More physical / visceral than
大脑 (dànǎo, 'cerebrum') or
头脑 (tóunǎo, 'mind').
脑髓 emphasizes the soft tissue itself — used in anatomy, horror writing, and food contexts (
脑髓菜 brain dishes in some Chinese cuisines). Lu Xun used the word repeatedly in essays attacking superstition and 'rotten brains.'
