GCaMP8f indicator (VIDEO) Howard Hughes Medical Institute This video is under embargo. Please login to access this video. Caption Janelia scientists have developed new ultra-fast genetically encoded calcium indicators that can detect calcium ions nearly as fast as they are released from neurons. In this movie, ultra-fast jGCaMP8 indicators were used to track the response in L2 neurons that are part of the “off” pathway that detects changes in light intensity in the fruit fly visual system. The top image shows the changes in pixel intensity from L2 neurons as light is dimmed and brightened. When the light is turned off, the neurons depolarize, calcium concentrations increase and GCaMP fluorescence increases. When the light is turned on, the neurons hyperpolarize, calcium concentrations decrease and GCaMP fluorescence decreases. The bottom graph shows the mean change in intensity from the outlined region of interest. Credit Daniel Bushey Usage Restrictions Please use caption and credit provided. 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.