Tongue and lip constrictions shift vocal resonances mostly near their nodes, not antinodes.

Evidence

We have seen that given a thin constriction somewhere, some modes will be lowered in frequency—namely, the ones that had a node at or near the constriction. Other modes with antinodes very close to the constriction will be relatively unaffected. It is clear that the net effect will be to move some resonances down, and others very little. — Eric J. Heller, Why You Hear What You Hear- An…, 1644

Categorization

• XREF: Connects to how vowel formants change as the tongue shapes the vocal tract—relevant to the physics of speech produced by articulatory movement.