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Eighteen patients (11 male, 7 female) with left thalamic haemorrhage confirmed by CT-scan of the brain were investigated for their language function. Aphasia Test for Turkish Citizens modified from Mayo Clinic Aphasia Test and Boston Diagnostic Aphasia Examination were given for evaluating the language modalities. Fluent aphasia was observed in 16 subjects (with paraphasia in 8 and hypophonia in 3). Dysarthric speech output was seen in 2 cases. Repetition and naming were well preserved while comprehension was moderately affected. This type of aphasia differs considerably from the classical aphasias and its rapid recovery is a very prominent feature.

A survey is given on the history of knowledge of aphasia and on the necessity and possibilities of classification of aphasic disability. Also the association of clinical syndromes of aphasia with particular damage to the brain is outlined. For Wernicke's aphasia (fluent aphasia with comprehension deficit) a superior posterior temporal lesion is obligatory. The persistent jargon aphasia is associated with a lesion of the supramarginal gyrus. Broca's aphasia is seen with posterior inferior frontal lesions, but additional central and subcortical components are involved in persisting deficit. The lesions producing transcortical motor aphasia involve the supplementary speech area of Penfield. Transcortical sensory aphasia is related to lesions that overlap the watershed area between the middle cerebral and the posterior cerebral arteries.

We argue that the lesion localizing value of disruptions to modular information processing systems emerges most clearly from on-line analyses of processing. In this respect we seek to show that left anterior (but not left posterior) damage causes slowed information access and we discuss the manner in which this slowing might yield some of the specific syntactic limitations charted in Broca's aphasia. The general possibility we raise is that the cortical area implicated in Broca's aphasia is not necessarily the locus of syntactic representations, but rather sustains particular time-based operating characteristics that in turn sustain normal real-time parsing.

Ten fluent and ten nonfluent aphasics participated in this study. Their ability to comprehend before and after clauses which mirrored the order of occurrence and those which did not mirror the order of events was investigated. Results indicate that type of aphasia was not a significant variable related to comprehension but that sentence type was a significant variable. Aphasics' comprehend before clauses better than after clauses. Nonfluent aphasics were able to comprehend those temporal clauses that mirror the order of occurrence better than those that do not. Order of mention was not a significant factor related to comprehension in the fluent group.

Thirty-seven aphasic patients whose native language is Spanish were divided into four groups: (1) Broca's, (2) Wernicke's, (3) Conduction, and (4) Anomia. Phonological errors produced on repetition and object-naming tasks were analyzed in terms of type of transformation and degree of similarity between target and errors in terms of shared distinctive features. Segmental transformations were of the following types: (1) pure substitution, (2) pure addition, (3) deletion, (4) reduplicative addition (doublet creation)--anticipatory (right to left) or preservative (left to right), (5) reduplicative substitution (doublet creation)--anticipatory or perseverative, and (6) mutual exchanges. Pure substitutions were the most prevalent, exchanges, the least. Some error types were found to differentiate significantly between aphasic populations. We suggest that different mechanisms may underlie the same error type for different aphasic populations.

A cluster analysis, based upon the naming errors of 61 non-selected aphasiacs, was performed. Three clusters emerged; the first was marked by phonemic errors, the second by semantic ones and the third by the use of escape mechanisms. Subjects in the second cluster were less impaired; this could be a consequence of the disturbance type involved. Though many patients of first and third groups displayed a Wernicke aphasia, whereas Broca aphasia predominated in the second one, a concordance of clusters with aphasiologic diagnoses was far from excellent.