Chongxi Lai et al., Volitional activation of remote place representations with a hippocampal brain–machine interface. Science382,566-573(2023).DOI:10.1126/science.adh5206

Editor’s summary

“The hippocampus holds a model of the environment that can be mentally traversed during recall or simulation. It is unknown whether animals can intentionally control their hippocampal activity according to their model of the world. By combining virtual reality and a real-time brain‐machine interface, Lai et al. discovered that rats directly controlled their hippocampal neuronal firing in a goal-directed manner (see the Perspective by Coulter and Kemere). Rats first formed a hippocampal map of a virtual environment. Then, in brain‐machine interface mode, they demonstrated the ability to activate representations from this map corresponding to specific remote locations, which then brought either them or an object to spatial goals. The rats could sustain a hippocampal representation of a remote location for tens of seconds, reminiscent of human imagination or mental time travel. —Peter Stern”

Abstract

“The hippocampus is critical for recollecting and imagining experiences. This is believed to involve voluntarily drawing from hippocampal memory representations of people, events, and places, including maplike representations of familiar environments. However, whether representations in such “cognitive maps” can be volitionally accessed is unknown. We developed a brain–machine interface to test whether rats can do so by controlling their hippocampal activity in a flexible, goal-directed, and model-based manner. We found that rats can efficiently navigate or direct objects to arbitrary goal locations within a virtual reality arena solely by activating and sustaining appropriate hippocampal representations of remote places. This provides insight into the mechanisms underlying episodic memory recall, mental simulation and planning, and imagination and opens up possibilities for high-level neural prosthetics that use hippocampal representations.”

Chongxi Lai et al., Volitional activation of remote place representations with a hippocampal brain–machine interface. Science382,566-573(2023).DOI:10.1126/science.adh5206

Michael E. Coulter, Caleb Kemere ,The neural basis of mental navigation in rats. Science 382,517-518(2023).DOI:10.1126/science.adl0806