A classic experiment by Hyde and Jenkins (1973) illustrates this. These researchers gave participants lists of words, which they later tested recall of, as their memory items. To affect their thinking about the words, half the participants were told to rate the pleasentness of each word, and half were told to check if the word contained the letters ‘e’ or ‘g’. This manipulation was designed to affect ‘depth of processing’. The participants in the rating-pleasentness condition had to think about what the word meant, and relate it to themselves (how they felt about it) – “deep processing”. Participants in the letter-checking condition just had to look at the shape of the letters, they didn’t even have to read the word if they didn’t want to – “shallow processing”. The second, independent, manipulation concerned whether participants knew that they would be tested later on the words. Half of each group were told this – the “intentional learning” condition – and half weren’t told, the test would come as a surprise – the “incidental learning” condition.
This is a lousy design: the letter looking design sounds more like distraction than a formal treatment. Intention does matter in learning.