How do brains build two maps at once?

Neuroscientists modeled how two types of spatial cells in the brain could emerge together during development. A recurrent network trained only to predict sensory observations spontaneously developed both grid cells (which form hexagonal firing patterns) and place cells (which fire at specific locations), matching the reciprocal connections between entorhinal cortex and hippocampus. The model reproduces real phenomena like grid reorganization in mazes and the developmental sequence where place cells mature before grid cells, suggesting navigation might self-organize from a single objective: predicting what you'll see next.