In neurons, changes in the size of dendritic spines—small cellular protrusions involved in synaptic transmission—are thought to be a key mechanism underlying learning and memory. However, the specific way in which these structural changes occur remains unknown. In a study published in Cell Reports, researchers from Nara Institute of Science and Technology (NAIST) have revealed that the binding of cell adhesion molecules with actin, via an important linker protein in the structural backbone of synapses, is vital for this process of structural plasticity.