Secret to lifelong memories sticking is molecular 'glue'
S ome memories last a lifetime — and now, scientists have revealed a type of molecular "glue" that helps those memories stick around. Memories form when collections of neurons in a region of the brain called the hippocampus activate in response to a particular experience. Each time you recall that experience, the same set of cells activates. When one neuron repeatedly activates another, the connection between those neurons strengthens. Over time, this process in the hippocampus, along with related activity in other regions of the brain, solidifies a short-term memory into a long-term one. To maintain these long-term memories, brain cells make proteins that help strengthen the connections, or synapses, between neurons. One critical protein is the enzyme PKMzeta, which is continually made by neurons. However, an outstanding question is how this enzyme "knows" to go to the right synapses to ensure that certain memories stay with us forever. In a new study, scientists