Short communicationThe retrosplenial cortex is necessary for path integration in the dark

- Rats with retrosplenial cortex lesions were trained in a path integration task with minimal memory requirements, in light and darkness.
- Lesioned and sham groups used a path integration strategy in both lighting conditions.
- Lesioned rats showed path integration impairment in darkness but not in light.
- The retrosplenial cortex is important for path integration and incorporates visuospatial information, irrespective of task-related spatial memory, to maintain path integration accuracy.

An increasing amount of data indicates that the retrosplenial cortex (RSC) plays a role in navigation and spatial memory. Moreover, it has been suggested that the RSC integrates mnemonic spatial features of the environment with self-motion information therefore enabling accurate path integration in darkness. This hypothesis rests on data obtained from animals trained in spatial memory tasks involving the conjoint use of allothetic and idiothetic information [8]. We examined the contribution of the RSC when animals are submitted to a path integration task with minimal memory requirement in light and dark. We found that RSC-lesioned rats exhibited a path integration deficit in the dark but not in the light. This suggests that the RSC is important for path integration and incorporates visuospatial information to maintain path integration accuracy.