Koartikulaatio

Koartikulaatio (Finnish for coarticulation) is a phenomenon in speech production where the articulation of a given sound is influenced by surrounding sounds, leading to overlap between articulatory gestures. In fluent speech, articulators such as the lips, tongue, and jaw begin preparing for the next segment while the current one is still being produced. This overlap is a normal, productive property of speech, contributing to natural variability but also to robust speech perception.

Coarticulation can be described as anticipatory or carryover. Anticipatory coarticulation occurs when the articulation of the upcoming sound affects the current sound, for example when lips begin to round in advance of a following labial consonant. Carryover coarticulation happens when the articulation of a preceding sound influences the current one, such as lingering tongue position after a velar consonant affecting the ensuing vowel. The extent of coarticulation varies across languages, speaking styles, and individual speakers, reflecting both physical constraints and phonological patterns.

Evidence for koartikulaatio comes from acoustic and articulatory data. Acoustic indicators include formant transitions and spectral changes in vowels adjacent to consonants, as well as predictable shifts in voicing and duration. Articulatory methods such as electromagnetic articulography and ultrasound imaging reveal overlapping gestures directly. The phenomenon is central to theories of speech production and perception, including gestural approaches that model phonemes as coordinated articulatory gestures with varying degrees of overlap.

Understanding koartikulaatio helps explain why speech sounds are not perfectly discrete and how listeners use transitional cues to identify phonemes in continuous speech. It is a universal feature of human languages and a key topic in phonetics and psycholinguistics.