The Diving Butterfly

a) What is 'Locked-in syndrome'? Why would one consider Bauby's condition a prison? What is the significance of The Butterfly?
Locked-in syndrome is a condtiton where you cannot talk, move or express yourself at all. One would consider this a prison because you can't even talk to any body, can't get any thing you want and are absolutely helpless. The butterfly is significant because it symbolyses freedom, something he cannot attain.
b) What was Bauby's "frightening truth'?
His frightening truth is the fact that he'll never be able to do any thing at all without help for the rest of his life. He will be partially paralyzed forever.
c) In your opinion, how do you think Bauby should measure progress? Why do you think Bauby ends the chapter "Prayer" with the phrase, "I set out for the kingdom of slumber with this wonderful talisman, which shields me from all harm."
He should most likely measyre progress in very small steps, otherwise any progress could be missed and he would become disheartened. I think he ends this way because he is trying to remain opptomistic, and not give into the terror of an abyss.