The left temporal lobe is primarily the brain's speech and language recognition center, controlling a person's ability to speak, write, and understand verbal and written language. It does not govern the ability to see and hear, but rather the ability to comprehend the meaning of words.
There is also some evidence to suggest that the semantics recognized by the left temporal lobe also extend to numbers and mathematical symbols. In addition to having difficulty recognizing familiar words and names, some people with left temporal lobe damage also have problems with math problems and gain a tendency to transpose numbers written in a sequence.
