I always have the respect, the interest and the awe towards neural system, due to its amazingly agility and robustness. This is possibly the reason why I took over a year to get hands-on experience with Neuroscience and sensory system.

The long-existed unsolved question, that whether Drosophila could distinguish amino acid with their gustatory system, interested me as I was wondering how organs as simple as sensilla, could recognize so many chemicals. After six-month struggling with electrophysiological recordings I found several interest facts: first, the responses to different chemicals on the same sensilla are different, and the responses to the same chemical on different sensilla are different, conferring diversified coding strategies that can tell the difference between different chemicals. Second, when doing single-sensilla recording experiments, the result was fluctuated—or unstable—yet the result became stable when it came to behavior level, which indicated that the eventual decision is made on the calculation of inputs into many sensilla instead of the only sensilla that gave positive response. 

All these interested findings pointed to the importance of hierarchical coding in building robust systems.