https://thebrainissocool.com/2026/05/24/howard-fields-1939-2026/The brain is sooooo cool!en2026-05-24T19:55:23+00:00Howard Fields (1939-2026)OFF cell; OFF cells; raphe magnus; medullary raphe; pain modulationhttps://thebrainissocool.com/wp-content/uploads/2026/05/image-2.png?w=99