Embracing complexity: using the attribute model to elucidate the role for distributed neural networks underlying spatial memory processes

Introduction Rodent models of spatial process­ ing have long been used as a model for human memory deficits, par­ ticularly as related to hippocampal function. What has been long absent in these analyses, however, is a thor­ ough description and rigorous study of the distributed neural networks asso ciated with spatial processing— both in the human and rodent. There is a trend emerging in research to expand beyond the hippocampus for evaluating spatial memory, but the thrust of the research still focuses on the role of the hippocampus as essential and other neural substra­ tes as performing subservient roles to the hippocampal processing. This review will describe spatial memory in terms of an attribute specificity model and demonstrate the nature of spatial processing in the rodent brain as well as describe a testable theoret­ ical model concerning the fundamen­ tal mechanisms whereby rodents perform spatial memory tasks. In particular, a pivotal role for the ret­ rosplenial cortex in spatial memory processing is outlined in the context of interacting memory systems. Conclusion Based on the proposed role for the retrosplenial cortex as an inter­ face between the event­based and knowledge­based memory systems, it seems logical that evaluating spa­ tial processing using tests of event­ based, knowledge­based and tests of the event­based and knowledge­ based memory systems’ interactions would serve to tease apart the role for the retrosplenial cortex more pre­ cisely than previously possible.