In search of meaning: reading and writing in Alzheimer's disease.

Decline in semantic memory is a key feature of Alzheimer's disease, and reading and writing performance reflects this loss. The article presents an overview of theoretical reading and spelling models, including definitions of key terminology and controversies surrounding the interaction of semantics and the orthographic lexicon. We review literature supporting a direct lexical nonsemantic route in reading and writing. The reading and writing deficits of Alzheimer's disease are contrasted with those of semantic dementia. Methods of assessing semantic memory in reading and writing are outlined, including administering published tests, word lists, homophones, written confrontation naming, verbal fluency, and written narrative analysis.