Coma vs brain death

I personally found it really interesting to learn the differentiation between a coma and brain death. The term brain death was completely new to me when it was presented in class. Brain death is irreversible absence of clinical brain function, including brainstem reflexes. This state cannot be recovered from. However, a coma is a state of unresponsiveness and lack of awareness which lasts for longer than one hour. Unlike brain death, it is possible to come out of a coma and regain full consciousness again.  Interestingly, there are a few common states of consciousness a person may experience once they wake up from the coma.

The first is post-coma unresponsiveness, this happens when a person is able to move their eyes but show no other signs of consciousness. During this stage, a persons sleep cycle should be normal and they are able to open and close their eyes as well as being able to react to loud noises. These happen as a result of involuntary, autonomic responses in the body. Once an individual regains purposeful behaviour they are then in a conscious state. A big question that many loved ones of people in comas ask is can they hear you? It is believed that although a person in a coma cannot respond to you, they can still hear you. Brain scans show that areas of the brain associated with retrieving long term memory and understanding language, increase in activity levels when a family member speaks to them (Czyzewsk, 2017). This research can give a piece of hope to anyone waiting for a family member to wake up, that their loved one is still there and listening.

Czyzewski, A. and Kostek, B., (2017). Assessment of hearing in coma patients employing auditory brainstem response, electroencephalography, and eye-gaze-tracking. The Journal of the Acoustical Society of America, 141(5), pp.3903-3904.