Chapter 4 in general talks about our sense organs and how our brain interprets the messages from them. I found the part about how our body senses touch and pain particularly interesting. Did you know that the information about touch travels more quickly to the brain than that of pain?
There was also a portion explaining how some people are insensitive to pain. Although it sounds cool at first, such people might break a bone and not be aware of it. That is definitely scary! Our textbook gives an example about a girl, Ashlyn Blocker who has congenital insensitivity to pain with anhidrosis. It says that she should be monitored constantly because she could eat food that is extremely hot without any hesitation. (This video shows that how Ashlyn's condition could be used for pain management research.)
This example particularly interested me because I remember watching a Grey's Anatomy episode where they show a little girl who claims to be a super hero because she cannot feel the pain even when hit in her stomach with a baseball bat. It also looked like a good example of occam's razor, one of the six principles of scientific thinking.
The textbook says that blind people are more sensitive to touch inputs; it makes me wonder: so when a sense organ fails to function, do other sense organs always work "overtime"? What would possibly make a good balance for Ashlyn's condition?