Memory is a central function of the brain and is essential to everyday life. Recently, our lab developed a novel genetic approach that allows us to visualize cells in the mouse brain that store one memory trace, known as memory engram cells. This image represents two-memory cell populations labeled with green and red proteins respectively in the emotional center of the brain, the amygdala. By understanding the contribution of brain cells that store a single memory trace, we hope to provide insights into how humans form and recall memories with high accuracy.