Anosognosia is the name for when individuals are unable to understand or believe they have an illness or health condition. It occurs when your brain is not recognising or responding to the cues it is receiving and typically comes from damage to the frontal lobe. It is most common alongside specific mental health illnesses, including schizophrenia and bipolar disorder, as well as neurological conditions such as dementia. This article will discuss the signs, symptoms and causes of anosognosia, before exploring possible treatment and management options.
Overview: What is anosognosia?
Anosognosia, referred to as a ‘lack of insight’, is when individuals are unable to understand or believe they have an illness or health condition. It occurs when your brain is not recognising or responding to the senses it is receiving from your body, for example, symptoms of your illness.1
It is most common in individuals with severe mental health conditions, however, it can also affect those with other health conditions, such as stroke patients. It is estimated to affect 57% to 98% of individuals with schizophrenia, and around 40% of individuals with bipolar disorder.2
Anosognosia can lead to people not taking their medication or avoiding treatment altogether, as they do not have any awareness of their condition. This can become serious, as their symptoms are likely to get worse and can impact their daily life.
Causes of anosognosia
As humans, we have a mental image of ourselves. We adjust this self-image when certain things happen, for example, after you get a haircut you would expect to look different in the mirror. This is a complex process that occurs in the frontal lobe of our brain and involves organising new information, building a new image, and remembering it.3 Research has shown that damage to this area of the brain can lead to a person losing the ability to update and reflect upon their self-image correctly, for example from schizophrenia or bipolar disorder.4 This is known as anosognosia and is a type of agnosia, where your brain cannot recognise and react to the senses it is receiving.
Anosognosia can leave individuals with an older, past self-image of themselves before their illness or condition began. This feels very real and may lead them to believe their family or friends are lying, causing feelings of anger and untrustworthiness.
Anosognosia is most common alongside specific mental illnesses and neurological conditions (those that affect the brain, spine or nerves), including: 2
However, it can also affect individuals with Huntington’s disease, Parkinson’s disease, and traumatic brain injuries.1
Signs and symptoms of anosognosia
Anosognosia is defined when an individual has one or more of these symptoms: 2
- Unable to recognise and acknowledge that they are suffering from an illness or medical condition
- Unaware of signs and symptoms of the condition that they have
- Unable to connect any symptoms to their particular condition
- Unable to recognise and understand that their condition is serious
- Unable to accept that medical treatment is necessary
These symptoms feel very real for those living with anosognosia, even if you demonstrate real contradicting evidence or challenge them. They are not able to perceive or believe anything different. However, this self-awareness can vary over time. For example, a person may recognise that they have dementia when they first notice symptoms but may lose this insight over time. This can be very difficult for family and friends and can cause individuals to feel angry, stubborn, and may impact their relationships.3
Anosognosia is most common alongside mental illnesses and neurological disorders, however, it may also present with physical symptoms through conditions such as hemiplegia or hemisensory loss. This is when you have paralysis or lose sensation in one side of your body. This typically affects the left-hand side of the body, however, it can also affect the right side. Individuals with anosognosia may be unaware of this problem, even though they cannot use or move one side of their body.5
Visual anosognosia, or Anton’s syndrome, is a very rare condition where an individual lacks insight into their visual difficulties. People with this condition may have severe vision loss, or complete blindness, yet deny these symptoms.6
Management and treatment for anosognosia
There is no specific treatment for anosognosia. This is because it can be caused by several different factors and illnesses. Individuals will likely have a medical team supporting them in different ways, for example, a mental health nurse, neurologist, and specialised doctor.
Some research has indicated that vestibular simulation can help to improve symptoms of anosognosia.7 This approach involves infusing cold or warm water into the ear, which creates a temperature difference that stimulates the nerves inside your ear canal. However, the effects of this seem to be short-term, and only improve symptoms temporarily. 2
Therapy programmes may help an individual to learn positive habits that support their wellbeing and improve symptoms. However, such treatment approaches do not treat the cause of the anosognosia itself.
It can be difficult to approach any treatment for an individual with anosognosia, as they do not believe they have an illness. This can lead to people not wanting to have medication or take part in rehabilitation programmes to help improve the symptoms of their condition.2 Medical providers will also need to speak to family members and friends, as it is possible for individuals with anosognosia to fall over or experience symptoms that they do not bring up to doctors. Doctors can then put precautions in place to ensure the individual is safe and at a reduced risk of injury.
If you have anosognosia, you should listen to your medical team and take their advice. You should not try to manage anosognosia on your own, as there are ways they can help you. As you may struggle to understand or see that you have an illness, it is important to remember that they are experts and will provide you care that you need. You should monitor and follow their treatment plan, take prescribed medication, and look out for any changes in your symptoms.3
How is anosognosia diagnosed?
It can be difficult to diagnose anosognosia, especially if your doctor is unaware that you have an existing condition or illness. This is because people with anosognosia are not aware that they have the condition themselves, and may try to rationally explain their symptoms or signs of illness. Therefore, diagnosis typically requires a physical and neurological examination, asking detailed questions about a patient’s health history, and diagnostic testing or imaging. Individuals must have a specific condition alongside their anosognosia to be diagnosed, and it is most common with mental health illnesses such as bipolar disorder, and neurological conditions like dementia. 2
How can I prevent anosognosia?
You cannot prevent anosognosia and you cannot predict whether an individual will have anosognosia. While there are certain conditions that increase someone’s risk of developing anosognosia, not all individuals will develop symptoms. It is important to look after your health and manage any health conditions you may have with medical professionals.
Who are at risk of anosognosia?
Anosognosia is most common in individuals with severe mental health illnesses, such as bipolar disorder and schizophrenia, or neurological conditions such as Alzheimer’s disease and dementia. It is also a common symptom in patients who have experienced a stroke. Some studies have suggested that older patients with more severe neurological symptoms are at an increased risk of anosognosia.8
How common is anosognosia?
Anosognosia is most common in individuals with severe mental health illnesses and is estimated to affect 57% to 98% of individuals with schizophrenia, and around 40% of individuals with bipolar disorder.6 It is also most common in individuals with dementia or Alzheimer’s disease. It is thought to affect 10% to 18% of individuals that have experienced strokes.9
What can I expect if I have anosognosia?
Symptoms of anosognosia can depend on the underlying condition and can vary from person to person. The main symptom is that individuals are unaware that they are suffering from an illness, and may be unable to recognise symptoms. It can be difficult to look after yourself, and you may feel that you don’t need to take prescribed medication or follow treatment plans. However, it is important to listen to your medical provider, as well as monitor changes in your symptoms closely, even if you feel that they are unrelated or minor. Your doctor is an expert and can help, so you should follow their guidance.
When should I see a doctor?
You should not try to diagnose or manage anosognosia on your own. Diagnosis requires an expert to examine you and your symptoms. It is important to speak to your doctor if you, or someone you know, believe you may have anosognosia. There are many different causes of the condition, and these could worsen over time if you do not receive medical care. Your doctor will also be able to support you and provide you with different treatment options.
Anosognosia is when individuals are unable to understand or believe they have an illness or health condition. It is most common alongside specific mental health illnesses, including schizophrenia and bipolar disorder, as well as neurological conditions such as dementia. It is thought to be caused by damage or changes to the frontal lobe, which affects our abilities to reflect and change our mental images of ourselves. There is no specific treatment for anosognosia, however, vestibular simulation is thought to improve symptoms temporarily. It is important for individuals with anosognosia to continue to follow treatment plans provided by their medical team, as it can make symptoms worsen otherwise.
- Administrator. Anosognosia [Internet]. Treatment Advocacy Center. [cited 2023 Mar 2]. Available from: https://www.treatmentadvocacycenter.org/key-issues/anosognosia
- Acharya AB, Sánchez-Manso JC. Anosognosia. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 [cited 2023 Mar 2]. Available from: http://www.ncbi.nlm.nih.gov/books/NBK513361/
- Anosognosia | nami: national alliance on mental illness [Internet]. [cited 2023 Mar 2]. Available from: https://www.nami.org/About-Mental-Illness/Common-with-Mental-Illness/Anosognosia
- Mondragón JD, Maurits NM, De Deyn PP. Functional neural correlates of anosognosia in mild cognitive impairment and alzheimer’s disease: a systematic review. Neuropsychol Rev [Internet]. 2019 Jun 1 [cited 2023 Mar 2];29(2):139–65. Available from: https://doi.org/10.1007/s11065-019-09410-x
- Team SC. Hemiplegia vs hemiparesis: causes, symptoms, and treatment [Internet]. [cited 2023 Mar 2]. Available from: https://www.spinalcord.com/blog/what-is-the-difference-between-hemiplegia-and-hemiparesis
- Lehrer DS, Lorenz J. Anosognosia in schizophrenia: hidden in plain sight. Innov Clin Neurosci [Internet]. 2014 [cited 2023 Mar 2];11(5–6):10–7. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4140620/
- Gerretsen P, Pothier DD, Falls C, Armstrong M, Balakumar T, Uchida H, et al. Vestibular stimulation improves insight into illness in schizophrenia spectrum disorders. Psychiatry Res [Internet]. 2017 May [cited 2023 Mar 2];251:333–41. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5720160/
- Castrillo Sanz A, Andrés Calvo M, Repiso Gento I, Izquierdo Delgado E, Gutierrez Ríos R, Rodríguez Herrero R, et al. Anosognosia in Alzheimer disease: Prevalence, associated factors, and influence on disease progression. Neurologia. 2016 Jun;31(5):296–304.
- Starkstein SE, Jorge RE, Robinson RG. The frequency, clinical correlates, and mechanism of anosognosia after stroke. Can J Psychiatry [Internet]. 2010 Jun [cited 2023 Mar 2];55(6):355–61. Available from: http://journals.sagepub.com/doi/10.1177/070674371005500604