Anosognosia is also called lack of awareness or lack of insight. When we talk about anosognosia in mental illness, we mean that someone is unaware of their own mental health condition or that they cannot perceive their condition accurately. The word itself comes from the Greek word for disease (nosos) and knowledge (gnosis) and literally means to not know a disease.
Anosognosia is a common symptom of schizophrenia and bipolar disorder with psychotic features. It affects approximately 50 percent of individuals with schizophrenia and 40 percent of individuals with bipolar disorder. It can also accompany illnesses such as major depression with psychotic features, and is the most common reason that individuals with schizophrenia and bipolar do not take their medications.
How does Anosognosia develop?
Update our mental image of ourselves over time is a complicated process. It requires the brain frontal lobe to organize new information, develop a revised self-image. Brain imaging studies have shown that this crucial area of the brain can be damaged, losing or impairing the ability to update one’s self-image.
Without an update, the old self-image from before the illness started remains and since these perceptions feel accurate, those with anosognosia conclude that others are lying or making a mistake. This can lead to confusion, frustration and/or anger. The misperceptions often cause conflicts with others and increased anxiety. Lack of insight also typically leads to an avoidance of treatment and is one of the most common reasons for people who stop taking their medications.