As observed at the outset, the sole concern to be decided is no matter if Dr. Deisher's idea of vaccine-triggered autism satisfies petitioners' stress in this case under Althen Prong One. Respondent disagrees that petitioners have recognized Prong One. Moreover, postmortem experiments cited by respondent do not guidance Dr. Burkhard's testimony that autistic brains display "prevalent and diffuse dysfunction of myelin." Resp. Tr. 371.