Brain Activity (IMAGE) Technical University of Munich (TUM) Caption Image of a Drosophila brain: Magenta indicates uninvolved synapses in the fly's brain. The green highlighted neurons use the messenger octopamine to transmit signals from the fly's brain stem. The green and white colors thus show signaling pathways in the fly's brain. Credit Anja Friedrich / TUM Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.