A cautionary note on interpreting the effects of partial reinforcement on place learning performance in the water maze

The effects of partial reinforcement on dry land and swimming pool place le arning tasks have recently been;compared and it has been suggested that the y differ fundamentally [8]. That is, partial reinforcement impairs performa nce in the water maze, but not on dry land. However, other evidence suggest s that partial reinforcement may have the opposite effect in the water maze , strengthening the accuracy and persistence of spatial responses. We discu ss how the discrepancy may depend on 'levels' of negative reinforcement (e. g. escaping to a submerged platform before complete removal from the pool) and how experimental procedures may set up competitive contingencies that r einforce alternative behaviors. Finally, we consider data from past lesion studies and suggest ways to improve the design of future water maze experim ents. (C) 2001 Published by Elsevier Science B.V. All rights reserved.