redletterdave points out work from Japanese researchers who produced an incredible visualization of how a brain perceives its environment. Studying zebrafish larvae, the scientists were able to observe neuronal signals in real time as the zebrafish saw and identified is prey, a paramecium. The results are illustrated in a brief video posted to YouTube, and in a longer video abstract hosted at Current Biology. (Direct download). The work is important because it demonstrates direct mapping of external stimuli to internal neuron activity in the optic tectum.