TY - JOUR TI - Replay as wavefronts and theta sequences as bump oscillations in a grid cell attractor network AU - Kang, Louis AU - DeWeese, Michael R A2 - Deshmukh, Sachin A2 - Colgin, Laura L A2 - Deshmukh, Sachin A2 - Blair, Tad VL - 8 PY - 2019 DA - 2019/11/18 SP - e46351 C1 - eLife 2019;8:e46351 DO - 10.7554/eLife.46351 UR - https://doi.org/10.7554/eLife.46351 AB - Grid cells fire in sequences that represent rapid trajectories in space. During locomotion, theta sequences encode sweeps in position starting slightly behind the animal and ending ahead of it. During quiescence and slow wave sleep, bouts of synchronized activity represent long trajectories called replays, which are well-established in place cells and have been recently reported in grid cells. Theta sequences and replay are hypothesized to facilitate many cognitive functions, but their underlying mechanisms are unknown. One mechanism proposed for grid cell formation is the continuous attractor network. We demonstrate that this established architecture naturally produces theta sequences and replay as distinct consequences of modulating external input. Driving inhibitory interneurons at the theta frequency causes attractor bumps to oscillate in speed and size, which gives rise to theta sequences and phase precession, respectively. Decreasing input drive to all neurons produces traveling wavefronts of activity that are decoded as replays. KW - grid cell KW - replay KW - phase precession KW - theta sequence KW - continuous attractor KW - wavefront JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -