Abstract: Four experiments were conducted to determine the magnitude of age-linked changes in the effects of long-term memory variables on verbal short-term memory performance, speeded speech processing, and error rates in young adults between 18-23 years and healthy older adults between 65-80 years. The goals of these experiments were twofold. First, the studies were an empirical investigation of whether a wide range of variables associated with language processing (lexical status, word length, word frequency, and phonological neighborhood density) and semantic processing (concreteness and semantic homogeneity of lists) affected the memory performance of young and older adults in different ways. Second, the studies were designed to enable tests of competing theories regarding the processes by which long-term memory variables affect verbal short-term memory processes more generally. Memory measures indicated small and frequently non-significant reductions in memory performance for the older adults relative to the young adults; results also indicated that all of the long-term memory variables tested made significant contributions to recall performance in both young and older adults. Despite a lack of significant age differences in the magnitude of their effects on memory measures, lexical status, word frequency and phonological neighborhood density all yielded significant interactions with age group in performance on speeded reading tasks used to measure rehearsal rate differences. Older adults made more speech errors relative to young adults for nonwords, low-frequency words, and words from sparse phonological neighborhoods, but not for other stimulus types. Results from these experiments are discussed in terms of the redintegration model, which accounts for long-term memory contributions to verbal short-term memory tasks in terms of a trace-recovery process within the phonological loop, and in terms of the binding model, an interactive language-memory framework that describes verbal short term memory tasks as a task of forming linkages between representations within the language system and an internal representation of context.