Substitution as an Element of Coherence in the Discourse of Patients with Mixed Aphasia

Abstract

Substitution, understood as the replacement of a target lexical element with another, is a linguistic phenomenon that occurs both in the disturbed discourse and in the speech of healthy people. Any substitution of words in utterances undoubtedly affects the consistence of messages, and thus their interpretation by the interlocutor. This article examines what substitutions appear in the speech of healthy people and in people with mixed aphasia with a sensory and motor component. The article verifies the influence of lexical replacements on consistence at the microstructural level (cohesion) as well as how disruptions of microstructural consistency affect macrostructural consistency (coherence). The description of the research and analyses is preceded by reports from the literature, which demonstrate both an increased incidence of substitution and a reduced ability to maintain discourse cohesion and coherence in the speech of people with a diagnosis of mixed aphasia.