Face, voice, hearing, and posture symptoms cluster together and get treated as separate problems.

Rosenberg's most practical extension of Porges: social engagement isn't a vagus trick, it's a five-cranial-nerve system — "the ventral branch of the vagus nerve (cranial nerve X), and pathways within cranial nerves V, VII, IX, and XI" — behaving as one coupled unit. The coupling is what makes his testing work: a trapezius squeeze testing CN XI reads out ventral vagal function, and fixing one nerve lifts the other four. One intervention point moves the whole system, which is why a throat test can predict facial-nerve function and a neck exercise can change a face.