The effect of presentation rate on categorization

Homogeneous experimental (acoustically and semantically related) and control lists were presented to different groups of subjects at either 1 s or 6 s per word. The difference score between these two lists was used as a measure of categorization. Only words in the middle serial positions (representing retrieval from secondary memory) were scored. Clustering was also measured.

Slow presentation rate significantly increased categorization of the semantically similar words. This was not true of acoustically similar words. A possible explanation of this is that semantic categorization is time-consuming and acoustic categorization is not. Alternatively, the acoustic similarity effect may be a retrieval effect. The absence of acoustic clustering would seem to fit in with this latter interpretation.     

汉语听觉阈下启动效应：来自听觉掩蔽启动范式的证据

使用汉语双字词为实验材料,采用听觉掩蔽启动范式,通过3个实验考察汉语听觉阈下启动效应。结果发现,真词的听觉阈下重复启动效应显著,并且听觉阈下重复启动效应不受启动、目标发音者性别一致性的影响。但真词的阈下语音、语素和语义启动效应及假词的阈下重复和首字启动效应都不显著。这些结果说明,听觉通道阈下呈现的汉语双字词的词汇水平信息可以得到无意识加工。汉语双字词的听觉阈下启动效应可能是基于启动词整词表征的无意识激活。     

Interplay between acoustic/phonetic and semantic processes during spoken sentence comprehension: an ERP study

When listening to speech in everyday-life situations, our cognitive system must often cope with signal instabilities such as sudden breaks, mispronunciations, interfering noises or reverberations potentially causing disruptions at the acoustic/phonetic interface and preventing efficient lexical access and semantic integration. The physiological mechanisms allowing listeners to react instantaneously to such fast and unexpected perturbations in order to maintain intelligibility of the delivered message are still partly unknown. The present electroencephalography (EEG) study aimed at investigating the cortical responses to real-time detection of a sudden acoustic/phonetic change occurring in connected speech and how these mechanisms interfere with semantic integration. Participants listened to sentences in which final words could contain signal reversals along the temporal dimension (time-reversed speech) of varying durations and could have either a low- or high-cloze probability within sentence context. Results revealed that early detection of the acoustic/phonetic change elicited a fronto-central negativity shortly after the onset of the manipulation that matched the spatio-temporal features of the Mismatch Negativity (MMN) recorded in the same participants during an oddball paradigm. Time reversal also affected late event-related potentials (ERPs) reflecting semantic expectancies (N400) differently when words were predictable or not from the sentence context. These findings are discussed in the context of brain signatures to transient acoustic/phonetic variations in speech. They contribute to a better understanding of natural speech comprehension as they show that acoustic/phonetic information and semantic knowledge strongly interact under adverse conditions.     

Repetition priming of words and pseudowords in divided attention and in amnesia

Repetition priming of novel stimuli (pseudowords) and stimuli with preexisting representations (words) was compared in two experiments. In one, 19 normal male subjects performed a lexical decision task with either focused or divided attention. In another, lexical decision performance was compared between 8 male Korsakoff patients and 8 alcoholic control subjects. In control conditions, repetition speeded responses to both stimulus types. Experimental conditions that minimized the contribution of episodic memory to task performance eliminated reaction time priming for pseudowords but not for words. However, in these same conditions, repetition increased the likelihood that pseudowords would be incorrectly classified. These results indicate that preserved repetition priming effects in amnesia do not solely reflect activation of representations in semantic memory.     

The influence of acoustic and semantic similarity on long-term memory for word sequences

It has been shown that short-term memory (STM) for word sequences is grossly impaired when acoustically similar words are used, but is relatively unaffected by semantic similarity. This study tests the hypothesis that long-term memory (LTM) will be similarly affected. In Experiment I subjects attempted to learn one of four lists of 10 words. The lists comprised either acoustically or semantically similar words (A and C) or control words of equal frequency (B and D). Lists were learned for four trials, after which subjects spent 20 min. on a task involving immediate memory for digits. They were then asked to recall the word list. The acoustically similar list was learned relatively slowly, but unlike the other three lists showed no forgetting. Experiment II showed that this latter paradox can be explained by assuming the learning score to depend on both LTM and STM, whereas the subsequent retest depends only on LTM. Experiment III repeats Experiment I but attempts to minimize the effects of STM during learning by interposing a task to prevent rehearsal between the presentation and testing of the word sequences. Unlike STM, LTM proved to be impaired by semantic similarity but not by acoustic similarity. It is concluded that STM and LTM employ different coding systems.     

The effect of presemantic acoustic adaptation on semantic “satiation”

A decrement in the strength of the meaning of a word after rapid repetition of that word has been called “semantic satiation.” This study asked whether this “satiation” might be produced by presemantic acoustic adaptation. Category words were utilized to prime the meaning of target words. The adaptation or “satiation” procedure, 30 rapid repetitions of the primes, was compared with a control condition of 3 repetitions. Participants listened to a series of prime words, each repeated by either the same speaker or many speakers, and then made semantic decisions on target words. When all the repetitions of a prime word are produced by the same speaker, presemantic and semantic repetitions are confounded. When the repetitions are produced by different speakers, presemantic acoustic repetition is abolished. A semantic decrement was detected with single-speaker, but not with multiple-speaker, repetitions of prime words. This study concluded that the semantic “satiation” observed here was a decrement in the activation level of semantic representations induced by presemantic acoustic adaptation.     

Acoustic,semantic and phonetic influences in spoken warning signal words

Three experiments are reported which explore the relationship between semantic, acoustic and phonetic variables in the judgement of eight warning signal words. Experiment 1 shows that listeners can distinguish very clearly between urgent and non‐urgent versions of the words when spoken by real speakers, and that some signal words such as ‘deadly’ and ‘danger’ score more highly than words such as ‘attention’ and ‘don't’. It also shows that the three dimensions of perceived urgency, appropriateness and believability of these words are highly correlated. Experiment 2 replicates Experiment 1 using synthesized voices where acoustic variables are controlled. The semantic effects are replicated, and to some extent appropriateness and believability are found to function differently from that of perceived urgency. Experiment 3 compares the same set of eight signal words with a set of phonetically similar neutral words, showing that warning signal words are rated significantly higher, and largely maintain their previous rank ordering. Copyright © 2003 John Wiley & Sons, Ltd.     

Time course of word identification and semantic integration in spoken language

The minimum duration signal necessary to identify a set of spoken words was established by the gating technique; most words could be identified before their acoustic offset. Gated words were used as congruous and incongruous sentence completions, and isolation points established in the gating experiment were compared with the time course of semantic integration evident in event-related brain potentials. Differential N400 responses to contextually appropriate and inappropriate words were observed about 200 ms before the isolation point. Semantic processing was evident before the acoustic signal was sufficient to identify the words uniquely. Results indicate that semantic integration can begin to operate with only partial, incomplete information about word identity. Influences of semantic constraint, word frequency, and rate of presentation are described.     

Mapping from Sound to Meaning: Reduced Lexical Activation in Broca''s Aphasics

Recent studies of lexical access in Broca's aphasics suggest that lexical activation levels are reduced in these patients. The present study compared the performance of Broca's aphasics with that of normal subjects in an auditory semantic priming paradigm. Lexical decision times were measured in response to word targets preceded by an intact semantically related prime word ("cat"-"dog"), by a related prime in which one segment was acoustically altered to produce a poorer phonetic exemplar ("c*at"-"dog"), and by a semantically unrelated prime ("ring"-"dog"). The effects of the locus of the acoustic distortion within the prime word (initial or final position) and the presence of potential lexical competitors ("cat" --> /gaet/versus "coat" --> "goat") were examined. In normal subjects, the acoustic manipulations produce a small, short-lived reduction in semantic facilitation irrespective of the position of the distortion in the prime word or the presence of a voiced lexical competitor. In contrast, Broca's aphasics showed a large and lasting reduction in priming in response to word-initial acoustic distortions, but only a weak effect of word-final distortions on priming. In both phonetic positions, the effect of distortion was greater for prime words with a lexical competitor. These findings are compatible with the claim that Broca's aphasics have reduced lexical activation levels, which may result in a disruption of the bottom-up access of words on the basis of acoustic input as well as increased vulnerability to competition between acoustically similar lexical items.     

Phonology: A Review and Proposals from a Connectionist Perspective

A parallel distributed processing (PDP) model of phonological processing is developed, including components to support repetition, auditory processing, comprehension, and language production. From the performance of the PDP reading model of Plaut, McClelland, Seidenberg, and Patterson (1996), it is inferred that the acoustic-articulatory motor pattern associator that supports repetition provides the basis for phonological sequence knowledge. From the observation that many patients make phonemic paraphasic errors in language production, as in repetition, it is argued that there must be a direct link between distributed concept representations (lexical semantic knowledge) and this network representation of sequence knowledge. In this way, both lexical semantic and phonotactic constraints are brought to bear on language production. The literature on phonological function in normal subjects (slip-of-the-tongue corpora) and in patients with aphasia is critically reviewed from this perspective. The relationship between acoustic and articulatory motor representations in the process of phonetic perception is considered. Repetition and reproduction conduction aphasia are reviewed in detail and extended consideration is given to the representation of auditory verbal short-term memory in the model. Finally, the PDP model is reconciled with information processing models of phonological processing, including that of Lichtheim, and with current knowledge of the anatomic localization of phonological processing. Although no simulations of the model were run, a number of simulation studies are proposed.     

Processing of formational, semantic, and iconic information in American sign language

Three experiments examined short-term encoding processes of deaf signers for different aspects of signs from American Sign Language. Experiment 1 compared short-term memory for lists of formationally similar signs with memory for matched lists of random signs. Just as acoustic similarity of words interferes with short-term memory or word sequences, formational similarity of signs had a marked debilitating effect on the ordered recall of sequences of signs. Experiment 2 evaluated the effects of the semantic similarity of the signs on short-term memory: Semantic similarity had no significant effect on short-term ordered recall of sequences of signs. Experiment 3 studied the role that the iconic (representational) value of signs played in short-term memory. Iconicity also had no reliable effect on short-term recall. These results provide support for the position that deaf signers code signs from American Sign Language at one level in terms of linguistically significant formational parameters. The semantic and iconic information of signs, however, seems to have little effect on short-term memory.     

The effects of acoustic and semantic similarity on concept identification

Since both acoustic and semantic similarity exert an influence on memory, the role of memory in concept identification (CI) was investigated by varying the acoustic and semantic similarity of the stimuli used in the CI task. Varying acoustic similarity had no effect on CI, but CI was significantly impaired when the dimensions of a CI task were semantically similar.     

Repetition priming mediated by task similarity in semantic classification

In the present study, the specificity of repetition priming between semantic classification tasks was examined using Osgood's (Osgood, Suci, & Tannenbaum, 1957) semantic space as a heuristic for determining the similarity between classifications. The classification tasks involved judging the meaning of words on semantic scales, such as pleasant/unpleasant. The amount of priming across classifications was hypothesized to decrease with increasing distance (decreasing similarity) between semantic scales in connotative semantic space. The results showed maximum repetition priming when the study and the test classifications were the same, intermediate degrees of priming when the study and the test classification scales shared loadings on semantic factors, and little priming when the study and the test classification scales loaded primarily on orthogonal semantic factors--that is, when the distance between scales was maximized. Consistent with the transfer-appropriate processing framework, repetition priming in semantic classifications was highly task specific, decreasing with increasing distance between classification scales.     

Comparing Short-term Memory and Memory for Rapidly Presented Visual Stimuli

What similarities and differences are there between memory for short lists shown at one item per second and memory for such lists after rapid serial visual presentation (RSVP) at much higher rates—eight items per second? This paper reports that, when pictures are shown at eight per second or one per second, phonological similarity of the picture names reduces recall at the one item per second rate, but not at the eight item per second rate. In contrast, when subjects are shown the written names of the pictures, phonological similarity reduces recall at both rates. It is concluded that phonological coding does not occur for picture lists shown at high rates. The mechanisms underlying memory for pictures and words shown at RSVP and short-term memory rates are considered.     

Deep dysphasia: analysis of a rare form of repetition disorder

"Deep dysphasia" is the parallel in repetition to the reading impairment deep dyslexia. Our patient, S.M., showed part of speech, word/nonword, and concreteness effects in repetition, and he made semantic errors, but his oral reading was relatively spared. Further testing indicated that S.M. did not have difficulty perceiving spoken stimuli or deciding their lexical status, but he was deficient at semantically processing spoken words. Moreover, his phonemic memory was severely impaired. We argue that the routes for repetition (lexical and nonlexical) that function without semantic mediation were defective and that deficits in phonemic memory further diminished their effectiveness, since initial phonological encoding of spoken words was not available to guide the output stages of phonological processing. In addition, the semantically mediated route for repetition was unreliable because semantic processing was faulty and S.M. could not accurately label concepts.     

创造性思维中语义搜索过程：基于答案累积时间函数和语义相似性的量化分析

通过描绘发散性思维测验(物品多用途, AUT)中答案生成在累积函数和语义相似性等一系列参数上的量化特征, 揭示创造性思维的语义搜索过程。结果发现：(1)新颖AUT条件中, 语义搜索呈现与自由联想类似的负加速特点, 但搜索速度较寻常AUT条件更慢。(2)新颖AUT条件中所生成的答案与题目(即物品)均具有较低的语义相似性, 且显著小于寻常AUT条件。(3)新颖AUT条件中生成的答案比寻常AUT条件表现出显著更低的聚类程度, 其中可聚类答案和未聚类答案与题目的语义相似度均较低, 且不存在显著差异, 二者在新颖性上也不存在显著差异。以上结果说明了创造性思维的语义信息搜索过程具有与自由联想类似的激活扩散特征, 但总体搜索速度较慢。新颖性要求使得个体在最初搜索时便开始摆脱题目的语义限制而进行远距离搜索(避免就近搜索), 并倾向于在每个语义场中只生成一个答案(避免局部搜索), 但也可能会在远离题目的语义场中生成多个同类别答案。     

韩-汉跨语言词义水平的重复知盲效应*

关于语义水平的重复知盲效应一直存在争论。本研究考察非平衡韩-汉双语者在语言内和语言间词义水平的RB效应。实验1采用韩语双字词为实验材料探究韩语语言内的RB效应,结果表明在韩语词汇水平存在RB效应。实验2采用两个关键词为韩语（R1）和汉语（R2）双字词,并通过韩-汉语间隔词W的语言类型变化探究韩、汉语言间的RB效应,结果表明：不同语言类型的间隔词的正确率有显著差异,语义重复词R2在重复条件的正确率显著高于非重复条件,出现语义重复启动效应。本研究结论是：（1）在韩语语言内词水平存在RB效应,具有语言类型普遍性;（2）韩、汉跨语言语义水平出现语义重复启动效应,而未发生RB效应,表明双语者在加工韩、汉两种语言时,采用分别形式表征和共享语义表征的方式。     

Remembered study mode: Support for the distinctiveness account of the production effect

The production effect is the finding that words spoken aloud at study are subsequently remembered better than are words read silently at study. According to the distinctiveness account, aloud words are remembered better because the act of speaking those words aloud is encoded and later recovery of this information can be used to infer that those words were studied. An alternative account (the strength-based account) is that memory strength is simply greater for words read aloud. To discriminate these two accounts, we investigated study mode judgements (i.e., “aloud”/”silent”/”new” ratings): The strength-based account predicts that “aloud” responses should positively correlate with memory strength, whereas the distinctiveness account predicts that accuracy of study mode judgements will be independent of memory strength. Across three experiments, where the strength of some silent words was increased by repetition, study mode was discriminable regardless of strength—even when the strength of aloud and repeated silent items was equivalent. Consistent with the distinctiveness account, we conclude that memory for “aloudness” is independent of memory strength and a likely candidate to explain the production effect.     

Can repetition avoidance in randomization be explained by randomness concepts?

Summary A randomness concept hypothesis of repetition avoidance in socalled randomization tasks was studied. The alternative hypothesis proposed is the control hypothesis, which claims that repetition avoidance is caused by the attempts of the subjects to avoid perseveration. Three sequential response production tasks (number randomization, tone randomization, and production of a pleasing tone sequence), one randomness-judgement task, and four perseveration measures were presented to the subjects. Repetition avoidance was found in all three production tasks, including the tone productions in the pleasing condition. Correlations of the randomness judgements with repetition avoidance were generally not found. There was only slight evidence of correlations between the perseveration measures and repetition avoidance. The results suggest that randomness concepts do not contribute to repetition avoidance to any great extent. The control hypothesis is proposed to explain the results.     

The effect of visual and acoustic similarity on short-term memory for chinese words

Four lists of Chinese words in a 2 × 2 factorial design of visual and acoustic similarity were used in a short-term memory experiment. In addition to a strong acoustic similarity effect, a highly significant visual similarity effect was also obtained. This was particularly pronounced in the absence of acoustic similarity in the words used. The results not only confirm acoustic encoding to be a basic process in short-term recall of verbal stimuli in a language other than English but also lend support to the growing evidence of visual encoding in short-term memory as the situation demands.