Fig. 1.

Median and vagus nerve afferent projections to the primary somatosensory cortex. Median nerve fibres travel rostrally to synapse in several thalamic nuclei, including the ventral-posterolateral (VPL) nucleus. In comparison, afferents of the vagus nerve project primarily to the nucleus tractus solitarius (NTS) and parabrachial nuclei, and subsequently to the ventral-posteromedial (VPM) nucleus of the thalamus. After synapsing in their respective thalamic nuclei, nerves from both the median and vagus nerves course through the corona radiata to their respective topographic targets within the primary somatosensory cortex (S1).