Left Fusiform Gyrus (occipital area)

Damage to certain areas involved with word and letter representations may cause pure alexia, or pure word blindness – individuals can understand spoken but not written language, otherwise vision is intact.

The fusiform gyrus has a posterior-anterior gradient for decoding increasingly complex visual orthographic representations (i.e. letter comprehension is posterior to visual word form area).

If visual word form area is damaged in mid-fusiform gyrus but posterior regions are spared, patients may suffer letter-by-letter dyslexia in which patients may perceive individual letters but not words (Fiset et al, 2005)

References

Fiset, D., Arguin, M., Bub, D., Humphreys, G. W. & Riddoch, M. J. How to Make the Word-Length Effect Disappear in Letter-by-Letter Dyslexia: Implications for an Account of the Disorder. Psychol. Sci. 16, 535–541 (2005) https://pubmed.ncbi.nlm.nih.gov/16008786/