AI Insight
This study investigates how visual information reaches the hippocampus to shape spatial maps in mice. Researchers found that hippocampal neurons form distinct spatial representations depending on whether mice navigate in light or darkness, and that this difference persists even after removal of the primary visual cortex. Critically, blocking the superior colliculus-to-lateral visual cortex pathway — an evolutionarily ancient midbrain route — significantly reduced the difference between light and dark maps, identifying this pathway as a key conduit for visual signals informing hippocampal spatial coding.
Why it matters
These findings may help explain why some cortically blind humans retain residual visual navigation abilities, suggesting that therapeutic strategies targeting subcortical visual pathways could potentially support spatial orientation in patients with damage to the visual cortex.
⚠️ Preprint – Noch nicht peer-reviewed
Dieser Artikel wurde noch nicht von unabhängigen Experten begutachtet. Die Ergebnisse sind vorläufig und sollten mit Vorsicht interpretiert werden.
Mammals rely on their senses to establish their position in space. Neural activity in the hippocampus maps position, yet how sensory signals reach the hippocampus remains poorly understood. Here we uncover the visual pathways informing spatial maps in the mouse hippocampus. Hippocampal activity in mice traversing a track in alternating periods of light and darkness revealed two distinct maps, one in light and one in dark. Surprisingly, distinct maps persisted following bilateral ablations of primary visual cortex, indicating that visual signals still reach the hippocampus. Conversely, blocking the ancestral pathway linking superior colliculus to lateral visual cortex markedly reduced the difference between light and dark maps. Thus, this conserved pathway relays visual information to the hippocampus, potentially explaining residual visual navigation in cortically blind humans.
Source: Vision shapes neural maps of space through an ancient midbrain pathway