Causes

What are the causes of mental illness?

In spite of the research in this field, we still don’t know the cause of every mental illness. However, we do know that there are triggers: often painful events that can provoke the onset of an illness, for example the loss of a loved one, a divorce, the loss of a job, an accident or a serious illness.

Furthermore, we now know that there is a biological origin to certain illnesses. Thanks to modern technology, we are increasingly able to understand the way the brain functions. Certain substances identified by researchers, such as serotonin (a neurotransmitter), play an important role in the development of mental illnesses like depression.

Research indicates that mental illnesses result from a complex interaction of genetic, biological, and personality traits and the social environment. This is what’s known as the “bio-psycho-social” model. This model underlines the constant interaction between the biological, psychological and social aspects of illnesses and rejects reducing an illness to a single aspect of human beings, to the benefit of the person who is ill.

On the other hand, the brain is the final common site for the control of behaviour, thought, mood and anxiety. However, the links between specific cerebral dysfunctions and specific mental illnesses are not entirely known (Kessler, R.C. and Ahangang, Z. (1999), paraphrased in Health Canada et al. (2002). A Report on Mental Illness in Canada, Ottawa, p. 22) which prompted Health Canada to point out that “It is important not to over-interpret the available evidence about the role of either genetic or environmental factors in causing mental illnesses as much more research is needed to fully understand the causes of mental illness.” (Health Canada et al. (2002), A Report on Mental Illnesses in Canada, p. 22.)

Corroborating this line of thought, researchers from the Régie régionale de Montréal-Centre add that “The chains of causality of mental disorders are complex. In spite of this limit to our knowledge, it is possible to reduce the incidence of mental disorders by acting, before they appear, on the biological, psychosocial or physical factors known for their causal role. Prevention attacks both risk factors and pathogenic conditions.” (Régie régionale de la santé et des services sociaux de Montréal-Centre. (2001) Rapport annuel 2001 sur la santé de la population : Garder notre monde en santé, un nouvel éclairage sur la santé des adultes montréalais, p. 64.)