After reading biochemical science here and there and some psycology books, I start to think there is a biochemical base for people's personality. After the first google try, I actually find something with the exact name "Biochemical Personality". They are related to drug or alcohol abuse.
http://www.narcononrehab.com/english/Narconon_Program.html
Long-term alcoholism and drug addiction can cause one's personality to change. This is called the Biochemical Personality. Some of the characteristics are:
- Mood swings
- Unreliable. Unable to finish projects.
- Unexpressed resentment and secret hatreds.
- Dishonesty. Lies to family, friends, employers.
- Withdraws from those who love him. Isolates self.
- May appear chronically depressed.
- May begin stealing from family and friends.
Addicts cannot stop using drugs for two reasons. These are:
- Cravings caused by drug residues which remain in the body.
- The Biochemical Personality caused by drugs and the lifestyle of the addict.