ABSTRACT
Implicit learning is learning of complex information, without the use of conscious hypothesis testing strategies, and without resultant consciously accessible knowledge sufficient to account for performance on an indirect test of learning (Seger, 1994). Most research in implicit learning has used tasks in which subjects learn relationships between stimulus elements. For example, in artificial grammar learning, subjects learn letter bigrams and trigrams and rules relating letters to each other (Seger, 1994; Knowlton & Squire 1996). Relatively little work has investigated subjects' ability to implicidy learn about invariant properties of complex stimuli (Frick & Lee, 1995). Learning relationships between items may require different forms of processing than identifying such invariants.
