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In his article, “Feeding, emotion and the brain stem: The interesting case of the mesencephalic trigeminal nucleus,” Turnbull (2026. Feeding, emotion, and the brain stem: The interesting case of the mesencephalic trigeminal nucleus. Brain Sciences, 16(1), 61) asserts that upper brain stem structures contribute fundamentally to consciousness, challenging the long-held understanding in neuropsychology that consciousness is strictly cortical. He focuses on the mesencephalic trigeminal nucleus, notable for its integration of sensory and motor functions of the oral cavity. Turnbull presents a credible argument linking this nucleus to both interoceptive processes and affective experience. Due to its proximity to the periaqueductal gray (PAG), a key substrate of felt experience, he raises the possibility of non-synaptic communication, including volume transmission, between the PAG and the nucleus. This, then, could explain feelings connected to oral activities – pleasurable ones related to feeding and kissing, as well as rage and frustration, expressed through biting. Brain stem structures develop in utero and integrate visceral, motor and affective systems. Important questions remain about how and when the links among these structures form in the growing fetus.