Anton syndrome: symptoms, causes and treatment

Of all the senses oriented towards the perception of the outside world, that of vision is the most developed in human beings.

Our visual ability allows us to detect and process very detailed information about the world around us, giving us the ability to perceive a large amount of information regarding the stimuli around us. However, sight is a sense that may or may not be lost: there are many impairments that can cause a person to be born without the ability to see or to lose a lot or even completely the ability to see.

In those people who are born with the ability to see but lose it suddenly after brain injury, sometimes a strange situation occurs in which, although not able to visually perceive the environment, they are convinced that they do. It’s Anton syndrome, Which we will talk about throughout this article.

    Anton syndrome: main features

    It is called Anton’s syndrome a medical condition characterized by the presence of anosognosia or lack of awareness of the presence of alterations occurring in people who, on an objective level, have completely lost their sight 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 is due to the non-recognition of the non-vision.


    The person suffering from this condition does not hide or pretend, but he is unable to detect that he cannot see and acts as if you have the ability to perceive the environment through your eyes. In this situation the subject conspires visually, that is to say mentally and unconsciously generates the content that he would see, sometimes using for this information from his other senses with which sometimes it may seem that they have a certain precision. Although they often stumble due to their lack of vision, blindness denial is usually continuous and persistent, although when faced with visual stimuli, they often give inaccurate answers.

    While its 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 cortical blindness). Anton syndrome in general usually accompanied by some compromise in cognitive functions, Which occur concomitantly but are not part of the syndrome itself, such as memory problems.

    Because they are unable to perceive that they cannot see and because they move normally as a result, they often have trips and sometimes even accidents which can jeopardize their physical integrity.

    Furthermore the mixture of blindness and denial implies that dysfunction occurs in areas such as social, academic (it is not uncommon for them to claim to know how to read and write when they are not able to do so effectively) or employment (in which their performance will generally obviously be reduced and in which according to the type employment may even be negligent due to their problems).

      the causes

      As a rule, the causes of the appearance of Anton’s syndrome are found in the presence of a brain injury. This lesion must lead to destruction or bilateral disconnection of the visual areas of the occipital lobe, that is to say affecting the occipital region of both cerebral hemispheres. This lesion is the cause of cortical blindness which prevents them from seeing.

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

      The causes of the injury can be many, the most common being the presence of stroke (Whether for ischemia or hemorrhage).

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


      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 it is usually chronic, although in some cases there may be some improvement if abilities such as light capture are retained and / or if the cause of blindness is partially reversible (this is very rare but sometimes reabsorption of bleeding or treatment of certain infections causing blindness may result in some improvement).

      At the medical level, efforts will be made to best treat the cause and the head trauma, which may or may not include surgery. However, this would be treating the cause itself and not so much Anton’s syndrome, which can be understood as a complication of it.

      Either way, treatment will require intervention in the subject’s awareness of their current situation and the existence of visual problems. In this regard, it may be necessary restructure their beliefs by offering behavioral experiences. This is a first step that can be crucial for the patient to join rehabilitation programs and neurological or functional stimulation, so that the patient can learn mechanisms to reduce the difficulties that their condition generates.

      Psychoeducation is essential, Especially for those affected but also for their immediate environment, which is also generally the reason why the patient goes for consultation and is generally more concerned than the subject himself (who in the end thinks he can see perfectly).

      Bibliographical references:

      • Belloch, A., Bains, R. and Perpiñá, C. (2008) Psychopathology of perception and imagination. In A. Belloch, B. Sandín and F. Ramos (Eds.) Handbook of Psychopathology (2nd edition). Vol I, Madrid: McGraw Hill Interamericana.
      • Donoso, A. (2002). Anosognosia in diseases of the brain. Rev.chil.neuro-Psychiatry., 40 (2).
      • Kaufman, D. (2008). Clinical neurology for psychiatrists. Sixth edition. Elsevier.
      • Misra, M .; Rath, S. and Mohanty, AB (1989). Anton syndrome and cortical blindness due to bilateral occipital infarction. Indian Journal of Ophthalmology, 37 (4): 196.
      • Prigatano, G. (2010). Research of anosognosis. Oxford University Press.

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