Brainstem activation from sustained vowel phonation

Motivation: The brainstem plays an essential role in relaying motor commands to the speech production apparatus with separate cranial nerve nuclei controlling the functions of the lips, jaw, tongue, soft palate, and larynx. Goal(s): To localize some of these nuclei using BOLD imaging. Approach: In the block design fMRI experiment, we employed simultaneous multi-slice EPI with high acceleration factor to image the brain stem. The task involved targeting cranial nerves V, VII, and XII by comparing two vowels [ɑ] and [i]. Results: We observed activation near the Hypoglossal nucleus for [ɑ]>[i] and activation near the Trigeminal nucleus for [i]>[a].. Impact: Our results demonstrate the feasibility of localizing brainstem nucleus with fast simultaneous multi-slice EPI and sustained vowel phonation tasks.