  Neurodegeneration characterizes individuals with different dementia subtypes
(e.g., individuals with Alzheimer's Disease, Primary Progressive Aphasia, and
Parkinson's Disease), leading to progressive decline in cognitive, linguistic,
and social functioning. Speech and language impairments are early symptoms in
individuals with focal forms of neurodegenerative conditions, coupled with
deficits in cognitive, social, and behavioral domains. This paper reviews the
findings on language and communication deficits and identifies the effects of
dementia on the production and perception of discourse. It discusses findings
concerning (i) language function, cognitive representation, and impairment,
(ii) communicative competence, emotions, empathy, and theory-of-mind, and (iii)
speech-in-interaction. It argues that clinical discourse analysis can provide a
comprehensive assessment of language and communication skills in individuals,
which complements the existing neurolinguistic evaluation for (differential)
diagnosis, prognosis, and treatment efficacy evaluation.
