This strange syndrome appears in people who believe they see despite having cortical blindness.
Of all the senses oriented to the perception of the outside world, that of vision is the one that is most developed in the human being.
Our visual ability allows us to detect and process highly detailed information from the world around us, giving us the ability to perceive a large amount of information regarding the stimuli that surround us. 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 lose visual capacity to a great extent or even totally.
In those people who were born with the ability to see but who abruptly lose it after a brain injury, sometimes a strange condition arises in which despite not being able to visually perceive the environment, they are convinced that they do. It’s about Anton’s syndrome, which we are going to talk about throughout this article.
Anton syndrome: main features
It is called Anton syndrome, a medical condition characterized by the presence of anosognosia or lack of awareness of the presence of alterations that occurs in people who have completely lost vision at an objective level after having suffered a brain injury that destroys the areas cortices in charge of 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 the non-vision.
The person who suffers from this condition is not hiding or pretending, but is actually unable to detect that he cannot see and acts as if he had the ability to perceive the environment through his eyes. In this situation, the subject visually conspires, that is to say, she mentally and unconsciously generates the content she would see, sometimes using information from her other senses, which sometimes may seem to have a certain precision. Even if they usually stumble often due to their lack of vision, the denial of blindness is usually continuous and persistent, although in confrontation with visual stimuli they often give imprecise answers.
Although their visual organs are functional, the visual cortex, which allows the processing and perception of visual information, is destroyed or disconnected, making vision not possible (a condition known as cortical blindness). Anton’s syndrome is usually accompanied by some compromise of cognitive functions, which 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 of this, they often have trips and sometimes even accidents that can endanger their physical integrity.
Furthermore, the mixture of blindness and denial of it 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 actually being able to do so) or work (in which their performance it will be obviously reduced and in which depending on the type of employment they may even commit negligence due to their problems).
As a general rule, the causes of the appearance of Anton’s syndrome are in the presence of a brain injury. 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 cerebral hemispheres. This injury is the origin of the 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 has also generated damage or alterations in the occipitotemporal regions that would serve as an area of association.
The causes of the lesion can be multiple, the most common being the presence of cerebrovascular accidents (either 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 vascular problems that may affect this.
Anton’s syndrome is an alteration whose treatment is complex, and generally requires the 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 is generally chronic, although in some cases there may be some improvement if capacities such as light capture are preserved and / or if the cause of blindness is partially reversible (it is very rare but sometimes the resorption of a hemorrhage or the treatment of some infections that cause blindness could imply some improvement).
At a medical level, an attempt will be made to treat the cause and the 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 this.
Regardless of this, the treatment will require an intervention at the level of awareness of the subject of their current situation and the existence of visual problems. In this sense, it may be necessary to restructure their beliefs by proposing behavioral experiments. This is a first step that can be essential for the patient to adhere to rehabilitation and neurological or functional stimulation programs, so that the patient can learn mechanisms to reduce the difficulties that their condition generates.
Psychoeducation is essential, especially for the affected person but also for their immediate environment, which is also usually the reason that the patient comes to consultation and is usually more concerned than the subject himself (who after all believes that he sees perfectly ).
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