I'm sure that many people have noticed little quirks of the Heroes characters, which, in real life, might indicate odd psychological problems.
* Niki = MPD/Multiple Personality Disorder, Alcoholism
* Sylar = OCD/Obssessive Compulsive Disorder
* Claire = Self-Harming Behaviors
* Isaac = Multiple Addictions
* Peter = Self Esteem issues, leading to Self-Sabotage Syndrome
* Nathan = Fear of Intimacy and Relationships, emotional detachment
* Hiro = General Reality Perception issues
* Matt = Self Esteem issues, Self-Fullfilling (low achievement) behaviors
* Mohinder = Self-Esteem issues (2nd Child Syndrome) and unresolved Childhood Trauma surrounding the loss of his sister.
Most exhibit signs and behaviors related to low self-esteem, narcissism, some anti-social quirks and other behaviors that people with Mental Illness or Mental Disorders display.
Does it make you think, "Hmmm"?
I'm sure I will return to this topic often!