How does the brain regulate learning on a cellular level?

• Highlights
• Salk scientists find the brain regulates the density of synaptic vesicles in presynaptic terminals during long-term potentiation (LTP), a key mechanism of learning and memory
• The study uses novel 3D reconstructions and computer simulations to capture structural changes that were previously unmeasurable and predict that synaptic vesicles increase mobility during LTP
• These findings lay the groundwork for understanding how dysregulation of synaptic vesicle clusters may contribute to aging and neurological disease

LA JOLLA—Inside the brain is a dense network of neurons that receive, process, and relay information. The synapse, where neurons meet, is the epicenter of this communication. Neurons that send information, called presynaptic neurons, hold tiny packages of neurotransmitters—waiting for a chemical signal from the brain to be released. How this system is regulated by the brain during periods of learning has, until now, been out of reach.