Spatial event processing.

The present review advances experimental evidence on the cerebellar involvement in spatial data processing. In particular, data on Morris water maze (MWM) performances of hemicerebellectomized (HCbed) rats indicate a specific cerebellar role within the procedural aspects of spatial functions. In MWM testing, HCbed animals are impaired in developing efficient exploration strategies and display only old and rather ineffective ways for acquiring spatial information, such as peripheral circling around the pool. This behavior is not exhibited if spatial mapping abilities are preoperatively acquired. Thus, MWM experimental data point toward a procedural deficit that specifically impairs the acquisition phase. The characteristics of the cerebellar involvement in affecting the procedures needed for spatial data management are discussed in the light of recent theories on spatial data processing and on cerebellar timing and ordering functions.