Learning has been defined functionally as changes in behavior that result fromexperience or mechanistically as changes in the organism that result from experience. Bothtypes of definitions are problematic. We define learning as ontogenetic adaptation, that is, aschanges in the behavior of an organism that result from regularities in the environment of theorganism. This functional definition not only solves the problems of other definitions but alsohas important advantages for cognitive learning research. 

What is learning? On the nature and merits of a functional definition of learning