Numerous factors have been linked to the development of mental<unk> s. In many<unk>  there is no single accepted or consistent<unk>  A common view is that<unk> s often result from genetic vulnerabilities combining with environmental stressors (Diathesis-stress model). An eclectic or pluralistic mix of models may be used to explain particular<unk> s. The primary paradigm of contemporary mainstream Western psychiatry is said to be the biopsychosocial (BPS) model - incorporating biological, psychological and social factors - although this may not be applied in practice. Biopsychiatry has tended to follow a biomedical model, focusing on "organic" or "hardware" pathology of the brain. Psychoanalytic theories have been popular but are now less so. Evolutionary psychology may be used as an overall explanatory theory. Attachment theory is another kind of evolutionary-psychological approach sometimes applied in the context for mental<unk> s. A distinction is sometimes made between a "medical model" or a "social model" of<unk>  and related disability.
Genetic studies have indicated that genes often play an important role in the development of mental<unk> s, via developmental pathways interacting with environmental factors. The reliable identification of connections between specific genes and specific categories of<unk>  has proven more difficult.
Environmental events surrounding pregnancy and birth have also been implicated. Traumatic brain injury may increase the risk of developing certain mental<unk> s. There have been some tentative inconsistent links found to certain viral infections, to substance misuse, and to general physical health.
Abnormal functioning of neurotransmitter systems has been implicated, including serotonin, norepinephrine, dopamine and glutamate systems. Differences have also been found in the size or activity of certain brains regions in some<unk> . Psychological mechanisms have also been implicated, such as cognitive and emotional processes, personality, temperament and coping style.
Social influences have been found to be important, including abuse, bullying and other negative or stressful life experiences. The specific risks and pathways to particular<unk> s are less clear, however. Aspects of the wider community have also been implicated, including employment problems, socioeconomic inequality, lack of social cohesion, problems linked to migration, and features of particular societies and cultures.
Mental disorder causes
Mental disorder risk factors
Dementia causes
Causes of mental disorders
Cancer causes
Traumatic brain injury risk factors
Personality disorder causes
Coronary heart disease causes