Lingual gyrus

The lingual gyrus, also known as the medial occipitotemporal gyrus, is a brain structure that is linked to processing vision, especially related to letters. It is thought to also play a role in analysis of logical conditions (i.e., logical order of events) and encoding visual memories. It is named after its shape, which is somewhat similar to a tongue. Contrary to the name, the region has little to do with speech. It is believed that a hypermetabolism of the lingual gyrus is associated with visual snow. (Wikipedia)