Implicit learning refers to situations in which a person learns about the structure of a stimulus environment without necessarily intending to do so. It is different from explicit learning which is defined as the conscious, intentional, and commonly hypothesis- guided acquisition of knowledge. The primary goal of this proposal is to investigate age-related differences in implicit and explicit learning on the process control task, and to determine how trying to learn influences learning when either complex or simple regularities are used. [Only one study of aging with the process control task has been reported, but it focused only on young versus middle aged people.] A secondary goal is to use aging to test theories, which assume that salient (simple) patterns engage an explicit system whereas non-salient (more complex) patterns engage an implicit system. So, the specific aims are to identify age-related differences in implicit and explicit learning on the process control task (Aim 1), and the effects of trying to discover a pattern on implicit and explicit learning (Aims 2 and 3). To achieve these goals, three experiments are proposed in which younger and older adults perform a task based on the work of Berry and Broadbent (1988) in which they attempt to control the production of a hypothetical sugar factory by varying the number of workers employed. These experiments have a practical relevance in that findings obtained here could be helpful in optimizing educational and rehabilitation procedures.