Case for Holden and Bipolar

1) His obvious depressive symptoms
- Especially near the end of the book, he openly states that he's depressed (sadness)
- Insomnia
- From his venture to Agerstown he does not eat for a full day - until breakfast with the nuns (Lack of appetite, appetite fluctuations)
- Holden does not follow through with his intentions or fails to act upon them entirely (indecisiveness)
- At Pencey Prep Holden does not perform according to his potential, because he doesn't want to (lack of motivation)

there are plenty more - I found a link to the beck depression inventory here I think holden would score pretty high.

2) Manic episodes: The one I have in mind is the conversation he has with Sally Hayze at the ice rink diner - his sudden desire to marry/run away with her. His infatuation with a girl he does not particularly admire isn't so unusual, but the sudden onset is a bit disturbing. Other episodes could include breaking the windows of his garage, and his sudden decision to travel to New York - obviously not very well thought out.

I'd say it's pretty clear. Get that kid on some mood stabilizers.