Anosognosia: when we do not perceive our disorders.

We explain the causes, symptoms and possible treatments for this disorder.

"Pedro suffered a stroke a month ago. Due to this Cardiovascular accident, he suffered a hemiplegia that has left him paralyzed on the left side of his body, unable to move his limbs. During a scheduled visit to his doctor, he underwent a complete examination and it became apparent that Pedro was still unable to move his left arm and leg. However, Pedro indicates that he does not have any physical problems and that he moves normally, stating with full conviction that he has in fact been doing all the movements indicated to him correctly during the examination".

This case reflects that Pedro has the belief that his arm is moving normally, there being a clear difference between what he thinks he is doing and his actual performance. This is a case of a phenomenon known as anosognosia..

What is anosognosia?

We understand anosognosia to be a special subtype of agnosia, in which the patient is unable to recognize the existence of a deficit in functioning even though it may be evident to others. It is a lack of awareness of illness limited to the recognition of one's own deficit, and the same individual may be able to detect the same problem in others.

Anosognosia is not a disorder in itself, but is categorized as a symptom, as it it appears only in association with the existence of a disorder and informs us of its existence..

Although the study of anosognosia is very common in the treatment of hemiplegia, anosognosia is not limited to this disorder alone, but can arise from a large number of brain lesions that are not necessarily associated only with the problem of the motor system, but also with the perceptual system (it is typical to observe its presence in patients with cortical blindness) or other disorders, including psychiatric disorders.

Detecting anosognosia

In order to diagnose anosognosia it is necessary, in addition to the presence of unawareness of the deficit, that it is denied by the patient, the fact that the deficit is evident in a neuropsychological evaluation, that it is recognized by family and relatives, and that it involves a clinically significant interference in the patient's life.

When assessing this phenomenon, it is necessary to distinguish between when the patient really presents anosognosia and when he or she is in denial of his or her problems as a coping strategy in the face of his or her loss. Despite this complication, some specific assessment instruments have been developed to evaluate anosognosia, asking the patient to rate which ask for assessment of ability and difficulty in performing specific tasks.

Anosognosia is not an all-or-nothing phenomenon, and cases can be observed in which the disorder is not recognized at any time but also others in which patients recognize the existence of a problem after deficits are demonstrated to them.

Why does it occur? Possible causes

Since this phenomenon was named anosognosia by Babinski in 1914, attempts have been made to explain why this symptom occurs.There are multiple theories in this regard. The explanatory proposals are varied, focusing on the existence of neurological or neuropsychological problems.

An example of this is the theory called Dissociable Interactions and Conscious Experience of Schachteraccording to which there is an interaction between the systems in charge of the conscious experience and those of the systems in charge of the deficient function, which in the event of a lesion or malfunction would cease to integrate the information correctly, producing a conscious experience of action or functionality when this does not occur in the affected system.

Despite these generalities, the specific cause of anosognosia will depend on the type and location of the lesion and the problem causing it. and the problem that causes it.

Some conditions in which anosognosia occurs

As already mentioned, anosognosia is a symptom present in a wide range of problems. Some of them are the following:

1. hemiplegia

One of the most frequent disorders in which its appearance is more frequent.. In these cases, the patient usually believes that he/she is making movements that in reality he/she is not making, and in fact he/she has the conscious experience of making them.

2. Cortical blindness

Many patients who have destroyed the occipital area of the brain or the connections between it and the visual pathways (which prevents visual perception), insist that they are able to see normally, making exhaustive descriptions of what they think they see. Anosognosia is also present in these cases.

3. Lateral hemineglect

In this disorder although the subject perceives the totality of the perceptual field, he/she neglects or does not attend to one of the visual hemifields, not attending to the part or the other hemifield.The subject does not pay attention to the part opposite to the hemisphere in which he/she suffers the lesion. It is clearly visible when he is asked to make copies of drawings: in these cases he only draws one of the halves and "forgets" to fill in the other part located on the other side of an imaginary vertical line. In this context, the patient is often unaware of his problem, presenting anosognosia.

4. Dementia

Although in the initial stages of dementia the patient is usually aware of the presence of his various problems, this awareness does not occur in all cases, this awareness does not occur in all cases or in all dementias.. Moreover, as the disease progresses and the degenerative process takes its course, the individual tends to cease to be aware of them.

5. Schizophrenia

In some subtypes of schizophrenia, such as disorganized and catatonic, and especially during the acute phases of the disorder, the patient often does not perceive the presence of his or her own difficulties, as for example in the case of disorganized, tangential, derailed or incoherent language use.

Other

Apart from those mentioned here, there is a very high number of mental and neurological disorders that present anosognosia, being an important symptom to be taken into account in the treatment of various problems.

Effects of this symptom

It must be taken into account that the presence of this problem can entail serious dangers.

The presence of anosognosia makes it difficult to follow a treatment or to rehabilitate the disorder that causes it. of the disorder that causes it. It should be taken into account that for a patient to become involved in his or her recovery, he or she must be motivated to do so, which is difficult if he or she is unaware of the presence of symptomatology. Thus, patients with anosognosia often underestimate or even deny the need for treatment, making it difficult for them to adhere to the established prescriptions.

In addition, lack of knowledge of the problem may lead the subject to perform actions that may endanger his integrity and/or that of third parties. and/or that of third parties. An example of this could be an individual with lateral hemineglect (subjects who only attend to one hemifield, being unable to see the left or right side of things for example) or with cortical blindness who truly believes to have his abilities preserved and functional, who decides to take the car and drive.

Treatment of anosognosia

The treatment of anosognosia itself is complex.. In general, the symptom improves with treatment of the underlying cause of its onset, be it a mental or neurological disorder. However, at the clinical level, confrontational strategies are employed.

In this sense, the confrontation of the existence of deficits must be progressive, introducing little by little the idea of their existence. It is important not only to show the presence of deficits, but also the difficulties they imply in daily life.

Bibliographical references:

• Babinski, J. (1918). Anosognosie. Rev Neurol (Paris). 31: 365-7.

• Baños, R. and Perpiña, C. (2002). Exploración Psicopatológica. Madrid: Síntesis.

• Belloch, A., Baños, R. and Perpiñá, C. (2008) Psychopathology of perception and imagination. In A. Belloch, B. Sandín and F. Ramos (Eds.) Manual de Psicopatología (2nd edition). Vol I. Madrid: McGraw Hill Interamericana

• Bembibre, J. and Arnedo, M. (2012). Neuropsicología de la corteza prefrontal dorsolateral I. En: M. Arnedo, J. Bembibre y M. Triviño (coord.), Neuropsicología: A Través de Casos Clínicos (pp. 177-188). Madrid: Editorial Médica Panamericana.

• Bisiach E, Vallar G, Perani D, Papagno C, Berti A (1986). Unawareness of disease following lesions of the right hemisphere: anosognosia for hemiplegia and anosognosia for hemianopia. Neuropsychologia. 1986;24(4):471-82.

• Orfei, M. D., y cols. (2007). Anosognosia for hemiplegia after stroke is a multifaceted phenomenon: A systematic review of the literature. Brain, 130, 3075-3090.

• Ownsworth, T., y Clare, L. (2006). The association between awareness deficits and rehabilitation outcome following acquired brain injury. Clinical Psychology Review, 26, 783–795.

• Prigatano, G. P. (2009). Anosognosia: Clinical and ethical considerations. Current Opinion in Neurology, 22, 606-611.

• Prigatano, G. (2010). The study of anosognosia. Oxford University Press.

• Schachter, D.L. (1992). Consciousness and awareness in memory and amnesia: critical issues. En The Neuropsychology of Consciousness. Milner y Rugg. Academic Press London

• Tremont, G. & Alosco, M.L. (2010). Relationship between cognition and awareness of deficit in mild cognitive impairment. Int J Geriatr Psychiatry.