Articulatory defects in aphasia

Broca's faculté du langage articulé: Language or Praxis?

De Oliveira-Souza, Moll, and Tovar-Moll (this issue) historically reevaluate that Paul Broca's aphemia should be considered as a kind of apraxia rather than aphasia. I argue that such a claim is unwarranted, given the interpretation of the faculty of speech Broca derived from his predecessors, Jean-Baptiste Bouillaud and Franz Joseph Gall, and also with a view on the then generally held opinion that the terms aphémie and aphasie were synonyms. I will discuss evidence that patients such as Leborgne, producing only very few words or syllables, suffer from a global aphasia, affecting all modalities, despite Broca's statement that Leborgne's comprehension was intact. I also point to Broca's claim that the faculty of speech, located in the left anterior hemisphere, is independent from hand preference because it is an intellectual and not a motor function, and to his statement that the cerebral convolutions are not motor organs. I finally contend that, in order to determine whether a given language problem should be labeled as aphasia or apraxia, it is crucial to first be clear on the components of old and new models of language production.

Cerebral localisation in articulatory dyspraxia

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Linguistic Universals: Implications of a Neurological Reappraisal of Jakobson's Phonological Hierarchy

An ongoing research project designed to test Jakobson's claim of a universal rank order among the elements of phonological systems is described and illustrated. The strategy is that of close analysis, on surface, feature and neuromuscular levels successively, of phonetically deviant L2 performance data. While the first two analytical stages tend to corroborate the existence of widely valid cross-language constraints, the third yields evidence for an explanatory hypothesis in terms of the properties of participant neuromuscular mechanisms. It is argued that this ‘physiological hypothesis’ is superior to rival ‘nativist’ postulates in placing Jakobson's hierarchy on a firm ontological footing.

Phonemic behavior of aphasic subjects without dysarthria or apraxia of speech

Thirty adult aphasic subjects without apraxia of speech or dysarthria were tested for their ability to produce phonemes in single test words and in spontaneous contextual speech. Results indicated that 75% of the total phonemic errors were due to a whole-word phenomenon apparently associated with faulty processing of the word rather than faulty production of the phoneme. True phonemic errors comprised 25% of the total errors or about 2% of all responses. Phoneme substitutions were by far the most frequent error (61%). Of the 30 subjects, 28 made no phonemic errors in spontaneous contextual speech. Aphasic behavior is not characterized by significant breakdown of articulatory performance. Observed patterns of error do not clearly support a phonemic regression hypothesis.

CORTICAL DYSARTHRIA AND DYSPROSODY OF SPEECH

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