无意视盲的认知神经机制

无意视盲现象是指即使某些刺激物出现在视野中, 观察者也并没有觉察到这些刺激物的存在。这种现象在我们的现实生活中普遍存在, 它是许多交通和医疗事故的罪魁祸首。回顾前人的研究结果我们发现, 从认知行为角度出发, 无意视盲主要由两方面原因引起, 即“资源有限”与“注意定势”。一般情况下, “资源有限”与“注意定势”会共同导致无意视盲; 但有时候, “注意定势”也会独立于“资源有限”直接导致无意视盲。另外, 从大脑神经机制的角度来看, “资源有限”与“注意定势”作用于大脑加工的中后期, 即使产生无意视盲, 意识加工脑区对非预期刺激也进行了一定的认知加工, 但是否能进入到意识层面, 一方面取决于刺激呈现后中期枕顶部位的意识输入, 另一方面取决于与刺激驱动相关的颞顶联合区的激活程度以及与记忆负荷相关的顶内沟的抑制程度。     

ERP signatures of conscious and unconscious word and letter perception in an inattentional blindness paradigm

A three-phase inattentional blindness paradigm was combined with ERPs. While participants performed a distracter task, line segments in the background formed words or consonant-strings. Nearly half of the participants failed to notice these word-forms and were deemed inattentionally blind. All participants noticed the word-forms in phase 2 of the experiment while they performed the same distracter task. In the final phase, participants performed a task on the word-forms. In all phases, including during inattentional blindness, word-forms elicited distinct ERPs during early latencies (∼200–280 ms) suggesting unconscious orthographic processing. A subsequent ERP (∼320–380 ms) similar to the visual awareness negativity appeared only when subjects were aware of the word-forms, regardless of the task. Finally, word-forms elicited a P3b (∼400–550 ms) only when these stimuli were task-relevant. These results are consistent with previous inattentional blindness studies and help distinguish brain activity associated with pre- and post-perceptual processing from correlates of conscious perception.     

Blindness and social trust: The effect of early visual deprivation on judgments of trustworthiness

Investigating the impact of early visual deprivation on evaluations related to social trust has received little attention to date. This is despite consistent evidence suggesting that early onset blindness may interfere with the normal development of social skills. In this study, we investigated whether early blindness affects judgments of trustworthiness regarding the actions of an agent, with trustworthiness representing the fundamental dimension in the social evaluation. Specifically, we compared performance between a group of early blind individuals with that of sighted controls in their evaluation of trustworthiness of an agent after hearing a pair of two positive or two negative social behaviors (impression formation). Participants then repeated the same evaluation following the presentation of a third (consistent or inconsistent) behavior regarding the same agent (impression updating). Overall, blind individuals tended to give similar evaluations compared to their sighted counterparts. However, they also valued positive behaviors significantly more than sighted controls when forming their impression of an agent’s trustworthiness. Moreover, when inconsistent information was provided, blind individuals were more prone to revise their initial evaluation compared to controls. These results suggest that early visual deprivation may have a dramatic effect on the evaluation of social factors such as trustworthiness.     

The role of similarity in inattentional blindness: Selective enhancement,selective suppression,or both?†

When people selectively pay attention to one set of objects and ignore another, unexpected stimuli often go unnoticed. Noticing rates are higher when the unexpected object matches the features of the attended items and lower when it matches those of the ignored items. No prior studies have fully disentangled these aspects of similarity; in previous work, the unexpected object fell on a continuum between the attended and ignored objects, so increasing the similarity to one set of objects necessarily decreased it to the other. We designed an inattentional blindness task in which we held similarity to the attended set constant and varied it with respect only to the ignored set, or vice versa. In Experiment 1, objects that were more similar to the attended set were noticed more often and objects that were more similar to the ignored set were noticed less often. Experiment 2, using a different set of unexpected objects, replicated the result that similarity to the ignored set affected noticing, but showed no effect of similarity to the attended set. In both experiments, the pattern of noticing rates differed for similarity with respect to the attended and ignored items, suggesting that suppression of ignored objects functions independently of enhancement of attended objects.     

重复知盲效应的理论之争及脑机制

重复知盲现象自被发现至今已走过四分之一世纪, 这期间重复知盲的产生机制一直是争论的焦点, 并有标记个体化理论、类型节点不应期理论、竞争理论、提取失败理论和建构/归因理论等多种理论解释。大量研究证明, 重复知盲是一种视知觉失败现象, 但也有研究认为它是一种记忆失败现象。很多研究还发现, 重复知盲不仅受到呈现时间和间隔刺激个数的限制, 还受到实验材料的性质、刺激的空间位置及人们的反应方式等多种因素的影响。近些年来, 随着ERP和fMRI等技术的利用, 从更深层次揭示了重复知盲产生的脑机制。同时, 重复知盲也作为一种实验范式应用于视觉加工领域的研究中。目前关于重复知盲仍然有很多问题值得探索。     

Déjà vu现象理论及其相关实验研究述评

Déjà vu指任何对目前体验的一种不适宜的熟悉感,并伴随着对过去体验的不确定感。对déjà vu的进一步深入研究将澄清对记忆的认识。首先,文章阐述了déjà vu现象产生的理论解释;其次,将相关的实验研究概括为：阈下知觉实验研究和阈上知觉实验研究。最后,讨论了目前déjà vu研究中所存在的一些问题。     

“White” or “European American”? Self-identifying labels influence majority group members' interethnic attitudes

Multiculturalism (i.e., the recognition and celebration of cultural differences) has many potential benefits for society, including reduced prejudice among nonminorities and increased psychological well-being among ethnic minorities. Yet nonminorities generally tend to resist multiculturalism more than do minorities and believe that it is irrelevant to them. Two studies were conducted to examine why and under what conditions this is the case. In both studies, nonminority participants were randomly assigned to mark their race/ethnicity as either “White” or “European American” on a demographic survey, before answering questions about their interethnic attitudes. Results demonstrated that nonminorities primed to think of themselves as White (versus European American) were subsequently less supportive of multiculturalism and more racially prejudiced, due to decreases in identification with ethnic minorities. Implications for how to improve nonminorities' attitudes toward multiculturalism are discussed.     

The contribution of category‐based and contextual suppression towards retrieval‐induced forgetting1

Abstract: This study examines whether both context‐related and category‐related memory impairment can be found using a retrieval‐induced forgetting procedure. One group of participants was tested using a standard retrieval‐practice paradigm, whereas for the no‐practice group the retrieval practice was replaced by irrelevant filler activity. The results showed that the within‐participant baseline items were recalled more poorly by the practice group than by the no‐practice group, whereas the practice group showed the standard retrieval‐induced forgetting effect. Thus, retrieval practice impaired recall for both within‐category and baseline items, although it impaired the former to a greater extent. This finding suggests that it is necessary to consider not only categorical relationships between items, but also context information shared by items when exploring retrieval‐induced forgetting.     

汉语句子加工中RB效应的研究

本研究采用完整,不完整和同形异义句作为实验材料考察了汉语句子加工中的RB效应。研究发现:(1)在汉语句子加工中,完整句和不完整句中均存在RB效应,且完整句的RB效应要强于不完整句。造成这种强度上不一致的主要原因是由于不完整句的RB效应导致句法和语义被破坏,并对R2有较高的侵犯性;(2)在同形异义字的汉语句子加工中,也存在RB效应,其结果与重复句一致。它表明同形异义字不影响RB效应的强弱或有无。以上结果表明,由于RB效应对语境的作用不敏感,因此,RB效应应出现在语义加工之前的阶段。     

Suppression history of distractor location biases attentional and oculomotor control

Past selection experience greatly affects the deployment of attention such that targets are more readily selected if their features or locations were more frequently selected in the past. Crucially, recent studies have shown similar experience-dependent effects also for salient task irrelevant stimuli: distractors exerted less interference if they appeared at a location where they were presented more often, relatively to other possible locations. Here we investigated the effects of such suppression history on the immediate behavioural correlates of attentional deployment, i.e., eye movements. Participants were to make saccadic eye movements to a target stimulus, while ignoring a highly distracting irrelevant visual onset appearing abruptly on the screen in a proportion of trials. Crucially, this irrelevant onset occurred more frequently in two locations on the visual display and our results showed that, relatively to distractors elsewhere, onsets presented at these locations became easier to ignore, giving rise to reduced oculomotor capture. Consistent with the notion that experience can alter attentional deployment towards spatial locations, these findings indicate that, through learning, the priority of high frequency locations becomes suppressed, attenuating the intrinsic saliency of distractors appearing therein. Traces left by individual events of attentional suppression decrease the processing priority of coordinates within topographic maps of the visual space.