Activated medial habenula neuron (IMAGE) Institute of Science and Technology Austria Caption A lunar surface-like electron microscopic image of an activated medial habenula neuron. SPO (light green), CAPS2 (dark blue), vesicles on the verge of releasing neurotransmitters (red), and the delimiting membrane (light blue). Credit © Koppensteiner et al./PNAS Usage Restrictions Free to use when reporting about paper License Original 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.