A new study reveals how interneurons, brain cells that regulate the firing of other neurons, act as traffic controllers in the hippocampus, a region critical for learning and memory. Researchers found that activating a single interneuron triggered synchronized brain cell activity during rest, potentially aiding memory formation. This discovery highlights how interneurons influence brain rhythms and suggests their dysfunction may contribute to disorders like epilepsy, autism, and schizophrenia. These findings could lead to targeted therapies for neurological conditions linked to abnormal brain rhythms.