Operational words in aphasiacs

Abstract The authors propose a classification of words according to psycho-linguistic criteria, into conceptual and operational words. The words used in the communication process are shown to have different semantical tasks. This task is more important in conceptual than in operational words; having a less important semantical task, the latter words establish particularly the relationships between the words in a sentence. Encoding is therefore a double process including word selection and word succession. Succession is effected by using also logico-grammatical laws both by the operational words and by deployment of the conceptual ones. On this basis a linguisto-statistical analysis of prepositions and conjunctions (operational words) in aphasic speech (spoken language) was carried out. Ten patients with aphasia due to cerebral vascular disease and 10 normal control subjects were studied. 2500 words were collected from each subject by means of a standard interview. In aphasiacs alterations were found both in the number and particularly in the frequency of use of prepositions and conjunctions; and yet, those most frequently employed in normal speech were preserved in direct proportion to the amount of the individual vocabulary which survived, but their frequency of use was greatly modified. The aphasiacs manifested individual preferences for some prepositions and conjunctions and neglected or completely lost others. In general, the disturbances were of greater importance with respect to conjunctions than to prepositions.