Some aspects of language comprehension in anterior aphasia

The competency of language comprehension was evaluated in three groups: anterior aphasics, posterior aphasics, and normal control subjects. Test material was divided into two sentence groups (Fill in the Blank and True/False) emphasizing either (1) semantic, “real world,” identity words or (2) syntactic, relational words, and one paragraph interpretation task. Matching auditory and visual (written) presentations were given. The control subjects performed almost flawlessly but many errors were made by each aphasia group. Qualitative study revealed a marked difference in the comprehension problem of the two groups. The anterior aphasic group performed well on semantically weighted sentences but made errors on syntactically weighted material, regardless of mode of presentation. In contrast, the posterior aphasics made almost the same number of errors on both types of material, regardless of mode of presentation. These findings support the concept of defective language comprehension in anterior aphasia and further suggest that the defect centers on the syntactical structures which are also poorly handled in expressive output.     

Time for auditory processing of object names by aphasics

Ten Wernicke's and ten Broca's aphasics were compared with normal controls and brain-damaged nonaphasics with respect to the time required for the auditory decoding of object names. This value was obtained by using a subtraction method with two reaction time determinations, one of which included an auditory processing phase while the other did not. The overall mean of approximately 200 msec for Broca's aphasics did not differ significantly from the normal, while the mean of 650 msec for the Wernicke aphasics was much slower. All groups responded more quickly to high-frequency than low-frequency words and all but the Wernicke aphasics improved in the second trial block over their performance in the first trial block.     

Organization of and access to semantic memory in aphasia

Previous experiments with picture sorting and matching tasks have shown aphasics to give more deviant responses than controls when decisions require the identification of single features of concepts, whereas their responses are close to normal whenever decisions have to be based on the relative overlap of broad associative fields. The present experiment was designed to compare picture matching based on single features (property verification) with picture matching based on category membership (category verification). Fifty-five aphasics (14 amnesics, 18 Brocas, 13 Wernickes, 10 global aphasics) and 29 right-brain-damaged control patients served as subjects. Aphasics were poorer than right hemisphere controls on property as well as on category sortings, especially when the sorting criterion was not a dominant property of the object or when the object in question was not a typical member of the criterion category. Contrary to other studies, the "semantic distance" variable did not differentially affect Brocas as compared to Wernickes aphasics. Verbal labels denoting the sorting criterion and added to the picture presentation did not affect the performance of the right hemisphere controls but significantly improved that of the aphasics.     

Lexical knowledge in anterior and posterior aphasics

A semantic categorization task was used to assess the structure of lexical knowledge in anterior and posterior aphasics. In general responses were faster for typical category members than for atypical ones and slower for semantically related nonmembers than for unrelated ones. Both groups performed at a high level of accuracy when classifying typical category members and semantically unrelated nonmembers. Their performance diverged at the category boundary. Anterior aphasics maintained relatively high levels of accuracy when classifying atypical category members and semantically related nonmembers while posterior aphasics did not. These results point to differences in the status of lexical knowledge for anterior and posterior aphasics.     

The game of the name: An examination of linguistic reference after brain damage

Two aspects of naming have generally been examined in aphasics: the appreciation of a single property of a concept and the ability to use the names of fully elaborated concepts. In applying to aphasics a recently proposed model of semantic organization—one which allows the simultaneous examination of these two aspects—two studies were conducted: Anterior and posterior aphasics were asked (1) to name members of superordinate categories, their responses being converted into prototypicality scores (the degree to which a member of a category resembles an ideal member of that category) and (2) to differentiate between more or less prototypical members of a category and their superordinates. The results revealed that, while anterior and posterior aphasics differ in their use of the names representing fully elaborated concepts, these groups show no differences in terms of the appreciation of a single property of a concept. The implications of these findings for reference were discussed.     

A study of spelling in aphasia

To secure systematic information on spelling abilities following damage to the dominant hemisphere, a test probing performance in three modalities of response was administered to a group of aphasic patients. Except for a predictable deficit among anterior aphasics in oral spelling, anterior and posterior aphasics exhibited comparable performances on the measures of spelling. However, anterior and posterior aphasics differed from one another on the kinds of words they most accurately spelled, the errors they were prone to make, and certain strategies which they characteristically adopted. These results suggest two alternative approaches to spelling: one approach, common in posterior aphasics, entails choosing letter combinations on the basis of their customary sounds; a second approach, common among anterior aphasics, appears to rely on a partially preserved image of the word's appearance.     

Recall failure following successful generation and recognition of responses by alcoholic Korsakoff patients

Amnesic Korsakoff patients and controls were presented with twelve words, each shown individually in the presence of a weak associate. They were then asked to freely associate to 12 other words that were strong associates of the to-be-remembered (TBR) words. The Korsakoff patients generated, and were able to recognize, as many of the TBR words as the controls. Yet, in spite of this recognition ability, these same patients were subsequently unable to recall the critical TBR words when the weak cues were again presented. A follow-up study found that the same recognition results could be obtained with Korsakoffs months after initial presentation suggesting that the patients might initially have “recognized” the most highly associated words simply because they represented the most probable choices. Intermediate association prompts failed to generate correct responses. It was hypothesized that the Korsakoff patients cannot restructure their semantic associative hierarchy during input in such a way as to become sensitized to other than the strongest associates as prompts during recall.     

Increased susceptibility of aphasics to a distractor task in the recall of verbal commands

The ability of 15 control, 15 nonaphasic brain-damaged, and 15 aphasic patients to carry out three-word commands on the Token Test was studied under three conditions: no delay, 20-sec unfilled delay, and 20-sec delay filled with a counting task. Only aphasics with mild to moderate comprehension deficit participated in the experiment and their scores in the no-delay condition were not inferior to those of the other two groups. The 20-sec unfilled delay did not bring about a decrement of the performance in any group, while all of them were impaired with 20-sec filled delay. The rate of forgetting was, however, significantly greater in aphasics than in patients without language disorders, even when the scores of the no-delay condition were introduced as covariates in the analysis of the filled-delay condition. The same result was obtained when, in a second experiment, 4 sec elapsed between the end of the command and the beginning of the counting activity. The increased susceptibility of aphasics to the disruptive effect of the distractor task is viewed as following a failure in organizing verbal information, a deficit that may contribute to lowering their comprehension level.     

Reconstructive retrieval deficits in Broca's aphasia

Anterior aphasic patients' ability to utilize the phonemic and/or semantic features of verbal material for retention purposes was investigated. In the first experiment, patients were asked to either detect word repetitions, phoneme repetitions, or rhymes in a list of items. The aphasics performed well on word and phoneme repetition detection but below both normals and amnesic Korsakoffs on rhyme detection. In the second experiment the patients were instructed to analyze either the physical, phonemic, or semantic features of words they were later asked to recognize. Aphasics were differentially affected (as were normals) by these instructions: semantic feature analysis resulted in the best performance, followed by phonemic feature analysis. It was concluded that anterior aphasics can analyze, recirculate, and even store the phonemic features of words, but find difficulty in reconstructing the originally presented item from these features.     

Speech production mechanisms in aphasia: A delayed auditory feedback study

Data collected from a delayed auditory feedback (DAF) study conducted by F. Boller, P. B. Vrtunski, Y. Kim, and J. L. Mack (1978, Cortex, 14, 212–226) were reanalyzed to determine if speech quality measures which were significantly affected during DAF could be operationalized and to ascertain which type of errors are responsible for the judgement. A second goal of this study was to determine if Conduction aphasics were relatively spared under conditions of DAF, as has been shown in previous studies. Twenty aphasic patients and ten controls were presented with several speech production tasks under two delay conditions and two simultaneous feedback conditions. Results indicated that only the category of vowel length produced a significant number of errors, suggesting that DAF affects articulatory implementation. Conduction aphasics showed the least effect of all the groups. These results support Wernicke's and Geschwind's model, in which Conduction aphasics have a disconnection between the sensory and motor images of words. In contrast, Broca's aphasics were the most affected group under DAF, suggesting that a major component of their disorder is phonetic in nature.     

Semantic classification in aphasia: A study of basic, superordinate, and function relations

Nonfluent and fluent aphasics were given classification tasks that required the aphasics to identify three kinds of relations: same basic level category, same superordinate level category, and same function. The subjects received the items in word and picture form. In addition the aphasics were required to name the items they were asked to classify. The results showed that the ability to classify is more disrupted in fluent aphasia than in nonfluent aphasia. Within fluent aphasia, the degree to which classification is disrupted is dependent upon the type of relation being tested. While the overall performance of the fluent aphasics was depressed in comparison to nonfluent aphasics, it was significantly more depressed on function relations. The ability to name an item had a significant effect on the ability to classify only for basic level items.     

The relation between gesture and language in aphasic communication

Effective communication in aphasia depends not only on use of preserved linguistic capacities but also (and perhaps primarily) on the capacity to exploit alternative modalities of communication, such as gesture. To ascertain the capacity of aphasic patients to use gesture in their spontaneous communication, informally structured interviews were conducted with two Wernicke's aphasics and two Broca's aphasics, as well as with four normal controls. The performances of the patient groups were compared on the physical parameters of gesture, the points in the communication where gestures occurred, and several facets of the semantics and pragmatics of gesture. Generally speaking, the gestures of the aphasics closely paralleled their speech output: on most indices, the performance of the Wernicke's aphasics more closely resembled that of the normal controls. Wernicke's aphasics differed from normals in the clarity of their language and gestures: While individual linguistic units were often clear, the relation among units was not. In contrast, the Broca's aphasics equaled or surpassed the normal controls in the clarity of their communications. The results offer little support for the view that aphasic patients spontaneously enhance their communicative efficacy through the use of gesture; these findings can, however, be interpreted as evidence in favor of a “central organizer” which controls critical features of communication, irrespective of the modality of expression.     

105例额叶、非额叶肿瘤患者词语流畅性作业的比较研究

让４８例额叶肿瘤患者,２６例颞叶肿瘤患者,２６例顶枕叶肿瘤患者,５例额颞肿瘤或颞顶肿瘤患者（全部病人分为左脑肿瘤５６例,右脑肿瘤４９例）说同类词,说非其类词及Ｓｔｒｏｏｐ测验。结果表明：１．额叶组说同类词总和明显低于颞叶组。２．额叶组读色字及读字色两项任务所用时间明显长于颞叶组及顶枕叶组。３．额叶组读色字及字色出现的错误频率明显高于正常人组及顶枕叶组。４．左脑肿瘤组说同类词及读黑色、色字及颜色命名的成绩明显低于右脑肿瘤组。资料提示：额叶肿瘤比颞叶与顶枕叶肿瘤、左脑肿瘤比右脑肿瘤更容易影响被试的词语记忆能力、选择性注意能力及分类归属能力。     

The effect of associations and expectations on lexical decision making in normals, alcoholics, and alcoholic Korsakoff patients

This study examined whether patients with Korsakoff's disease suffer from increased PI during encoding. The ability of the name of one category, e.g., BIRD, to prime the processing of members of another category, e.g., BODY PARTS, in a lexical decision task was used to assess the amount of PI during encoding. This task required a subject to inhibit the normal associations to BIRD. Young normals (25 years), older normals (48 years), alcoholics (45 years), and alcoholic Korsakoff patients (59 years) performed two lexical decision tasks. In the first experiment, the appearance of the neutral prime XXX 750 msec before the probe signaled that if the probe was a word, there was a 75% chance that it was from a particular category (e.g., BODY PARTS). The prime facilitated reaction time for words from the expected category for all four groups. The prime slowed reaction time for words that were not from the expected category for the young normals but did not influence reaction time for unexpected words for the three older groups. The second experiment was identical to the first except that a category word was used as the prime. The category word used as the prime was unrelated to the category of the words that were likely to follow it. For example, BIRD might be used to signal the likelihood that the word would be from the category, BODY PARTS. Again, young normals were slower to respond to unexpected probe words, but the three older groups were not. Again, the prime facilitated reaction time for expected words for the young normals, older normals, and alcoholics. However, the word prime did not facilitate reaction time for expected words for the alcoholic Korsakoff patients. That the word prime did not facilitate reaction time for the Korsakoff patients was viewed as evidence that they were unable to inhibit its normal associations and were more sensitive to PI from these associations than the other subjects.     

The spacing effect in the learning of word pairs

Following the presentation of a single list of word pairs consisting of a three-letter word on the left and a five-letter word on the right, groups of 64 Ss each were asked to recall the (a) three-letter words, (b) five-letter words, (c) intact pairs, or (d) five-letter words with the three-letter words provided. Two types of repeated pairs were presented, one in which the same three- and five-letter words were repeated together (same pairs) and one in which the same five-letter word was repeated with different three-letter words (different pairs). For half of the Ss in each recall group, the repetitions of a pair containing a given five-letter word were massed (MP); for the other half, the repetitions were distributed (DP). Recall of MP same pairs and the eomponents of these pairs was consistently poorer than that of DP same pairs. Recall of the repeated component of the different pairs was also poorer under MP than under DP. The results were interpreted as supportive of an attenuation-of-attention explanation of the spacing effect.     

The mapping from sound structure to the lexicon in aphasia: evidence from rhyme and repetition priming

Two studies were conducted to explore the hypothesis that Broca's and Wernicke's aphasics have deficits arising from the processes involved in activating the lexicon from phonological form. The first study explored whether phonologically similar lexical entries differing only in their initial consonants show "rhyme priming." Results revealed that Broca's aphasics failed to show facilitation when the target was identical to the prime (i.e. identity priming) and they showed significant inhibition when targets were preceded by rhyming words. Wernicke's aphasics showed a pattern of results similar to that of normal subjects, i.e., identity priming and rhyme priming as well as significantly slower reaction-times in the rhyming condition compared to the identity condition. The second study investigated form-based repetition priming in aphasic patients at a number of intervals including when no other stimuli intervened between repeated stimuli (0 lag) or when 4, 8, or 12 stimuli intervened. Results showed that, unlike old normal subjects who showed repetition priming for both words and nonwords, both Broca's and Wernicke's aphasics showed repetition priming for word targets only. Moreover, in contrast to old normal subjects who showed a greater magnitude of priming at 0 lag for word targets, neither Broca's aphasics or Wernicke's aphasics showed priming at 0 lag. Implications of these findings are considered with respect to the hypotheses that Broca's and Wernicke's aphasics have deficits in the nature of the activation patterns within the lexicon itself and in auditory (working) memory.     

汉语颠倒词加工中重复知盲发生的水平

以汉语中的颠倒词为材料, 探讨汉语重复知盲的发生水平。采用RSVP方式呈现包含颠倒词对(C1和C2)的句子列表或词语列表, 让被试对列表中的词进行全部报告或报告是否存在重复词, 记录报告C2的正确率。三个实验采用3 (词语的重复性: 颠倒重复、完全重复、不重复) × 2 (颠倒词对的意义相似性: 意义不同、意义相似)两因素被试内设计, 结果在全部报告和报告是否存在重复词的实验中都出现重复性和意义相似性的交互效应, 但不同实验任务, 数据模式不同。该结果表明, 在RSVP任务中, 汉语颠倒词加工存在RB效应, 该效应产生的水平受制于不同的实验任务, 在部分报告任务中, 颠倒词的RB效应发生在知觉水平, 在全部报告任务中, 颠倒词的RB效应发生在语义水平。     

Mechanisms underlying writing and speech in aphasia

As a parallel to the dual decoding concept for processing of written language we proposed that phonological encoding does not necessarily occur in writing and that the phonemic and graphemic subsystems can be independent on the one-word level. This hypothesis was tested by comparing oral and written performance in a picture-naming task in Broca's and Wernicke's aphasics. In addition, the residual tacit knowledge of the orthographic properties of the names of the pictures was examined with a multiple-choice recognition task. The principal finding is that Broca's aphasics who were better in written than in oral naming showed more graphemically and semantically motivated errors than aphasics who were better in oral than in written naming, the latter producing more phonemically motivated errors. This result supports the dual encoding concept for writing on the singleword level, implying a direct route from the mental lexicon to the graphemic system in parallel with a route mediated by the phonemic system. Multiple-choice recognition was found to be superior to both oral and written performance in both Broca's and Wernicke's aphasics.