system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Pain insensitive structure
assistant
The correct answer is  The cranium, brain parenchyma, ependymal lining of the ventricles, and choroid plexus are all pain insensitive Ref Harrison20th edition pg 2345