Although coarticulatory variation is largely systematic, and serves as useful information for listeners, such variation is nonetheless linked to sound change. This article explores the articulatory and perceptual interactions between a coarticulatory source and its effects, and how these interactions likely contribute to change. The focus is on the historical change VN (phonetically, ṼN) > Ṽ, but with more general attention to how a gesture associated with a source segment comes to be reinterpreted as distinctively, rather than coarticulatorily, associated with a nearby vowel or consonant. Two synchronic factors are hypothesized to contribute to reinterpretation: (i) articulatory covariation between the duration of the coarticulatory source (here, N) and the temporal extent of its effects (Ṽ), and (ii) perceived equivalence between source and effect. Experimental support for both hypotheses is provided. Additionally, the experimental data are linked to the historical situation by showing that the contextual conditions that trigger (i) and (ii) parallel the conditions that historically influence phonologization of vowel nasalization.