SCHIZOPHRENIA:
Do you Hear What I Hear?

MULTIPLE PERSONALITY DISORDER:
We Three Queens Disoriented Are

DEMENTIA:
I Think I'll Be Home for Christmas

NARCISSISTIC:
Hark the Herald Angels Sing About Me

MANIC:
Deck the Halls and Walls and House and Lawn and Streets and Stores and Office and Town and Cars and Busses and Trucks and Trees and Fire Hydrants and...

PARANOID:
Santa Claus is Coming to Get Me

PERSONALITY DISORDER:
You Better Watch Out, I'm Gonna Cry, I'm Gonna Pout, Maybe I'll tell you Why

DEPRESSION:
Silent Anedonia, Holy Anhedonia, All is Flat, All is Lonely

OBSESSIVE-COMPULSIVE DISORDER: 

Jingle Bell, Jingle Bell, Jingle Bell Rock, Jingle Bell, Jingle Bell, Jingle Bell Rock, Jingle Bell, Jingle Bell, Jingle Bell Rock, Jingle Bell, Jingle Bell, Jingle Bell Rock, Jingle Bell, Jingle Bell, Jingle Bell Rock, Jingle Bell, Jingle Bell, Jingle Bell Rock, Jingle Bell, Jingle Bell, Jingle Bell Rock, Jingle Bell, Jingle Bell, Jingle Bell Rock, Jingle Bell, Jingle Bell, Jingle Bell Rock, Jingle Bell, Jingle Bell, Jingle Bell Rock, Jingle Bell, Jingle Bell, Jingle Bell Rock, Jingle Bell, Jingle Bell, Jingle Bell Rock, Jingle Bell, Jingle Bell, Jingle Bell Rock, Jingle Bell, Jingle Bell, Jingle Bell Rock, Jingle Bell, Jingle Bell, Jingle Bell Rock, Jingle Bell, Jingle Bell, Jingle Bell Rock, Jingle Bell, Jingle Bell, Jingle Bell Rock, Jingle Bell, Jingle Bell, Jingle Bell Rock, Jingle Bell, Jingle Bell, Jingle Bell Rock, Jingle Bell, Jingle Bell, Jingle
Bell Rock............(better start again)

PASSIVE-AGGRESSIVE PERSONALITY:
On the First Day of Christmas My True Love Gave to Me (and then took it all away)

BORDERLINE PERSONALITY DISORDER:
Thoughts of Roasting on an Open Fire