Anton syndrome: symptoms, causes and treatment

Among all the senses oriented to the perception of the external world, vision is the most developed in humans.

Our visual capacity allows us to detect and process highly detailed information about the world around us. surrounds us, giving us the ability to perceive a large amount of information regarding the stimuli that surround. However, sight is a sense that can be lost or not possessed: there are a large number of alterations that can cause a person to be born without the ability to see or to lose much or even all of the ability visual.

In those people who were born with the ability to see but lose it abruptly after a brain injury, sometimes a strange condition in which, despite not being able to perceive the environment at a visual level, they are convinced that they do do. This is Anton's syndrome., about which we are going to talk throughout this article.

• Related article: "Occipital lobe: anatomy, characteristics and functions"

Anton syndrome: main features

Anton's syndrome is a medical condition characterized by the presence of anosognosia or

Lack of awareness of the presence of alterations that occurs in people who, at an objective level, have completely lost their vision after having suffered a brain injury that destroys the cortical areas responsible for processing this type of information.

It is a type of visual agnosia, that is, a lack of recognition of the visual information that the subject receives, although in this case it is due to non-recognition of non-vision.

Symptoms

The person who suffers from this condition is not disguising or pretending, but really he is unable to detect that he cannot see and acts as if he possessed the ability to perceive the environment through his eyes. In this situation, the subject conspires visually, that is, he mentally and unconsciously generates the content that he would see, sometimes using information from their other senses with what can sometimes seem to have some precision. Even if they often stumble due to their lack of vision, denial of blindness is often continuous and persistent, although in confrontation with visual stimuli they usually give little responses accurate.

Although your visual organs are functional, the visual cortex, which enables the processing and perception of visual information, is destroyed or disconnected, so that vision is not possible (a condition known as blindness cortical). Anton's syndrome usually usually accompanied by some compromise of cognitive functions, that occur comorbidly but are not part of the syndrome itself, such as memory problems.

Since they are not able to perceive that they do not see and because they move normally as a result, they often have frequent setbacks and sometimes even accidents that can endanger their integrity physical.

Besides it the mixture of blindness and denial of this implies that dysfunctionalities arise in spheres such as social, academic (it is not uncommon for them to claim to be able to read and write despite not really being able to do so) or work (in which generally their performance will obviously be reduced and in which, depending on the type of employment, they may even commit negligence due to their problematic).

• You may be interested in: "Cortical blindness: causes, symptoms and treatment"

Causes

As a general rule, the causes of the appearance of Anton's syndrome are found in the presence of a brain lesion. Said lesion must produce an affectation, destruction or disconnection of the visual areas of the occipital lobe at a bilateral level, that is, affecting the occipital region of both brain hemispheres. This lesion is the origin of cortical blindness that prevents them from seeing.

The reason for the appearance of anosognosia is not so clear, although it is common to find that the injury suffered it has also generated damage or alterations in the occipitotemporal regions that would serve as the association area.

The causes of the appearance of the lesion can be multiple, the most common being the presence of cerebrovascular accidents (whether due to ischemia or hemorrhage).

In addition to this, other possible causes of its appearance are head injuries, the presence of infections or compression caused by brain tumors. High blood pressure, smoking or diabetes are risk factors for the emergence of vascular problems that can affect this.

Treatment

Anton's syndrome is a disorder whose treatment is complex, and generally requires joint work of a multidisciplinary team that takes into account the different needs and particularities of the case in question.

To begin with, it is necessary to understand that cortical blindness It is generally chronic, although in some cases there may be some improvement if abilities such as light capture are preserved and/or if the cause of blindness is partially reversible (it is very rare but sometimes the reabsorption of a hemorrhage or the treatment of some infections that cause blindness could imply some improvement).

At the medical level, efforts will be made to treat the cause and brain injury in the best possible way, something that may or may not include surgery. However, this would be to treat the cause itself and not so much Anton's syndrome, which can be understood as a complication of it.

Regardless of this, the treatment will require an intervention at the level of awareness of the subject of his current situation and the existence of visual problems. In this sense it may be necessary restructure their beliefs by proposing behavioral experiments. This is a first step that can be essential for the patient to adhere to rehabilitation and stimulation programs neurological or functional, so that the patient can learn mechanisms to reduce the difficulties that his condition generate.

Psychoeducation is paramount, especially for the person affected but also for those close to him, which is also usually the reason why the patient comes to the consultation and is usually more concerned than the subject himself (who, after all, believes that he sees perfectly).

Bibliographic references:

• Belloch, A., Baños, R. and Perpigná, C. (2008) Psychopathology of perception and imagination. in a. Belloch, B. Sandin and F. Ramos (Eds.) Manual of Psychopathology (2nd edition). Vol I Madrid: McGraw Hill Interamericana.
• Donoso, A. (2002). Anosognosia in brain diseases. Rev.chil.neuro-psychiatr., 40 (2).
• Kaufmann, D. (2008). Clinical neurology for psychiatrists. Sixth edition. Elsevier.
• Misra, M.; Rath, S. & Mohanty, A.B. (1989). Anton syndrome and cortical blindness due to bilateral occipital infarction. Indian Journal of Ophthalmology, 37 (4): 196.
• Prigatano, G. (2010). The study of anosognosia. Oxford University Press.