A syndrome characterized by clinically significant disturbance in cognition, emotional regulation, or behaviour that reflects a dysfunction in the psychological, biological, or developmental processes underlying mental functioning. Mental disorders are usually associated with distress or disability in social, occupational, or other areas of functioning. According to ICD-10, a mental disorder is a clinically recognizable collection of symptoms or behaviour associated in most cases with distress or interference with personal functions. A deviant pattern of behaviour, whether political, religious, or sexual, or a conflict between an individual and society is not a mental disorder unless it is symptomatic of a dysfunction in the individual. --Oxford Dictionary of Psychology, 4th edition.