Zebra danio embryos are popular subjects in genetic experiments. © Adam Amsterdam

Japanese researchers have for the first time been able to record a real-time video of thought processes moving within a living animal’s brain, and the creature in question is a fish!

A paper published in the journal ‘Current Biology’ this week details how a special gene was inserted into a larva of the zebra danio, Danio rerio and an incredibly sensitive fluorescent probe used to detect neuronal activity.

The gene is known as GCaMP and it fluoresces in the presence of calcium ions, which also happen to be released during neuronal activity in the brain.

Using this technology scientists were able to map what happens in a zebrafish’s brain when it spots a potential prey item, in this case a paramecium swimming close to it, and make a visual recording of its mental reaction.

The result is a stunning video sequence in which the fish’s ‘thoughts’ can be seen bouncing around inside its brain as the paramecium moves and changes direction.

This will apparently prove a useful tool in studies of perception and potentially, aid development of psychiatric medications.

“In the future, we can interpret an animal’s behavior, including learning and memory, fear, joy, or anger, based on the activity of particular combinations of neurons,” said Koichi Kawakami of Japan’s National Institute of Genetics, and co-author of the paper.
For further information see the paper: Muto, A., M. Ohkura, G. Abe, J. Nakai and K. Kawakami. 2013. Real-Time Visualization of Neuronal Activity during Perception. Current Biology, 31 January 2013