Bilingual retrieval from semantic memory

Bilinguals produced English and French words from two taxonomic categories. Analyses of outputs indicated they retrieved words by semantic category, but in clusters from the same language, half the subjects immediately translating the words retrieved. Translations aside, more shifts were across languages than across categories. Protocols also showed the same degree of semantic clustering and number of concepts retrieved as those of other bilinguals responding unilingually. The findings are consistent with separate lexicons for each language, tapping a common system of concepts. An alternative account is possible in terms of a single lexicon, organized along semantic lines, but with stronger links between words from the same language. This work was supported by a grant from the National Sciences and Engineering Research Council of Canada.     

嗓音源判断过程中的范畴效应和通道效应

该项研究通过设计4种实验条件,旨在探讨不同嗓音词的再认和嗓音判断过程各自的特点及其相互联系。4种实验条件是由2种诵读方式和2种测试方式组合而成,2种诵读方式为同范畴同嗓音和同范畴异嗓音,2种测试方式为视觉呈现和听觉呈现。52名大学生被试随机分成4个独立的组,分别接受一种实验处理。实验结果显示：(1)同范畴同嗓音条件与同范畴异嗓音条件相比,前者项目词的嗓音源判断效果好。提示增加相同记忆源项目间语义联系将有利于记忆源的检测判断。(2)项目再认与项目嗓音判断结果不完全一致,只有在诵读方式为同范畴同嗓音测试方式为听觉呈现情境下,两者有较高的正相关。(3)在同范畴同嗓音诵读条件下,再认反映出学习和测试通道源一致性优势效应,嗓音判断没有反映出通道源一致性优势效应。     

The role of category information in word identification: A parallel decision model

Four experiments consider the role of semantic category information in word identification using a serial classification reaction time paradigm. Experimental variables were manipulated by varying the semantic properties of blocks of trials and the target search instructions. Experiments 1, 2, and 3 investigated the facilitation on target word recognition of manipulating the categorical homogeneity of the nontarget words. An homogeneous nontarget set facilitated the classification of unrelated target words. This category contrast effect was obtained in all conditions, although its magnitude depended upon target search instructions. Experiment 3 also investigated whether word identification was inhibited if subjects were prevented from utilizing the category information to distinguish target from nontarget words. Target and nontarget word identification was slower under such conditions. Experiment 4 demonstratd that both the category contrast and category interference effects were dependent upon the use of short response-stimulus intervals to define a functional semantic background. This suggests the category effects are perceptual in nature. Current models of word recognition cannot easily explain the findings. A committee decision model is outlined to accommodate the data; the model proposes that visual analysis, identification, and categorization proceed in parallel.     

Semantic additivity and semantic inhibition: dissociable processes in the cerebral hemispheres?

We report the results of two visual half-field semantic priming experiments using a high proportion of related trials to examine hemisphere asymmetries for semantic processes beyond those attributable to automatic meaning activation. Contrary to previous investigations, we obtained inhibition for unrelated trials in both visual fields. However, priming was additive (being greater for words related via category membership and association than for either single dimension) only when words were presented to the RVF/left hemisphere. A third experiment, using centrally presented stimuli, implied that semantic additivity should be attributed to post-access meaning comparisons and inhibition to the generation of semantic expectancies. These results suggest (1) that inhibition and additivity are potentially dissociable "controlled" semantic processes and (2) that the left hemisphere predominates for meaning integration across successively presented words. The availability of finely tuned meaning integration processes in the left hemisphere may contribute to its superiority in language processing, despite right hemisphere competence for some semantic operations.     

Similarity Judgment Within and Across Categories: A Comprehensive Model Comparison

Similarity is one of the most important relations humans perceive, arguably subserving category learning and categorization, generalization and discrimination, judgment and decision making, and other cognitive functions. Researchers have proposed a wide range of representations and metrics that could be at play in similarity judgment, yet have not comprehensively compared the power of these representations and metrics for predicting similarity within and across different semantic categories. We performed such a comparison by pairing nine prominent vector semantic representations with seven established similarity metrics that could operate on these representations, as well as supervised methods for dimensional weighting in the similarity function. This approach yields a factorial model structure with 126 distinct representation-metric pairs, which we tested on a novel dataset of similarity judgments between pairs of cohyponymic words in eight categories. We found that cosine similarity and Pearson correlation were the overall best performing unweighted similarity functions, and that word vectors derived from free association norms often outperformed word vectors derived from text (including those specialized for similarity). Importantly, models that used human similarity judgments to learn category-specific weights on dimensions yielded substantially better predictions than all unweighted approaches across all types of similarity functions and representations, although dimension weights did not generalize well across semantic categories, suggesting strong category context effects in similarity judgment. We discuss implications of these results for cognitive modeling and natural language processing, as well as for theories of the representations and metrics involved in similarity.     

Evaluating the random representation assumption of lexical semantics in cognitive models

A common assumption implicit in cognitive models is that lexical semantics can be approximated by using randomly generated representations to stand in for word meaning. However, the use of random representations contains the hidden assumption that semantic similarity is symmetrically distributed across randomly selected words or between instances within a semantic category. We evaluated this assumption by computing similarity distributions for randomly selected words from a number of well-known semantic measures and comparing them with the distributions from random representations commonly used in cognitive models. The similarity distributions from all semantic measures were positively skewed compared with the symmetric normal distributions assumed by random representations. We discuss potential consequences that this false assumption may have for conclusions drawn from process models that use random representations.     

Effects of bilingualism, aging, and semantic relatedness on memory under divided attention.

We examined how encoding and retrieval processes were affected by manipulations of attention, and whether the degree of semantic relatedness between words in the memory and distracting task modulated these effects. We also considered age and bilingual status as mediating factors. Monolingual and bilingual younger and older adults studied a list of words from a single semantic category presented auditorily, and later free recalled them aloud. During either study or retrieval, participants concurrently performed a distracting task requiring size decisions to words from either the same or a different semantic category as the words in the memory task. The greatest disruptions of memory from divided attention (DA) were for encoding rather than retrieval. The effect of semantic relatedness was significant only for DA at encoding. Older age and bilingualism were associated with lower recall scores in all conditions, but these factors did not influence the magnitude of memory interference. The results suggest that encoding is more sensitive to semantic similarity in a distracting task than is retrieval. The role of attention at encoding and retrieval is discussed.     

Release from PI: An analysis and a model

Recall decreases across a series of subspan immediate-recall trials but rebounds if the semantic category of the words is changed, an example of release from proactive interference (RPI). The size of the rebound depends on the semantic categories used and ranges from 0% to 95%. We used a corpus of novels to create vectors representing the meaning of about 40,000 words using the BEAGLE algorithm. The distance between categories and spread within categories jointly predicted the size of the RPI. We used a holographic model for recall equipped with a lexicon of BEAGLE vectors representing the meaning of words. The model captured RPI using a hologram as an interface to bridge information from episodic and semantic memory; it is the first account of RPI to capture release at the level of individual words in categorized lists.     

Strength-based criterion shifts in recognition memory

In manipulations of stimulus strength between lists, a more lenient signal detection criterion is more frequently applied to a weak than to a strong stimulus class. However, with randomly intermixed weak and strong test probes, such acriterion shift often does not result. A procedure that has yieldeddelay-based within-list criterion shifts was applied to strength manipulations in recognition memory for categorized word lists. When participants made semantic ratings about each stimulus word, strength-based criterion shifts emerged regardless of whether words from pairs of categories were studied in separate blocks (Experiment 1) or in intermixed blocks (Experiment 2). In Experiment 3, the criterion shift persisted under the semantic-rating study task, but not under rote memorization. These findings suggest that continually adjusting the recognition decision criterion is cognitively feasible. They provide a technique for manipulating the criterion shift, and they identify competing theoretical accounts of these effects.     

The Micro-Category account of analogy

Here, we investigate how activation of mental representations of categories during analogical reasoning influences subsequent cognitive processing. Specifically, we present and test the central predictions of the "Micro-Category" account of analogy. This account emphasizes the role of categories in aligning terms for analogical mapping. In a semantic priming paradigm, a four-word analogy task was compared to two other four-word tasks. Stimuli were identical in all tasks; only the instructions given to participants differed. Participants were instructed to identify analogy relations, category relations, or conventionalized semantic relations in the four-word sets. After each four-word set, a single target word appeared and participants named this word aloud. Target words that referred to category relations in the preceding four-word sets were primed as strongly when participants identified analogies as when participants identified categories, suggesting that activation of category concepts plays an important role in analogical thinking. In addition, priming of category-referent words in the analogy and category tasks was significantly greater than priming of these words when participants identified conventionalized semantic relations. Since identical stimuli were used in all conditions, this finding indicates that it is the activation of category relations, distinct from any effect of basic semantic association, that causes analogical reasoning to prime category-referent words. We delineate how the "Micro-Category" account of analogy predicts these phenomena and unifies findings from diverse areas of research concerning analogical reasoning.     

语义相似性与类别大小对图-词干扰范式下语义效应的影响

采用基本水平命名和类别水平命名任务, 通过2个实验, 考察了图-词之间的语义相似性与类别大小对图-词干扰范式下语义效应的影响。实验1发现, 图片命名时间在语义相似性高的干扰词条件下显著快于在语义相似性低的干扰词条件下, 但这种效应只出现在基本水平命名任务中, 未出现在类别水平命名任务中。图-词之间的语义相似性高低对低熟悉图片命名影响大, 对高熟悉图片命名影响小。实验2显示, 语义关联的干扰词对图片的基本水平命名产生了语义干扰效应, 对图片的类别水平命名产生了语义促进效应。类别大小强化了语义效应：类别大, 图片的基本水平命名的语义干扰效应更大, 图片的类别水平命名的语义促进效应更强。整个研究表明, 图-词之间的语义关联的强度影响语义效应的方向, 图-词之间的语义关联的广度影响语义效应的强弱。需要结合多种理论来解释图-词之间的语义相似性和类别大小对图-词干扰范式下语义效应的影响。     

Buildup and release from proactive interference in a rhesus monkey

The potential of the buildup and release from proactive interference (PI) technique in the study of animal categorization was demonstrated with a rhesus monkey. A serial probe recognition task was used with a list of 4 consecutive slide pictures (upper screen) followed by a single probe picture (lower screen). The monkey moved a lever to indicate whether or not the probe was contained in the list. PI built over 40 consecutive trials tested with either flowers or primate faces. PI was released on category change and then built during 40 trials with the second category. The first 2 serial positions showed somewhat greater PI buildup and release, supporting conclusions from human studies that the effects occur primarily in secondary memory. A second experiment provided 2 replications of the main effect and showed through color border changes and elimination of color differences that color was not a critical feature.     

序列语义的类别一致性关系能否进行无意识整合？

阈下语义之间能否进行整合,最近的研究给出了不同的结果。当多个阈下语义词语同时呈现时显示出无意识语义整合效应,但是当序列呈现时没有观察到无意识整合效应。本研究在保留同时呈现方法优点（不同空间呈现位置）的情况下研究了序列呈现的不同汉字词语之间能否产生无意识语义类别关系整合。在实验1中,两个相同或不同类别的词语作为阈下启动刺激先后在两侧呈现,且第一个词语消失后第二词语马上出现,结果显示出无意识语义类别整合效应。实验2延长了两个阈下启动词语之间的时间间隔,结果未发现无意识语义类别整合效应。另外,实验3进一步排除了实验1中第一个启动词语的视觉残留,结果也未观察到显著的无意识语义类别整合效应,说明实验1中观察到的无意识整合效应是视觉残留所致。综合三个实验结果表明,两个阈下词语之间的语义类别一致性关系只有在同时呈现这种特殊条件下才能进行无意识整合加工,说明了短时间维度对于无意识语义关系整合的重要性。     

Refractory semantics in global aphasia: On semantic organisation and the Access–Storage distinction in neuropsychology

Abstract

A single case study is reported of a global aphasic patient, JM, with impaired access to semantic information which was particularly severe for the class of proper names. JM's ability to perform matching tasks with printed words and pictures to auditory words deteriorated when items were repeated, especially when the response–stimulus interval was short. Performance was also inconsistent across items. The effect of repeated testing on items generalised to other, previously untested members of the same category. Despite this, JM was able to access general semantic information about stimuli from the affected categories (e.g. to categorise boys' and girls' names), and showed good ability to access an input lexicon concerning these stimuli. There was also a close relationship between the categories affected when he was tested with pictures and printed words. We propose that JM's deficit can be attributed to his semantic system entering an abnormal refractory state once semantic access for a particular item has been achieved, and with this stage being isolated from the procedures providing access to stored lexical knowledge. Furthermore, the representations affected seem common to pictures and printed words. We discuss the implications of the results for understanding the nature of semantic representations in general and for proper names in particular, and for the distinction between access and storage deficits in neuropsychology.     

序列语义的类别一致性关系能否进行无意识整合？

阈下语义之间能否进行整合,最近的研究给出了不同的结果。当多个阈下语义词语同时呈现时显示出无意识语义整合效应,但是当序列呈现时没有观察到无意识整合效应。本研究在保留同时呈现方法优点（不同空间呈现位置）的情况下研究了序列呈现的不同汉字词语之间能否产生无意识语义类别关系整合。在实验1中,两个相同或不同类别的词语作为阈下启动刺激先后在两侧呈现,且第一个词语消失后第二词语马上出现,结果显示出无意识语义类别整合效应。实验2延长了两个阈下启动词语之间的时间间隔,结果未发现无意识语义类别整合效应。另外,实验3进一步排除了实验1中第一个启动词语的视觉残留,结果也未观察到显著的无意识语义类别整合效应,说明实验1中观察到的无意识整合效应是视觉残留所致。综合三个实验结果表明,两个阈下词语之间的语义类别一致性关系只有在同时呈现这种特殊条件下才能进行无意识整合加工,说明了短时间维度对于无意识语义关系整合的重要性。     

Testing an associative account of semantic satiation

How is the meaning of a word retrieved without interference from recently viewed words? The ROUSE theory of priming assumes a discounting process to reduce source confusion between subsequently presented words. As applied to semantic satiation, this theory predicted a loss of association between the lexical item and meaning. Four experiments tested this explanation in a speeded category-matching task. All experiments used lists of 20 trials that presented a cue word for 1 s followed by a target word. Randomly mixed across the list, 10 trials used cues drawn from the same category whereas the other 10 trials used cues from 10 other categories. In Experiments 1a and 1b, the cues were repeated category labels (FRUIT–APPLE) and responses gradually slowed for the repeated category. In Experiment 2, the cues were nonrepeated exemplars (PEAR–APPLE) and responses remained faster for the repeated category. In Experiment 3, the cues were repeated exemplars in a word matching task (APPLE–APPLE) and responses again remained faster for the repeated category.     

Category-structure effects in picture comparisons

Subjects indicated for a series of trials whether or not two pictures of common objects were from the same category. Reaction time (RT) was recorded. The pool of stimuli used in the series of trials consisted of two pictures representing each of several categories. Half were S categories, members of which were similar; the other half were D categories, which had dissimilar members (this variable is termed category structure). In Experiments 1 and 3, the similarity manipulation defining category structure was based on the concept of basic level categories (Rosch, Mervis, Gray, Johnson, & Boyes-Braem, 1976). In Experiment 2, category labels were homonyms, and the two members of S or D categories represented one or two senses of the labels, respectively. The principal finding was an effect of category structure (faster RT on trials using stimuli from S categories rather than D categories). These results are interpreted in terms of a model that postulates the use of semantic codes in the task, even on trials where the two stimuli are physically identical.     

Re-examination of “release-from-PI” phenomena: recall accuracy does not recover after a semantic switch

Recall accuracy decreases over successive memory trials using similar memoranda. This effect reflects proactive interference (PI) – the tendency for previously studied information to reduce recall of new information. However, recall improves if memoranda for a subsequent trial are semantically dissimilar from the previous trials. This improvement is thought to reflect a release from PI. We tested whether PI is reduced or released from the semantic category for which it had been induced by employing paradigms which featured inducement, semantic switch, and then return-to-original category epochs. Two experiments confirmed that PI was not released after various semantic switch trials (effects from d?=??0.93 to ?1.6). Combined analyses from both studies demonstrated that the number of intervening new category trials did not reduce or release PI. In fact, in all conditions recall accuracy decreased, demonstrating that PI is maintained and can increase after the new category trials. The release-from-PI account cannot accommodate these broader dynamics of PI. This account is also incongruent with evidence and theory from cognitive psychology, linguistics, and neuroscience. We propose a reintroduction-of-PI account which explains these broader PI dynamics and is consistent with the wider psychological and neurosciences.     

Perceptual and semantic sources of category-specific effects: event-related potentials during picture and word categorization

In two experiments the effect of object category on event-related potentials (ERPs) was assessed while subjects performed superordinate categorizations with pictures and words referring to objects from natural (e.g., animal) and artifactual (e.g., tool) categories. First, a category probe was shown that was presented as name in Experiment 1 and as picture in Experiment 2. Thereafter, the target stimulus was displayed. In both experiments, analyses of the ERPs to the targets revealed effects of category at about 160 msec after target onset in the pictorial modality, which can be attributed to category-specific differences in perceptual processing. Later, between about 300-500 msec, natural and artifactual categories elicited similar ERP effects across target and category modalities. These findings suggest that perceptual as well as semantic sources contribute to category-specific effects. They support the view that semantic knowledge associated with different categories is represented in multiple subsystems that are similarly accessed by pictures and words.     

Blocked vs. interleaved presentation and proactive interference in episodic memory

Although a number of theoretical accounts of proactive interference (PI) in episodic memory have been proposed, existing empirical evidence does not support conclusively a single view yet. In two experiments we tested the predictions of the temporal discrimination theory of PI against alternative accounts by manipulating the presentation schedule of study materials (lists blocked by category vs. interleaved). In line with the temporal discrimination theory, we observed a clear buildup of (and release from) PI in the blocked condition, in which all the lists of the same category were presented sequentially. In the interleaved condition, with alternating lists of different categories, a more gradual and smoother buildup of PI was observed. When participants were left free to choose their presentation schedule, they spontaneously adopted an interleaved schedule, resulting again in more gradual PI. After longer delays, we observed recency effects at the list level in overall recall and, in the blocked condition, PI-related effects. The overall pattern of findings agrees with the predictions of the temporal discrimination theory of PI, complemented with categorical processing of list items, but not with alternative accounts, shedding light on the dynamics and underpinnings of PI under diverse presentation schedules and over different time scales.