A 40-year-old man with acute right-sided facial weakness also reports diminished taste sensation on the anterior two-thirds of the tongue on the same side. Loss of lacrimation is noted. The lesion involves the facial nerve proximal to the geniculate ganglion. Taste fibres from this region synapse first in which structure?
- A Ventral posteromedial nucleus of the thalamus
- B Nucleus of the tractus solitarius ✓
- C Geniculate ganglion
- D Superior salivatory nucleus
Correct answer: B. Nucleus of the tractus solitarius
Explanation
Taste afferents from the anterior two-thirds travel in the chorda tympani, with cell bodies in the geniculate ganglion, then enter the nervus intermedius and terminate centrally in the gustatory division of the nucleus tractus solitarius in the medulla. From there, second-order fibres project via the central tegmental tract to the contralateral ventral posteromedial thalamic nucleus. The geniculate ganglion contains only primary sensory neurons, not the central synapse.
Reference: Gray's Anatomy for Students, 4th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.