This article examines the problem of distinguishing between language and speech abilities in the context of the evolution of linguistic and psychophysiological theories. The aim of the study is to systematize classical approaches and compare them with modern neurobiological and cognitive data. The methodological framework consists of an interdisciplinary synthesis of structural-semiotic, generative, and clinical-neuropsychological approaches. The results show that language ability and speech ability are not identical: the former is an invariant system of rules and lexical representations, while the latter is a dynamic process of actualizing this system in real time, subject to psychophysiological constraints. Based on the material of motor and sensory aphasias, the possibility of dissociation of these phenomena under local brain lesions is substantiated. Practical recommendations for speech therapy, pedagogy, and evaluation of artificial intelligence systems are proposed
aphasia
aphasiology
artificial intelligence
bilingualism
cognitive linguistics
competence
language ability
neurolinguistics
performance
psycholinguistics
speech ability
speech production