The Nature article's abstract says: > neurons in the vagal ganglia and brainstem are activated via the gut–brain axis to create preference for sugar Wikipedia

The Nature article's abstract says: > neurons in the vagal ganglia and brainstem are activated via the gut–brain axis to create preference for sugar Wikipedia says: > Broadly defined, the gut–brain axis includes the central nervous system, neuroendocrine and neuroimmune systems, including the hypothalamic–pituitary–adrenal axis (HPA axis), sympathetic and parasympathetic arms of the autonomic nervous system, including the enteric nervous system and the vagus nerve, and the gut microbiota.[1] Having access to only the article's abstract, it's hard to know how or if the microbiota (bacteria, etc.) are involved in nerve activation. E.g., are the neurons activated directly by glucose, or are they activated by some chemical that the bacteria produce in the presence or absense of glucose? [1] https://en.wikipedia.org/wiki/Gut%E2%80%93brain_axis https://en.wikipedia.org/wiki/Gut%E2%80%93brain_axis