Medical Research Council - London Institute of Medical Sciences

Now in our 9th year of bringing you beautiful imagery from biomedical science every day

Snapping Brain Activity
13 March 2015

Snapping Brain Activity

The brain is the most fascinating and mysterious organ of all. To understand how it works neuroscientists need to figure out which brain cells (neurons) are active during each of our behaviours: laughing, dancing, eating breakfast, the lot. It’s a daunting task, but detecting brain cell activity with chemical sensors – like the one used in the zebrafish pictured – are making things easier. This fish was genetically engineered to express a protein that glows magenta irreversibly when it both binds calcium (which increases inside active brain cells) and when exposed to violet light. Why does the light matter? Because switching on and off the light enables the neurons active at that moment, and only those neurons, to be permanently set to glow. In this fish, for example, the glowing magenta neurons were those cells that were active during a few seconds of violet light exposure when the fish was swimming about.

Written by Ruth Williams

Search The Archive

Submit An Image

What is BPoD?

BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.

Read More

BPoD is also available in Catalan at with translations by the University of Valencia.