How experience shapes hippocampal place cell activity to create flexible cognitive maps

The mammalian brain is known to produce mental representations of the spatial environment, known as cognitive maps, that help humans and animals navigate their surroundings. A subpopulation of neurons in the CA1 area of the hippocampus, which are referred to as place cells (PCs), have been found to become active when animals visit specific places or locations in their environment.

The activation of these cells was previously linked to the encoding of space- and goal-related information, which was predicted to support the creation of cognitive maps. While numerous past studies explored the function of PCs and their contribution to the creation of cognitive maps, the role of experience in shaping the creation of these maps has not yet been elucidated.

Researchers at Baylor College of Medicine recently shed new light on the mechanisms through which experience could influence the encoding of information by PCs. Their findings, published in Nature Neuroscience, suggest that experiences produce an adjustment of synaptic input in the mouse brain, which in turn affects the activity of PCs, enabling the production of flexible cognitive maps.

“Hippocampal CA1 PCs encode both space- and goal-referenced information to support a cognitive map,” wrote Fish Kunxun Qian, Yiding Li and Jeffrey C. Magee in their paper. “The mechanism of this referencing and the role of experience remain poorly understood. Here we longitudinally recorded PC activity while head-fixed mice performed a spatial learning task on a treadmill.”

Essentially, Qian, Li and Magee recorded the activity of PCs in the hippocampus, specifically in the CA1 area, within the brain of 22 adult mice as they performed a spatial learning task. The recordings were collected using two techniques: two-photon imaging and in vivo intracellular recording via an implanted electrode.

“In a familiar environment, the CA1 representation consisted of PCs that were referenced to either specific spatial locations or a reward goal in approximately equal proportions,” wrote Qian, Li and Magee. “However, the CA1 representation became predominately goal-referenced upon exposure to a novel environment, as space-referenced PCs adaptively switched reference frames.”

The recordings collected by this team of researchers suggest that when mice start navigating a new environment, the representations produced by place cells in the CA1 region of their hippocampus become increasingly goal-oriented. This suggests that the animals’ experience influences the creation of cognitive maps, which ensure that these maps best assist them in completing spatial tasks and achieving their goals.

“Intracellular membrane potential recordings revealed that individual CA1 neurons simultaneously received both space- and goal-referenced synaptic inputs, and the ratio of these inputs was correlated with individual PC referencing,” wrote Qian, Li and Magee. “Furthermore, behavioral timescale synaptic plasticity shaped PC referencing. Together, these results suggest that experience-dependent adjustment of synaptic input shapes PC referencing to support a flexible cognitive map.”

Overall, the recent findings gathered by Qian, Li and Magee suggest that in mice, the adjustment of cognitive maps based on experience can at least partly be explained by the dynamic reorganization of synaptic inputs. Future studies could further test this hypothesis and validate the team’s findings, improving the present understanding of the neural processes supporting experience-based spatial learning and navigation.

© 2025 Science X Network

The mammalian brain is known to produce mental representations of the spatial environment, known as cognitive maps, that help humans and animals navigate their surroundings. A subpopulation of neurons in the CA1 area of the hippocampus, which are referred to as place cells (PCs), have been found to become active when animals visit specific places or locations in their environment.

The activation of these cells was previously linked to the encoding of space- and goal-related information, which was predicted to support the creation of cognitive maps. While numerous past studies explored the function of PCs and their contribution to the creation of cognitive maps, the role of experience in shaping the creation of these maps has not yet been elucidated.

Researchers at Baylor College of Medicine recently shed new light on the mechanisms through which experience could influence the encoding of information by PCs. Their findings, published in Nature Neuroscience, suggest that experiences produce an adjustment of synaptic input in the mouse brain, which in turn affects the activity of PCs, enabling the production of flexible cognitive maps.

“Hippocampal CA1 PCs encode both space- and goal-referenced information to support a cognitive map,” wrote Fish Kunxun Qian, Yiding Li and Jeffrey C. Magee in their paper. “The mechanism of this referencing and the role of experience remain poorly understood. Here we longitudinally recorded PC activity while head-fixed mice performed a spatial learning task on a treadmill.”

Essentially, Qian, Li and Magee recorded the activity of PCs in the hippocampus, specifically in the CA1 area, within the brain of 22 adult mice as they performed a spatial learning task. The recordings were collected using two techniques: two-photon imaging and in vivo intracellular recording via an implanted electrode.

“In a familiar environment, the CA1 representation consisted of PCs that were referenced to either specific spatial locations or a reward goal in approximately equal proportions,” wrote Qian, Li and Magee. “However, the CA1 representation became predominately goal-referenced upon exposure to a novel environment, as space-referenced PCs adaptively switched reference frames.”

The recordings collected by this team of researchers suggest that when mice start navigating a new environment, the representations produced by place cells in the CA1 region of their hippocampus become increasingly goal-oriented. This suggests that the animals’ experience influences the creation of cognitive maps, which ensure that these maps best assist them in completing spatial tasks and achieving their goals.

“Intracellular membrane potential recordings revealed that individual CA1 neurons simultaneously received both space- and goal-referenced synaptic inputs, and the ratio of these inputs was correlated with individual PC referencing,” wrote Qian, Li and Magee. “Furthermore, behavioral timescale synaptic plasticity shaped PC referencing. Together, these results suggest that experience-dependent adjustment of synaptic input shapes PC referencing to support a flexible cognitive map.”

Overall, the recent findings gathered by Qian, Li and Magee suggest that in mice, the adjustment of cognitive maps based on experience can at least partly be explained by the dynamic reorganization of synaptic inputs. Future studies could further test this hypothesis and validate the team’s findings, improving the present understanding of the neural processes supporting experience-based spatial learning and navigation.

© 2025 Science X Network