Around the same time, over at Trinity College, Cambridge, the physiologist John Newport Langley was using nicotine to map out the autonomic nervous system (ANS), responsible for regulating heart rate, blood pressure, respiration, sexual arousal and digestion, when he discovered something unexpected.25 Surveying the thousands of ganglia that line the stomach, small and large intestines, pancreas and gallbladder, he observed that these seemed to function unassisted.
