSVEP is elicited by non-face and P300 by flashing different facial expressions. Results proved the last paradigm evoke stronger cortical potentials and thereby improve system accuracy and ITR than other paradigms. Author discussed external stimulus parameters that might affect simultaneous evocation of multiple brain potentials and their deterioration effect on individual potentials.     

Inner speech slips exhibit lexical bias, but not the phonemic similarity effect

Inner speech, that little voice that people often hear inside their heads while thinking, is a form of mental imagery. The properties of inner speech errors can be used to investigate the nature of inner speech, just as overt slips are informative about overt speech production. Overt slips tend to create words (lexical bias) and involve similar exchanging phonemes (phonemic similarity effect). We examined these effects in inner and overt speech via a tongue-twister recitation task. While lexical bias was present in both inner and overt speech errors, the phonemic similarity effect was evident only for overt errors, producing a significant overtness by similarity interaction. We propose that inner speech is impoverished at lower (featural) levels, but robust at higher (phonemic) levels.     

Biases towards internal features in infants' reasoning about objects

This paper reports the results of two sets of studies demonstrating 14-month-olds' tendency to associate an object's behavior with internal, rather than external features. In Experiment 1 infants were familiarized to two animated cats that each exhibited a different style of self-generated motion. Infants then saw a novel individual that had an internal feature (stomach color) similar to one cat, but an external feature (hat color) similar to the other. Infants looked reliably longer when the individual's motion was congruent with the hat than when it was congruent with the stomach. Using a converging method involving object choice, Experiment 2 found that infants prioritized the internal feature over the external feature only when the object's behavior was self-generated. In the absence of self-generated behaviors, however, infants did not show a preference towards the internal feature.     

注意和非注意条件下的整体和局部性质加工

以往关于整体和局部知觉的研究通常要求被试直接对出现在复合刺激整体或局部水平上的靶目标做反应,因此复合刺激与任务相关并被注意。该研究通过测量复合字母的整体和局部性质对随后出现的探测刺激的启动效应来研究在非注意条件下整体和局部性质加工的差异。实验一发现复合刺激的整体和局部性质对探测刺激产生负启动效应,但二者没有显著差异。实验二缩短了启动刺激与探测刺激之间的时间间隔,复合刺激的整体和局部性质对探测刺激都不再产生启动效应。在实验一、二中,当要求被试直接对复合刺激做反应时,其分辨局部性质的错误率都比分辨整体性质的错误率高。根据这些结果,讨论了在注意和非注意下的整体和局部性质加工的差异。     

儿童心理健康发展的家庭生态系统特点研究

通过元分析及变量频数分析技术完成影响儿童心理发展的家庭生态系统关键变量的筛选,运用生态系统发展观,对746名中小学生的家庭生态系统进行了研究。分别从差异模式、关系模式和系统结构模式对健康组和问题组儿童的家庭各子系统关键因素之间的差异,子系统关键因素间、子系统间的关系,以及整体生态系统的特点进行分析,考察了儿童心理健康发展的家庭生态系统特点。     

The alternative explanation to the alternative‐outcome effect and the detection of the focal outcome effect

Abstract: Previous studies on subjective probability judgment indicate that pair‐wise comparison between the focal and the strongest alternative outcome plays an important role in probability judgment. This study, however, found that the randomness of alternative outcomes affected probability judgment for focal outcome. In the present study, 182 participants provided probability estimates for winning on hypothetical slot machines where both successes and losses were composed of multiple outcomes. The randomness of both the focal and alternative outcomes were defined by the expression used in Rappoport and Budescu (1997 ). The analysis indicated that the more random the distributions of both focal and alternative outcomes, the higher the estimated probability for focal outcome. Some theoretical suggestions are discussed.     

大脑两半球与整体和局部性质的选择性加工

研究大脑两半球在加工整体和局部性质中的优势以及两半球能否同时分别选择两个复合刺激的整体和局部性质。实验中把一个复合字母随机呈现在左视野或右视野,或者把两个复合字母同时分别呈现在左视野和右视野。实验一发现,在单侧呈现条件下,被试检测左右视野的整体或局部靶目标的反应时没有显著差别,但在双侧同时呈现条件下,检测右视野局部靶目标比检测左视野局部靶目标时的反应时短。实验二要求被试检测同时呈现在左右视野的整体或局部靶目标,发现当两个视野的靶目标处于同一水平时(整体或局部)反应时较短,两个视野的靶目标处于不同水平时(一侧处于整体水平而另一侧处于局部水平)反应时较长。这些结果提示,当两个复合刺激同时呈现在左右视野时,大脑左半球在选择性加工局部性质时具有优势;左右两半球更容易选择两个复合刺激同一个水平的性质,分别选择两个复合刺激不同水平的性质比较困难。     

口语词语产生理论与语法特征通达研究的发展

近年来,研究者对口语词汇产生过程的各个层次展开了深入的探讨,各种理论与模型争论的焦点主要集中在各阶段间的关系、表征被选择的方式和词汇化的时间进程等方面,其中关于语法特征的通达一直是人们最为关注的问题之一。文章回顾了该领域内从研究初期至今较有代表性的一些理论、模型和有关语法特征通达的研究进展。希望能对有关汉语字词产生基本问题的研究有所推动。     

Global and local evaluations of public speaking performance in social anxiety

Differences in the relative use of global and local information (seeing the forest vs. the trees) may explain why people with social anxiety often do not benefit from corrective feedback, even though they pay close attention to details in social situations. In the current study, participants high (n = 43) or low (n = 47) in social anxiety symptoms gave a series of brief speeches, and then self-rated their speaking performance on items reflecting global and local performance indicators (self-assessment) and also received standardized performance feedback from an experimenter. Participants then completed a questionnaire asking how they thought the experimenter would rate their performance based on the feedback provided (experimenter assessment). Participants completed the self- and experimenter assessments again after 3 days, in addition to a measure of postevent processing (repetitive negative thinking) about their speech performance. Results showed that, as hypothesized, the High SA group rated their performance more negatively than the Low SA group. Moreover, the High SA group's ratings of global aspects of their performance became relatively more negative over time, compared to their ratings of local aspects and the Low SA group's ratings. As expected, postevent processing mediated the relationship between social anxiety group status and worsening global performance evaluations. These findings point to a pattern of progressively more negative global evaluations over time for persons high in social anxiety.