How anesthesia changes the brain ^{CEFR A2}

A university team led by Janna Helfrich studied the brain under anesthesia. They recorded brain activity from patients who received propofol. The researchers used electroencephalography (EEG) with electrodes across the head to collect signals from front, sides and back instead of only the front.

They compared these recordings with deep sleep, REM sleep, coma and normal wakefulness. The results show that anesthesia is not simply deep sleep: sometimes it looks like sleep, sometimes like coma, and sometimes it is different. The study says deep anesthesia can cause problems after surgery, especially for older people and those with existing health conditions. The researchers hope better brain monitoring will reduce these problems.