People with mental illness may experience disturbing thoughts, feelings or behaviors that are different from the norm. These disorders can interfere with everyday life and make it hard to go to school, work or carry out daily routines. They can also make it difficult to form and maintain relationships and to perform well in other areas of life, such as achieving academic success or developing a career (Kessler et al, 2005b). The presence of a disorder is not always clear-cut and can be a matter of degree rather than clear boundaries between normal and abnormal behavior.
Mental illnesses are often influenced by both genetic and environmental factors. Many of these conditions are associated with changes or imbalances in neurotransmitters, the chemical messengers that brain cells use to communicate with one another. In addition, certain genes appear to be linked to specific disorders. Mental illnesses are primarily a medical condition and, like other medical conditions, they can be diagnosed and treated by physicians or psychologists.
It was once thought that mental illness was caused by demons and that it was a sign of sin or moral failing. People who suffered from psychological illness were believed to be infected with a demon, and treatment included whipping, bloodletting, purges and even trepanation (cutting a hole in the skull).
In the 17th century, a movement toward Enlightenment led to a recognition that madness was organic and not related to soul or moral responsibility. This was followed by the gradual development of asylums throughout the world. Treatment was generally harsh and inhumane, but by the middle of the 19th century, a movement toward deinstitutionalization began. Psychiatric medication also gradually changed, with the introduction of lithium and antidepressants. Benzodiazepines were also widely used, until dependency problems curtailed their popularity.
A number of psychological disorders are characterized by fear or anxiety. Some of these include generalized anxiety disorder, phobias and post-traumatic stress disorder. For example, social anxiety disorder is characterized by an intense fear of being embarrassed or humiliated in social situations, which can significantly impact on educational and occupational functioning.
Disturbances in perception and thinking, including hallucinations and delusions, are associated with schizophrenia, schizoaffective disorder and a few other psychotic disorders. Schizophrenia is a complex disorder that involves both positive and negative symptoms, and some people have features of both schizophrenia and affective disorders (schizotypy).
Anxiety disorders can be triggered by many factors, such as an overwhelming or frightening situation or the loss of a loved one. They can be characterized by anxiety, irritability, a depressed mood and difficulty with concentration, among other symptoms.
Some people with a mental illness can improve their symptoms with psychotherapy, which can help them learn how to manage the illness and change negative thought and behavior patterns. Other people may find relief from medications, such as antidepressants and antipsychotics, which can alter the way chemicals are used in the brain. Medication can sometimes be combined with psychotherapy, and it is important to take any medication only as directed by a healthcare provider.