noun
The anatomical organ; common in medical, scientific, and everyday contexts when speaking specifically about the brain.
事故で脳に損傷を受けた。
He suffered damage to his brain in the accident.
人間の脳は大量の情報を処理している。
The human brain processes a huge amount of information.
noun
mind; brains; mental faculties
Refers to the brain as the seat of thought or mental activity. 頭 is often the more everyday word for intelligence or thinking, while 脳 sounds more biological or analytical.
長時間の会議で脳が疲れた。
My brain is tired from the long meeting.
パズルは脳を鍛えるいい練習になる。
Puzzles are good practice for training the brain.