Myerson et al., (1990) suggest that experimental manipulations such as task complexity and/or practice may directly influence the rate of cognitive processing. A connection between an increase in age and an increase in cognitive processing time is well-established (see Salthouse, 1985 for a review). The effect of task complexity in magnifying this link has also been repeatedly demonstrated (see Cerella, Poon & Williams, 1980 for a review). Less is known, however, about the role of practice in minimizing age differences in cognitive processing, particularly when task complexity is manipulated (Spirduso & MacRae, 1990). Although it is expected that both young and old should benefit from practice, the implication is that the older population has more to gain because initially they are at a greater deficit. Therefore the purpose of this study was to investigate the relationship among age, task complexity and practice. Twenty subjects were divided into two age groups: 10 older (M age 57.2 years) and 10 younger (M age=24.5 years). Vocal reaction time was measured at two levels of cognitive complexity; low complexity (SVRT) and high complexity (CVRT). During SVRT the subjects uttered a target color (red, blue, or green) in response to a stimulus light. For CVRT, subjects had to determine the target color (red, blue or green) after they were given a directional cue and a stimulus light. All subjects practiced both versions of the task over four days. As anticipated, age-related differences, particularly for the complex task, were observed. The ANOVA results revealed both groups responded similarly on SVRT (younger M=.339 msec and older M=.388 msec) but the older group needed significantly more time (M=1.331 sec) than the younger group (M=1.050 sec) on CVRT. Also consistent with other findings was that practice led to significantly faster processing time for all subjects during both levels of task complexity (day one M=.848 msec and day four M=.713 msec). Practice led to significant improvement for both groups at both levels of task complexity. The older group however, did not experience a significantly disproportionate improvement in their CVRT time. Although practice may serve to reduce task novelty (Spirduso & MacRae, 1990) and/or improve processing efficiency (Salthouse & Somberg, 1982), additional practice (beyond four days) may be necessary to observe a significant reduction in the magnitude of age-related differences in cognitive processing time for complex tasks.Keyword(s): older adult/aging issues, performance