For the Brainwave festival, the Rubin Museum demonstrates the cerebellum's higher functions with heady talks, performances, and screenings. Last month, tantric Dutchman Wim Hof endured 82 minutes in an ice bath outside the museum, and Lou Reed guided meditation. In the coming months, tripped-out anatomist of energy Alex Grey discusses his paintings; a neurologist dissects The Tibetan Book of the Dead; and two brothers perform Hindu classical music — all in celebration of the three pounds of gray matter that grant us experience.