Our brains are made up of networks of neurons where each individual nerve cell can make connections with thousands of others. AMPA receptors are a set of membrane proteins that mediate fast signal transmission across these connection points called synapses, with certain receptor complexes predominating in different parts of the brain. Ingo Greger’s group, in the LMB’s Neurobiology Division, has visualized an AMPA receptor with two different auxiliary subunits, a specific combination that is enriched in the hippocampus and involved in learning and memory.