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B MacWhinney

Publications and source records attributed to B MacWhinney.

12 recordsLinked to original sources
PubMed1992

The wheat and the chaff: or four confusions regarding CHILDES.

Edwards (1992) presents a set of examples from the Child Language Data Exchange System (CHILDES) as prototypes of bad transcription practice. Her discussion is based upon four basic confusions. First, Edwards confuses old and discarded versions of CHAT with current CHAT. Second, she confuses the relation between CHAT standards with the implementation of these standards during the process of reformatting older corpora. Third, she confuses transcription for automatic analysis with transcription for documentation. Fourth, she confuses the CHAT guidelines with the larger CHILDES system. We argue that these confusions have misled Edwards into developing an overly rigid set of principles for data analysis which, if followed literally, could choke off progress in the analysis of spontaneous language samples.

Archives↗
PubMed1991

Implementations are not conceptualizations: revising the verb learning model.

In a recent issue of this journal, Pinker and Prince (1988) and Lachter and Bever (1988) presented detailed critiques of Rumelhart and McClelland's (1986) connectionist model of the child's learning of the phonological form of the English past tense. In order to address these criticisms, a new connectionist model was constructed using the back-propagation algorithm, a larger input corpus, a fuller paradigm, and a new phonological representation. This new implementation successfully addressed the criticisms of the phonological representation used by Rumelhart and McClelland. It did a much better job of learning the past tense using a fuller input set with realistic frequencies of occurrence. Ancillary simulations using the same network were able to deal with the homonymy problem and the generation of forms like "ated" from "ate". The one feature not provided by the new model was a way of modeling early correct production of irregular forms. The success of the new model can be used to help clarify the extent to which the published critiques apply to a particular connectionist implementation as opposed to fundamental principles underlying the broader connectionist conceptualization.

Concept Formation↗
PubMed1991

A maximum likelihood procedure for the analysis of group and individual data in aphasia research.

The limitations inherent in group versus case studies appear to lie in a complementary distribution, underscoring the importance of combining both strategies within a single research program. However, this compromise approach requires analytic tools that permit us to combine and evaluate individual and group data in a common format. Maximum likelihood estimation (MLE) belongs to a family of procedures for determining goodness of fit. MLE can be used in conjunction with a linear or nonlinear model of the way that sources of information combine to determine a given behavioral outcome; such models can be used to estimate the distance between two groups, the degree to which an individual case deviates from a given empirically or theoretically defined group profile, and the degree to which one individual case resembles another. We offer a demonstration of how MLE can be used to evaluate group and individual profiles, in a cross-linguistic study of sentence comprehension in nonfluent aphasic speakers of English, Italian, and German. This includes a demonstration in which the MLE models for each language are "lesioned" to simulate several competing accounts of receptive agrammatism.

Aphasia↗
PubMed1991

Inflectional marking in Hungarian aphasics.

How do aphasics deal with the rich inflectional marking available in agglutinative languages like Hungarian? For the Hungarian noun alone, aphasics have to deal with over 15 basic case markings and dozens of possible combinations of these basic markings. Using the picture description task of MacWhinney and Bates (1978), this study examined the use of inflectional markings in nine Broca's and five Wernicke's aphasic speakers of Hungarian. The analysis focused on subject, direct object, indirect object, and locative nominal arguments. Compared to normals, both groups had a much higher rate of omission of all argument types. Subject ellipsis was particularly strong, as it is in normal Hungarian. There was a tendency for Broca's to omit the indirect object and for Wernicke's to omit the direct object. Across argument types, Wernicke's had a much higher level of pronoun usage than did Broca's. Broca's also showed a very high level of article omission. Compared to similar data reported by Slobin (this issue) for Turkish, the Hungarian aphasics showed an elevated level of omission of case markings. Addition errors were quite rare, but there were 14 substitutions of one case marking for another. These errors all involved the substitution of some close semantic competitor. There were no errors in the basic rules for vowel harmony or morpheme order. Overall the results paint a picture of a group of individuals whose grammatical abilities are damaged and noisy, but still largely functional. Neither the view of Broca's as agrammatic nor the view of Wernicke's as paragrammatic was strongly supported.

Adult↗
PubMed1991

Sentence comprehension in aphasia in two clear case-marking languages.

Studies of aphasia in Indo-European languages point to a selective vulnerability of morphological case marking in sentence comprehension. However, in case-marking languages such as German and Serbo-Croatian, the use of case marking to express formal grammatical gender diminishes the clarity of grammatical role marking. In Hungarian and Turkish, there are simple and reliable markings for the direct object. These markings are not linked to grammatical gender. Compared to Hungarian, the Turkish accusative marking is somewhat lower in availability, but somewhat higher in detectability. The processing of these cues by aphasics was tested using the design of MacWhinney, Pléh, and Bates (1985. Cognitive Psychology, 17, 178-209). Simple sentences with two nouns and one transitive verb were read to Broca's and Wernicke's aphasics, anomics, and control subjects in both Turkey and Hungary. The main effect of case marking was extremely strong. However, this was not true for all groups. The aphasics used the case cue far less than the normals, with the Hungarian Wernicke's group showing the greatest loss. Word order variations were largely ignored in all groups whenever the case-marking cue was present. When case marking was absent, Turkish subjects had a clear SOV interpretation for NNV sentences and Hungarians had a clear SVO interpretation for NVN sentences, in accord with basic patterns in their languages. When there was a contrast between the animacy of the two nouns, subjects choose the animate nouns significantly more often. The effect of animacy was particularly strong in Turkish, in accord with basic facts of Turkish grammar. In Hungarian, VNN sentences without case marking were interpreted as VOS when the first noun was inanimate. In Turkish, VNN sentences without case marking were often interpreted as VSO. In general, the aphasic subjects showed a clear preservation of virtually all aspects of their native languages, albeit in a much noisier form. Despite the high reliability of the case-marking cue, it was damaged more than the word order cue in English subjects. The near-chance processing of the case cue by the Wernicke's aphasics in Hungarian can probably be attributed to the relatively greater difficulty involved in detecting the Hungarian accusative suffix.

Anomia↗
PubMed1990

The Child Language Data Exchange System: an update.

In a previous issue of this Journal, MacWhinney & Snow (1985) laid out the basic sketch for an international system for exchanging and analysing child language transcript data. This system--the Child Language Data Exchange System (CHILDES)--has developed three major tools for child language research: (1) the CHILDES database of transcripts, (2) the CHAT system for transcribing and coding data, and (3) the CLAN programs for analysing CHAT files. Here we sketch out the current shape of these three major tools and the organizational form of the CHILDES system. A forthcoming book (MacWhinney, in press) documents these tools in detail.

Child↗
PubMedDate not supplied

Pragmatics in aphasia: crosslinguistic evidence.

Previous research suggests that English Broca's and Wernicke's aphasics retain sensitivity to pragmatic factors governing forms of reference, in particular the ability to choose lexical expressions that convey givenness and newness of information. The present study investigates the generality of this phenomenon across patients and language types. Normal and aphasic speakers of English, German, and Italian described nine picture triplets in which one element varied while the others remained constant. Dependent variables included lexicalization versus ellipsis, pronominalization, and definite and indefinite article use. For a subset of German and Italian patients, data were compared to performance in a biographical interview. Results indicate that (a) the pragmatics of reference are preserved in both Broca's and Wernicke's aphasics, despite syndrome-specific problems in retrieving content words and/or closed-class grammatical elements, and (b) certain language-specific patterns of reference are also preserved, including crosslinguistic differences in subject omission. Differences between picture description and the biographical interview reinforce this conclusion. Evidence for the preservation of pragmatics in aphasis is not surprising in its own right, but evidence for the sparing of language-specific relations among pragmatic, lexical, and morphosyntactic patterns can be used to argue against any strong view of grammatical impairment as a disconnection syndrome and/or a loss of grammatical competence. Instead, these data support theories in which grammatical impairment is viewed as a performance deficit.

Adult↗