Alexia is a neurological disorder characterized by an acquired loss of the ability to comprehend written language, despite the preservation of intact vision. It is a rare neurological condition that is caused by damage to the language-processing areas of the brain (Karnath, 2004). The disorder is also known as pure alexia, visual alexia, and word blindness.
The condition can be acquired due to a stroke or traumatic brain injury (TBI), or it can be caused by a progressive neurological disorder such as multiple sclerosis (MS) or a tumor (Karnath & Riddoch, 2004). In some cases, alexia can be caused by a congenital problem, such as an abnormal development of certain brain structures (Karnath et al., 2005). In any case, the cause of alexia is usually a result of damage to an area of the brain known as the left occipitotemporal region, which is responsible for the interpretation of written language (Karnath & Riddoch, 2004).
The primary symptom of alexia is the inability to read and comprehend written language. This is even though the person may have normal vision and can recognize letters, words, and symbols. People with alexia may also experience difficulty with writing, spelling, and writing in the same language they can comprehend (Karnath et al., 2005).
The diagnosis of alexia is based on a medical history, physical examination, and a neurological examination. Other tests, such as imaging studies, may be used to help diagnose the condition. Treatment of alexia typically involves rehabilitation therapy to help the person relearn how to read, write, and comprehend language. In some cases, medications may also be used to help improve language-processing abilities (Karnath et al., 2005).
In conclusion, alexia is a neurological disorder characterized by an acquired loss of the ability to comprehend written language, despite the preservation of intact vision. The condition is usually caused by damage to the left occipitotemporal region of the brain, and the primary symptom is difficulty reading and comprehending language. The diagnosis and treatment of alexia typically involve a combination of rehabilitation therapy and medications, depending on the cause.
Karnath, H. O. (2004). Impairments of visual object recognition and their functional-anatomical correlates. Current Opinion in Neurology, 17(2), 229-236.
Karnath, H. O., & Riddoch, M. J. (2004). The neuropsychology of visual object recognition. Neuropsychologia, 42(2), 239-252.
Karnath, H. O., Küker, W., & Himmelbach, M. (2005). Alexia: A clinical-anatomical review. Brain, 128(4), 683-699.