I was fascinated by the acute and insightful observations of my mentor, Coby Schal, on how male cockroaches pursue females in the forest (Science 215, 1405–1407). Later, at Tsing Hua University, in trying to understand how the brain controls sexual behavior and reproduction, we serendipitously discovered that juvenile hormone synthesis in cockroaches is regulated by NMDA receptors. Knowing the importance of this molecule in learning and memory, I immediately realized that this would be a good chance to see if insects actually use the same molecules as humans to learn and remember. I wrote a letter to Coby asking for his advice.“Tim Tully at Cold Spring Harbor Laboratory has discovered dozens of memory genes in Drosophila. He will be the best person to address this question”, Coby said. During my first week at Cold Spring Harbor Laboratory, Tim Tully sparked my interest with his olfactory associative learning paradigm and sealed my commitment to mapping memory circuitry.