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Adaptive modulation of theta sweeps in the brain’s navigation circuit

| Source: Science

Efficient navigation requires prioritizing information from behaviorally relevant locations. In rats, such selective sampling may arise from theta-paced sweeps in grid and place cell populations, which scan nearby space in a left-right alternating pattern coordinated by parasubicular direction signals. This alternation promotes uniform spatial coverage during exploration, but whether sweeps can be flexibly tuned to moment-to-moment demands remains unknown. Using large-scale Neuropixels recording

Efficient navigation requires prioritizing information from behaviorally relevant locations. In rats, such selective sampling may arise from theta-paced sweeps in grid and place cell populations, which scan nearby space in a left-right alternating pattern coordinated by parasubicular direction signals. This alternation promotes uniform spatial coverage during exploration, but whether sweeps can be flexibly tuned to moment-to-moment demands remains unknown. Using large-scale Neuropixels recordings in freely behaving rats, we show that sweeps and direction signals are rapidly and dynamically modulated: They track moving targets during pursuit, precede orienting responses during immobility, and reverse during backward locomotion—all without prior spatial learning of goal locations. Comparable modulation occurs during rapid eye movement (REM) sleep. Together, these findings identify sweeps as a flexible, attention-like mechanism for selectively sampling allocentric cognitive maps.

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