A study investigated language patterning, as an indication of synthetic mental activity, in comparison groups of normal pre-middle-aged adults (30-42 years), normal elderly adults (75-93), and elderly adults (71-91) with Alzheimer's dementia. Semiotic theory was used as the conceptual context. Linguistic measures included the Token Test, the Boston Diagnostic Aphasia Examination, and the Test for Syntactic Complexity. Results showed significant differences between pre-middle-aged and normal elderly in linguistic processing, indicating a direct relationship between language deficits and increased age. There also appears to be a definitive pattern in age-correlated deficits, showing non-random, predictable linguistic decrement. There is a direct relationship between language deficits and linguistic complexity within and across semiotic ranks, and an inverse relationship between language deterioration and language development. (MSE)