RT Journal Article
SR Electronic
T1 Long-term consolidation switches goal proximity coding from hippocampus to retrosplenial cortex
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 167882
DO 10.1101/167882
A1 E. Zita Patai
A1 Amir-Homayoun Javadi
A1 Jason D. Ozubko
A1 Andrew O’Callaghan
A1 Shuman Ji
A1 Jessica Robin
A1 Cheryl Grady
A1 Gordon Winocur
A1 Shayna R. Rosenbaum
A1 Morris Moscovitch
A1 Hugo J. Spiers
YR 2017
UL http://biorxiv.org/content/early/2017/07/25/167882.1.abstract
AB Recent research indicates the hippocampus may code the distance to the goal during navigation of newly learned environments. It is unclear however, whether this also pertains to highly familiar environments where extensive systems-level consolidation is thought to have transformed mnemonic representations. Here we recorded fMRI while University College London and Imperial College London students navigated virtual simulations of their own familiar campus (> 2 years of exposure) and the other campus learned days before scanning. Posterior hippocampal activity tracked the proximity to the goal in the newly learned campus, but not in the familiar campus. By contrast retrosplenial cortex tracked the distance to the goal in the familiar campus, but not in the recently learned campus. These responses were abolished when participants were guided to their goal by external cues. These results open new avenues of research on navigation and consolidation of spatial information and help advance models of how neural circuits support navigation in novel and highly familiar environments.Significance Statement Historically, research on the hippocampal formation has focused on its role in long-term memory and navigation – often in isolation. No study to date has directly compared realistic navigation within familiar with recently learned environments, nor has it been explored how the neural substrates, along with computational codes, may change. In this study, we show for the first time, a shift from hippocampal to cortical coding of distance to a goal during active navigation. This study bridges the gap between memory consolidation and navigation, and paves the way for more functional and realistic understanding of the hippocampus.