Linguistics of altered states of consciousness, forming an integral part of general linguistics, especially designed for study, prediction and verbal correction of relatively short-time non-pathological deviations in cognitive and/or communicative performance, conditioned primarily by action of psychoactive substances, stress or meditative practices, is introduced. Correlates of continual and discrete alterations of consciousness on various strata of the linguistic system, including the phonological, morphological, syntactic, and lexical levels, are tentatively outlined. 'Middle-range linguistic concepts', seeming especially constructive for their study, are determined, from prototype theory of T. Givn to the linguistic synergetics elaborated by R.G. Piotrowski.