The causes of most mental disorders are unknown, but the dimensions are becoming more understood.

What we do know about causes:

  • Several factors interact to produce a mental disorder:
    • Individual intrapsychic situation
    • family circumstances
    • social influences
    • biological and genetic factors
  • Trauma and stress can be significant aggravating factors
  • What initiates a disorder is usually different from what perpetuates it. What initiates and perpetuates a disorder may differ from what exacerbates it.
  • A person may have a predisposition, or latent susceptibility, to a disorder which may be activated under certain conditions such as stress.

And, it is important to note:

  • Not all aberrant behavior is a mental disorder. Interactions between various drugs that a person may be taking can cause problem behavior. These interactions can vary by age, sex, with various combinations of prescribed and over-the-counter medications.

Genetic factors in Mental Disorders

Based on studies of twins and adoptees:

  • Disorders with a significant genetic link: Schizophrenia, Bi-polar disorder, Depression
  • Disorders with a weaker genetic link: Panic attack, Obsessive-compulsive disorder

Source:

Essential Psychopathology and Its Treatment, Second Edition by Jerrold S. Maxmen and Nicholas G. Ward, pp 57-79.