There was a very excellent episode of the podcast Radiolab. I just listened to that covered the subject. It’s called “Black Box”.
It discusses three topics, but the first is about the advent of anesthesia. It briefly describes what surgeries were like before anesthesia was developed. It was really interesting to hear that operation theaters were placed in hospitals in such a way as to minimize the sound of screams throughout the rest of the hospital.
From there, it discusses what a mystery it was to medicine what actually took place in the brain when patient was knocked out from anesthesia. There were even instances where, although the physical body was completely disabled, consciousness would return to the patient and they would be conscious through the surgery.
Fortunately, we now have better technology to monitor brain activity while people are under.
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