Puzzled by Chief Bromden

This past reading has given the reader many more clues to Chief Bromden's psychological disorder, a fact which has previously puzzled me greatly. Bromden seems incredibly observant, insightful and intelligent, and to me did not seem to be a candidate for "more than two hundred shock treatments" or permanent residency at a mental facility (69). However, the new facts about Bromden's past reveals, in part, some of the problems that caused Bromden's mental distress. Bromden talks extensively about the "fog" in this section, something that we learn is induced not by medicine and shock treatments alone but also by choice. Bromden chose to hide in a void of apathy and disinterest under the guise of deafness rather than become involved in the lives of the other inmates, since he reveals that he is a very empathetic individual. Although a lack of empathy can lead to psychopathy or sadism, which can clearly harm society, Bromden's issue seems to cause pain to only himself. In addition to his overly empathic nature, Bromden also seems to be suffering from Posttraumatic Stress Disorder, which my psychology book defines as a delayed stress reaction to in which an individual involuntarily reexperiences emotional, cognitive, and behavioral aspects of past trauma.  Although the Bromden does not directly state his involvement in the Second World War, the reader can infer this fact since he references a battle in Anzio, where he "saw a buddy of [his] tied to a tree fifty years away...screaming for water, his face blistered in the sun," yet he was unable to help due to the enemy soldiers stationed nearby (137). The disturbing scene described and the associated guilt would haunt any sane person, and Bromden's extreme empathy could only hinder his recovery from that incident. Despite this, PTSD is not an incredibly serious mental disease to treat. It effects thousands to soldiers and catastrophe survivors, and to me certainly does not require the intense and long-lasting "care" Bromden has endured. Is there more to Bromden's mental state which Kesey has yet to reveal which would explain his "Chronic" status at the ward?

Chief Bromden looking sad in the film One Flew Over the Cuckoo's Nest