Japanese scientists just built human brain circuits in the lab

Researchers in Japan built a miniature human brain circuit using fused stem-cell–derived organoids, allowing them to watch the thalamus and cortex interact in real time. They found that the thalamus plays a decisive role in maturing the cortex and organizing its neural networks. Signals from the thalamus triggered synchronized activity in specific neuron types, while others remained unaffected. The system closely mimics human brain development and could transform how scientists study neurological disorders.