Yes, ENCEPHALON is a Scrabble word!

Letter values in Scrabble US: E 1, N 1, C 3, E 1, P 3, H 4, A 1, L 1, O 1, N 1.

Is it a valid word?

ENCEPHALON is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

that part of the central nervous system that includes all the higher nervous centers; enclosed within the skull; continuous with the spinal cord