Hebb’s law is simple: cells that fire together, wire together. …Within the brain are some 100 billion neurons, each capable of synaptic connection with 60,000 to 100,000 other neurons- a tremendous organization of neuronal networks with an almost infinite potential. There are particular laws which govern this organization. Hebb’s law is one of them.
If the cells are already weakly connected when they fire together, the synapse between them will be strengthened. Neural firings gather all aspects of experience together into an neural assembly that is encoded in memory. It is believed that the firing IS the memory. This activity-dependent wiring together is the basic mechanism for all learning and adaptation. With new learning comes the growth of new neurons and the branching of dendrites that allow the brain to change and expand the established connections among existing neurons.
(HEALING DEVELOPMENTAL TRAUMA, Laurence Heller and Aline LaPierre)