Possible Clues:

• Reduced pains, yes, if one isn't functioning?
• Nerve impulse transmission site
• Part of a thought process?
• Sleeps during Yes composition, 'Nervous Connection'
• Firing point, of a sort
• EPNS, say, could form connection between nerve cells
• Where two nerve cells meet
• Transmission site
• Nervous system junction
• Whatever in clairvoyance's recalled mental connection?