An innovative surgical training model has been developed called the bionic humanoid, containing certain artificial tissues with lifelike textures. The eye surgery model recreates a part of a membrane that's just 3 micrometers thick. Surgeons can practice a difficult surgery that involves peeling it away. The brain surgery model replicates complex structures within the skull to help surgeons practice removing tumors through the nostrils. The models could transform training for novice doctors.