The time to initiate naming a printed target word is reduced when preceded by an identical masked prime (match prime) or by one that has the same initial letter (onset prime) compared to an all letter different control. Masked priming has been examined using vocal response time but offers an opportunity to examine speech production dynamics before the onset of speech acoustics. We tracked tongue-dorsum, tongue-tip and lip motion from four participants pronouncing 19 targets in match, onset and unrelated control prime conditions. Control primes were selected so their articulation involved a different tongue gesture than the target. Prime influence was measured by tongue-dorsum height at gestural onset and peak velocity of the subsequent gesture. Results showed that relative to targets in the match condition, control targets had a significantly different tongue dorsum height and the peak velocity was greater when the subsequent gesture was achieved.