Q: What is Alexia?
Answer: Alexia is the inability to recognize or comprehend written language. In other words, "Alexia" refers to a loss of already developed reading ability.
Alexia typically occurs after a stroke or damage to the dominant hemisphere of the brain. Usually, it occurs with other symptoms of stroke but pure alexia can occur too, where an individual's ability to produce written language is spared even though they are unable to understand written text.
Petersen, A., Vangkilde, S., Fabricius, C., Iversen, H., Delfi, T., & Starrfelt, R. (2015). "Visual Attention in Posterior Stroke and Relations to Alexia". Neuropsychologia. 58: 1521