This review mainly focuses on language disorders. One type of language disorder is known as aphasia. Aphasia is generally occurring due to secondary lesions that appear on subcortical white matter that injures the left hemisphere and hence causes dysfunction in linguistic information such as grammar, syntax, morphology, semantics and other aspects of language. Aphasia is considered an acquired language disorder as it blocks the language usage as a whole. Aphasia can be of primary and secondary. Primary aphasia deals with problems associated with language mechanisms whereas secondary aphasia deals with problems associated from memory, attention and perceptual impairment.

Primary progressive aphasia also abbreviated as PPA, is a neurodegenerative disorder that is closely associated with any form of cerebrovascular accident such as stroke, cerebral tumours and brain injury that affects the middle cerebral artery and its branches. Primary progressive aphasia also tends to form when there is family history and 2-3 siblings receive it. It is led to believe that people inherit PPA due to the mutation of a particular gene known as progranulin on chromosome 17q21.31. While progranulin gene is mutated, a hyperphosphorylated protein is deposited in brain known as tau in the form of intraneuronal neurofibrillary tangles or otherwise known as pick bodies.