Over time, the neurons in your brain are going to change. And that's only natural. When you experience a new event, your brain encodes the memory by altering the connections between neurons, which is caused by turning on several genes within these neurons. Recenty, a team of neuroscientists at MIT published their findings in the Dec. 23rd issue of Science in which the group was able to pinpoint some of the exact locations of memory formation within the brain. The team, led by Yingxi Lin, found that the Npas4 gene is especially active in the hippocampus, a brain structure known to be critical in forming long-term memories. Once engaged, the Npas4 gene turns on a series of other genes that modify the brain's internal wiring by adjusting the strength of synapses, or connections between neurons. The findings were obtained by studying the neural activity of mice which underwent mild electric shocks when they entered a specific chamber. Upon receiving the shock, researchers noted that Npas4 is turned on very early during this conditioning. The research is still in its early stages and while the researchers have identified only a few of the genes regulated by Npas4, they suspect there could be hundreds more that help with the memory formation process. The lesson learned: stick to it and if you have any questions, mildly shock some mice.