Electrophysiological analysis of stimulus variables in equivalence relations

Recently, electrophysiological measures have been used to evaluate the functional overlap between semantic relations and laboratory-defined equivalence relations with abstract stimuli. Several studies using semantic judgment procedures have shown that accompanying EEG-measured neural activity for stimulus pairs from equivalence classes is very similar to that of word pairs from participants' native language. However, those studies often included pronounceable elements (e.g., written nonsense syllables) as at least one member of the experimentally defined classes. The present study conducted EEG studies that contrasted classes with and without such elements. Two groups of undergraduate students completed a matching-to-sample procedure to establish 3 4-member equivalence classes. For Group 1, samples and comparisons were pronounceable pseudowords and abstract figures. For Group 2, the matching-to-sample stimuli were abstract figures only. EEG data recorded during the semantic judgment tasks showed waveform patterns compatible with prior studies of semantic relations in Group 1 but not in Group 2.     

词汇加工初期语义属性的激活程度:来自ERP的证据

运用事件相关脑电位（ERP）技术,采用快速掩蔽启动范式和Go/Nogo范式,探讨汉语重复启动和语义相关启动中语义激活程度的差异和特点。实验中要求被试执行一个额外的语义判断任务,对关键刺激不做明显的行为反应。结果发现,在重复启动条件下获得了稳定的N400效应,语义相关启动条件下没有N400效应;重复启动和语义相关启动条件均未产生N250效应。在较短的SOA条件下,词频对语义的激活和加工不产生影响。     

ELECTROPHYSIOLOGICAL CORRELATES OF STIMULUS EQUIVALENCE PROCESSES

Research reported here concerns neural processes relating to stimulus equivalence class formation. In Experiment 1, two types of word pairs were presented successively to normally capable adults. In one type, the words had related usage in English (e.g., uncle, aunt). In the other, the two words were not typically related in their usage (e.g., wrist, corn). For pairs of both types, event‐related cortical potentials were recorded during and immediately after the presentation of the second word. The obtained waveforms differentiated these two types of pairs. For the unrelated pairs, the waveforms were significantly more negative about 400 ms after the second word was presented, thus replicating the “N400” phenomenon of the cognitive neuroscience literature. In addition, there was a strong positive‐tending wave form difference post‐stimulus presentation (peaked at about 500 ms) that also differentiated the unrelated from related stimulus pairs. In Experiment 2, the procedures were extended to study arbitrary stimulus—stimulus relations established via matching‐to‐sample training. Participants were experimentally näive adults. Sample stimuli (Set A) were trigrams, and comparison stimuli (Sets B, C, D, E, and F) were nonrepresentative forms. Behavioral tests evaluated potentially emergent equivalence relations (i.e., BD, DF, CE, etc.). All participants exhibited classes consistent with the arbitrary matching training. They were also exposed also to an event‐related potential procedure like that used in Experiment 1. Some received the ERP procedure before equivalence tests and some after. Only those participants who received ERP procedures after equivalence tests exhibited robust N400 differentiation initially. The positivity observed in Experiment 1 was absent for all participants. These results support speculations that equivalence tests may provide contextual support for the formation of equivalence classes including those that emerge gradually during testing.     

身体清洁启动后道德纯洁词加工的时间特征:来自ERPs的证据*

采用事件相关电位技术和语义启动范式,考察身体清洁刺激启动后对道德纯洁词加工的影响及其内在神经机制,探讨身体清洁信息与道德纯洁信息的认知加工特征。研究通过启动词(清洁词VS非清洁词)与目标词(道德纯洁词VS非词)四类刺激类型在N400波幅和潜伏期上有无差异来进行判断。结果发现,启动词(清洁词VS非清洁词)与目标词(道德纯洁词VS非词)四类刺激类型所诱发的N400成分差异显著,与非清洁词-道德纯洁词相比,清洁词-道德纯洁词所诱发了更小的N400波幅。结果表明:身体清洁词与道德纯洁词之间存在紧密的语义联结。身体清洁词启动后,个体更关注道德纯洁信息。     

The merger and development of equivalence classes by unreinforced conditional selection of comparison stimuli

Three experiments assessed the likelihood that subjects with histories of equivalence class development would respond conditionally on new discriminations in the absence of differential consequences for responses. In the first two experiments, two groups of subjects with different experimental histories, but whose performances showed four equivalence classes, responded on trials without explicit reinforcement involving samples from two of the classes and comparisons from the other two classes, in a two-choice matching-to-sample format. Subjects consistently selected a particular comparison in the presence of a particular sample. Subsequent tests showed the emergence of equivalence relations between stimuli from classes linked by the unreinforced conditional selections. Subsequently, in Experiment II, the subjects' responses in the conditional selection trials were reinforced if the selection was reversed from that made previously. Although reversed selection was maintained, 2 of the 3 subjects continued to perform on equivalence relation trials according to their original unreinforced selections. In the third experiment, these 2 subjects responded on a series of conditional discriminations involving three new pairs of sample stimuli and one new pair of comparison stimuli. No explicit reinforcement followed responses on any trial in this experiment. Subsequent tests for equivalence between sample stimuli revealed the development of two equivalence classes.     

音乐意义传递的神经证据——基于启动范式的发现与思考

使用语义启动(semantic priming)、概念启动(conceptual priming)、情感启动(affective priming)以及和声启动(harmonic priming)四种启动范式及其变式,认知神经科学的研究证实:音乐能够传递不同的意义,其主要的神经证据是两大脑电指标:对应于外在音乐意义(extra-musical meaning)的N400与对应于内在音乐意义(intra-musical meaning)的N5。对4种启动范式的分析发现:1)音乐以"语义"与"非语义"两种形式为媒介传递意义;2)启动范式的核心特征即是对基于"音乐知觉与图式"的"期望匹配与不匹配效应"的操作。与此同时,近期的研究表明N400与N5间的关系并非完全的"彼此独立",而是倾向于共存与共变,甚至是一个成分的两种表达。未来研究在进一步厘清音乐内、外在意义深层关联的同时,有必要将音乐意义传递的神经科学研究纳入到更为宏阔的时代、地域与社会性背景之中。     

The transfer of specific and general consequential functions through simple and conditional equivalence relations

The purpose of this study was to examine the transfer of consequential (reinforcement and punishment) functions through equivalence relations. In Experiment 1, 9 subjects acquired three three-member equivalence classes through matching-to-sample training using arbitrary visual forms. Comparison stimuli were then given conditioned reinforcement or punishment functions by pairing them with verbal feedback during a sorting task. For 8 of the 9 subjects, trained consequential functions transferred through their respective equivalence classes without additional training. In Experiment 2, transfer of function was initially tested before equivalence testing per se. Three of 4 subjects showed the transfer without a formal equivalence test. In Experiment 3, 3 subjects were given training that gave rise to six new three-member conditional equivalence classes. For 2 of the subjects, the same stimulus could have either a reinforcement or punishment function on the basis of contextual cues that defined its class membership. Experiment 4 assessed whether equivalence training had established general or specific consequential functions primarily by adding novel stimuli in the transfer test. Subjects treated even novel feedback stimuli in the transfer test as consequences, but the direction of consequential effects depended upon the transfer of specific consequential functions through equivalence relations.     

汉英语言内及语言间重复启动效应的ERP研究

16名母语为汉语的被试参加了一个混合语言的语义判断任务,关键词用汉语和英语呈现,然后重复这些词（语言内或者语言间）。比较词汇第一次呈现、语言内和语言间重复产生的N400波幅的差异发现：汉语和英语的语言内重复启动效应差异不显著,而两种方向的语言间重复启动效应存在不对称性,从英语到汉语的重复启动效应显著大于从汉语到英语的重复启动效应,这与双语表征的非对称模型不尽一致。     

Modulating younger and older adults’ performance in ignoring pictorial information during a word matching task

Using both behavioural and event-related potential (ERP) data, the current study sought to examine the neurophysiological underpinnings for the effect of distracting pictorial information on semantic word matching performance in younger and older adults. This was tested in the context of semantic relations between task-relevant word pairs, a task-irrelevant picture and the resultant N400 differences in ERP. Younger and older adults were shown a context word superimposed on a to-be-ignored picture, followed by a test word. Their task was to determine whether the prime and test words were semantically related. The to-be-ignored pictures were interfering (for ‘No’ trials), facilitating (for ‘Yes’ trials), or neutral (for both ‘Yes’ and ‘No’ trials) to the expected responses. The interfering and facilitatory effects of to-be-ignored pictures were assessed under more automatic and more controlled conditions by manipulating the context–test interstimulus-interval (ISI) as 50 ms and 1000 ms, respectively. The analysis of the N400 at centro-parietal sites during test word display revealed similar N400 amplitudes for the ‘No’ response trials at the two ISIs, suggesting that younger and older adults showed an equivalent effect from interfering pictures. In contrast, younger adults showed greater reductions in the N400, as compared to older adults, for ‘Yes’ trials indicating differential effects in facilitation from to-be-ignored pictorial information, but only in the long ISI condition. The data are discussed in terms of age differences in resource demanding strategy use during a semantic word matching task, specifically during controlled retrieval.     

汉字识别中字形畸变和语境的ERP效应

以事件相关电位（ERP）技术和语义启动范式,采用同一字判断（靶字延迟反应）作业,考察字形畸变和语境对低频汉字识别的影响。结果发现,无语义启动时,畸变靶字正确率低于清晰靶字;启动效应只体现在畸变时的正确率上。150–300ms窗口,畸变字比清晰字诱发峰值更负的N170;300–500ms时间窗口,不启动条件诱发平均波幅更负的N400,畸变字诱发更大N400。结论是,畸变字诱发的N170成分,在一定程度上反映了字形加工;N400的语义启动效应和畸变效应,扩展Holcomb的研究,并支持语义提取理论。     

Right Hemisphere Activation during Indirect Semantic Priming: Evidence from Event-Related Potentials

Healthy subjects performed a lexical decision task in a semantic priming paradigm while event-related potentials (ERPs) were recorded from 64 channels. Semantic distance between prime and target was varied by including directly, indirectly, and nonrelated word pairs. At centro-parietal electrodes an N400 to nonrelated pairs was elicited bilaterally which was sensitive only to direct, but not to indirect semantic priming. These N400 priming effects were mirrored by the RT data. At inferior fronto-temporal sites directly related words showed ERP priming effects over both hemispheres. However, indirectly related words only elicited ERP priming effects over the right hemisphere. These results support the hypothesis that the right hemisphere semantic system is involved in processing of remote semantic information.     

A transfer of self-discrimination response functions through equivalence relations

The present study tested the idea that human self-discrimination response functions may transfer through equivalence relations. Four subjects were trained in six symbolic matching-to-sample tasks (if see A1, choose B1; A1-C1, A2-B2, A2-C2, A3-B3, A3-C3) and were then tested for the formation of three equivalence relations (B1-C1, B2-C2, B3-C3). Two of the B stimuli (B1 and B2) were then used to train two different self-discrimination responses using either detailed instructions (Subjects 1 to 3) or minimal instructions (Subject 4) on two complex schedules of reinforcement (i.e., subjects were trained to pick the B1 stimulus if they had not emitted a response, and to pick the B2 stimulus if they had emitted one or more responses on the previous schedule). All 4 subjects showed the predicted transfer of self-discrimination response functions through equivalence relations (i.e., no response on the schedule, pick C1; one or more responses on the schedule, pick C2). Subjects also demonstrated this transfer when they were required to discriminate their schedule performance before exposure to the schedule (i.e., “what I intend to do”). Four control subjects were also used in the study. Two of these (Subjects 5 and 6) were not exposed to any form of matching-to-sample training and testing (nonequivalence controls). The 2 remaining subjects (7 and 8) were exposed to matching-to-sample training and testing that incorporated stimuli not used during the transfer test; C1 and C2 were replaced by N1 and N2 during the matching-to-sample training and testing, but C1 and C2 were used for the transfer tests (equivalence controls). All 4 subjects failed to produce the self-discrimination transfer performances observed with the experimental subjects.     

Modulating younger and older adults’ performance in ignoring pictorial information during a word matching task

Using both behavioural and event-related potential (ERP) data, the current study sought to examine the neurophysiological underpinnings for the effect of distracting pictorial information on semantic word matching performance in younger and older adults. This was tested in the context of semantic relations between task-relevant word pairs, a task-irrelevant picture and the resultant N400 differences in ERP. Younger and older adults were shown a context word superimposed on a to-be-ignored picture, followed by a test word. Their task was to determine whether the prime and test words were semantically related. The to-be-ignored pictures were interfering (for ‘No’ trials), facilitating (for ‘Yes’ trials), or neutral (for both ‘Yes’ and ‘No’ trials) to the expected responses. The interfering and facilitatory effects of to-be-ignored pictures were assessed under more automatic and more controlled conditions by manipulating the context–test interstimulus-interval (ISI) as 50 ms and 1000 ms, respectively. The analysis of the N400 at centro-parietal sites during test word display revealed similar N400 amplitudes for the ‘No’ response trials at the two ISIs, suggesting that younger and older adults showed an equivalent effect from interfering pictures. In contrast, younger adults showed greater reductions in the N400, as compared to older adults, for ‘Yes’ trials indicating differential effects in facilitation from to-be-ignored pictorial information, but only in the long ISI condition. The data are discussed in terms of age differences in resource demanding strategy use during a semantic word matching task, specifically during controlled retrieval.     

Effect of observing response requirements to sample and comparison stimuli on the establishment of reject control (sample/S- relations)

The establishment of sample/S- relations (or reject control) during conditional discrimination training (AB, BC) affects transitivity (AC), equivalence (CA) and reflexivity (AA, BB, CC) test outcomes. The present study parametrically evaluated the effects of different observing patterns to comparison stimuli on the establishment of reject control during baseline conditional relation training. A matching-to-sample with observing requirements (MTS-OR) procedure was implemented during AB and BC conditional discrimination training. During training, the participants were required to observe the sample and incorrect comparison on every trial before responding. In addition, the participants were divided into three groups that differed regarding the percentage of training trials on which they were prevented from observing the correct comparison stimuli: 25%, 50%, and 75%. Once the mastery criteria were achieved during training, transitivity (AC), symmetry (BA, CB), equivalence (CA), and reflexivity (AA, BB, CC) tests were conducted with all comparison stimuli visible from the beginning. The results suggest that the number of errors during transitivity, equivalence, and reflexivity tests progressively increased as participants were prevented from observing the correct comparison on a greater number of trials during training. Symmetry test results, however, were not affected by the experimental manipulation. Moreover, the number of participants showing reject-control patterns during tests slightly increased and the number of participants showing select-control patterns decreased as a function of the number of trials on which the participants were prevented from observing the correct comparison. Thus, we suggest that observing patterns during training is a relevant variable that affects equivalence test outcomes.     

音乐对情感词加工的情感/意义双启动效应

本研究在前人研究的基础上进一步探讨音乐对情感词的启动机制。采用内隐情感启动范式,运用脑电技术考察多种情感类型的音乐片段对情感意义一致或不一致的词加工的启动影响。行为实验结果显示,音乐对情感词产生启动效应。脑电实验的结果发现,音乐对情感词的启动效应表现为早晚两个子成分的N400效应,首先是音乐直接引发的情绪产生第一个启动,表现为早成分的N400;其次是音乐通过联想引发的情感语义而产生第二个启动,表现为晚成分的N400。据此可以认为,音乐对情感词的启动是双启动模式。     

Stereotype activation is unintentional: Behavioural and event‐related potenials evidence

In this study, a priming Stroop paradigm was used to determine whether stereotype activation is unintentional. Priming conditions (priming/no‐priming) and the relationship between priming and target (consistent/inconsistent/no‐relation) were the independent variables; accuracy, reaction time and N400 amplitude were used as dependent variables. The reaction time revealed that stereotype activation is, to some extent, unintentional. Furthermore, the event‐related potenial (ERP) results showed that N400 amplitude was larger for inconsistent conditions than for consistent conditions. This result supported the notion that stereotype activation is an unintentional and automatic process.     

高度模糊靶字下的N400语义启动效应：词汇加工理论的证据

本研究基于不可识别模糊字词仍能诱发N400的词汇加工理论的假设,让被试对模糊字进行同一字延迟判断,利用脑电技术记录不同模糊程度靶字的认知过程,来探讨N400出现的条件,以阐明N400反映的是词汇加工,还是词汇后加工。实验结果表明：与可识别、轻度模糊汉字一样,不可识别、高度模糊汉字仍然可以诱发N400;这种N400语义启动效应反映了词汇加工过程。     

汉字模糊度、字频和语义启动在N400上的交互作用：N400的IA模型的证据

通过两个实验, 采用事件相关电位技术, 记录大学生被试在同一字判断任务中的脑电波形。两个实验涉及三个因素, 包括模糊度、字频和语义, 语义和字频为被试内设计, 以启动字-靶字(模糊)-探测字的呈现序列为一个测试(trial), 要求被试判断靶字和探测字是否是同一个字。两个实验除了靶字的模糊度不同外, 其他材料完全相同。结果发现, 实验1字频和语义启动间存在交互作用, 其中低频条件下无语义启动比语义启动的N400波幅更偏负, 高频条件则无这种差异; 实验2中只存在语义启动效应, 字频与语义启动间不存在交互作用; 综合两个实验的ERP结果, 模糊度、字频和语义启动三者间存在交互作用, 且高频而非低频条件下模糊度与语义间也有交互作用, 无启动条件下字频和模糊度间也存在交互作用。本研究因此支持N400的IA模型(交互激活模型), 不支持核证模型和词汇后加工理论。     

听觉呈现条件下汉语双字词语义和语音启动的ERP研究

在词汇决定实验中研究语义启动和语音启动,材料为通过听觉呈现的汉语双字词组成的词对(间隔600ms),记录行为数据和ERP数据,结果发现：(1)启动词与目标词之间的语义联系可显著改善对目标词的加工,表现为错误率降低、反应时缩短,以及N400波幅降低;(2)启动词与目标词之间的语音一致对目标词的加工既有干扰作用,又有促进作用。表现为错误率提高,但反应时趋向缩短,N400波幅亦呈下降趋势;(3)启动词与目标词首音相同比尾音相同有更大的干扰作用。     

汉字刺激质量和频率在N400上的交互

采用事件相关电位,运用无启动的同一字判断（靶字延迟反应）范式,以大学生为被试探讨汉字刺激质量和频率是否具有交互作用。行为结果显示,刺激质量和频率在反应时上存在交互作用。脑电结果显示,重度模糊诱发了更大的N250和N400,且刺激质量和频率在N400上存在交互作用。结论是,汉字刺激质量和频率在反应时和N400上存在交互作用,表明在汉字识别中存在串级加工,支持IA模型。