Configural and elemental processing in associative learning: commentary on Melchers, Shanks and Lachnit.

The paper by Melchers, Shanks, and Lachnit (2007) reviews the available evidence suggesting that there is flexible processing, such that some associative learning tasks can be solved either configurally or elementally. We find the evidence provocative but limited in its demonstrated generality and silent with respect to the theoretical mechanisms that might regulate the alleged flexibility of processing. Further research is invited to determine the scope of the variation involved and how best to account for it. At present, theories, either elemental or configural, that include mechanisms to shift the weight assigned to component stimuli appear to be potential candidates for embracing the data.