There many, many mental illnesses out there. My aunt has ADHD, a mental disorder that renders her incapable of concentrating or staying in one spot for awhile. My father went to college with a boy who had Tourette's Syndrome, a mental disorder that forces the victim to shout out words for no reason whatsoever. A boy at my high school has ODD, a disorder that makes him of a more aggressive, bullying type. If you're talking about insanity, then you may see MANY different characteristics in different people. If you suspect you have ANY mental disorders, then talk to a psycologist. Remember that it's their job to find out what's wrong, and it's also their job to listen. You don't have to tell anybody, and nobody will ever know.
Mental problems are chemical imbalances in the brain. Meaning the brain does not function properly. It can depend on the type of problem, if you Google some case studies you may understand more.
Not all mental problems are caused by a chemical imbalance. It could just be a psychological issue you have like stuttering or anxiety which a lot of times is due to unresolved stress and lack of coping skills. Simple things like changing your diet (you may be lacking in some essential vitamins and nutrients. Also, a healthy lifestyle like exercise and drinking water, to bring out a more positive, challenging and rewarding self can cure you of many ailments. For example, if you are a pessimist (you most likely don't exercise), you may become depressed. It is all a matter of perspective, how you view life. If you look for the good in things, you'll surely find them and vice versa.
Symptoms of mental illnesses vary from hearing voices, delusion's, obsessive behavior, odd behavior, depression, extreme low self esteem, lack of hygiene, repeating words or sentences, lack of common sense and many other not "normal" symptoms.
It always depends on what kind, what age, and position you're in.
If your "Mental Illness" is something that causes different Behavior or embarrassing actions.. Then of coarse, you will be most likely Ridiculed by "Normal People". Personally, I think it's fine to have a mental illness, it makes you who you are, and defines part of your Natural "Character".
Having a mental illness is common with certain age groups. 13-17 a lot of times have "Dual-Personalilties" or being "Bipolar". But this is Irrelevant to the point of Severeness or Insanity.
Mental Illnesses come in many different "Shapes and Sizes" but most can be bad. Many people who suffer from Mental Illnesses don't even realise it. Many can become more Unaware of this and become Mentally Unstable.
But I'd rather answer this question in a more Specific way.. So if you would mind; Putting this in a more Specific question?
self harm, suicide, drug abuse, risky behaviour, alcohol dependancy, etc
eating disorders (anorexia, bulimia), schizophrenia, anxiety, bipolar mood disorder, depression
because it ruins people's lives, costs them their jobs, costs society many very productive workers, costs society for treatments (or non-treatment), etc.
which one?
Sociopath.
DSM is a book of mental illness symptoms and diagnosis and it is used by mental health professionals to diagnose such illnesses
A symptom is a physical or mental manifestation that indicates the presence of a condition/illness.
Munchausen syndrome - a type of factitious disorder, or mental illness, in which a person repeatedly acts as if he or she has a physical or mental disorder when, in truth, he or she has caused the symptoms.
anorexia nervosa and bulimia which are opposite when it comes to signs and symptoms
Mental illnesses are mostly genetic. If there are no genetic markers then the chances of someone experiencing a mental illness sometime in their lives is not likely. If symptoms are present a doctor should be contacted immediately.
Mental illness, a panic attack,
Sinusitis is not caused by mental illness. Mental illness can be caused by sinusitis infection.
not guilty by reason of mental illness
Mental illness predates recorded history.
A person exhibiting these symptoms does not necessarily have any mental illness but they would have to go to a mental health professional for a diagnosis.
Mental illness is both conscious and unconscious. A person who is experiencing psychosis is typically living in an altered state of reality. A person with multiple personality disorder and schizophrenia is living in and out of a state of reality consciousness. But even a person living in a psychosis may not be aware of their illness. The symptoms are never as clear as physical illness.