14 DAY TRIAL // A team of investigators from the Berkeley Lab managed to get a unique insight into how the brain coordinates stimuli inputs from the body to make split-second decisions, and react, when following an object of interest
The work was conducted on zebrafish, which are oftentimes used as animal proxies for humans in such situations, due to the similarities their neural networks have to our own.
Researchers say that the world is full of danger and opportunity, and that it's the job of the brain to ensure that no harm comes to us. It does that by instantly processing stimuli it receives.
In the human brain, visual, auditory and tactile sense combine instantly to produce a map of the world around us, which enables us to steer clear of dangerous scenarios, elaborate fight or flight-type responses and take advantage of opportunities that are presented to us.
As the neural processing takes place, the brain also needs to classify a wide variety of information, and to prioritize which action is necessary and the most important, at any given time.
In order to gain a better understanding of how this happens, investigators at the US Department of Energy's (DOE) Lawrence Berkeley National Laboratory (Berkeley Lab) looked at the brains of zebra fish that were stocking their prey.
The group investigated single neurons in the brains of the animals. The nerve cells were located in an area of their brains called the optic tectum, which is responsible for receiving, filtering and relaying signals from the retina.
Following nearly-instant processing, the neural impulses are sent to areas of the brain involved in dictating and controlling motion, the team says.
Whenever the animals detected something that could be construed as prey lurking nearby, the output neurons in their optic tectum lit up like a Christmas tree. This pattern of activation then spread throughout the brain, prompting the zebrafish to literally spring into action.
“We can see, for the first time, how neurons in the fish’s optic tectum take visual information and convert it into an output that drives action,” explains Berkeley Lab Biosciences and Materials Sciences Division biophysicist Ehud Isacoff.
The expert also holds an appointment with the Department of Molecular and Cell Biology at the University of California in Berkeley (UCB).
Funding for this investigation came from the US National Institutes of Health’s (NIH) Nanomedicine Development Center for the Optical Control of Biological Function and from a grant secured under the Frontiers in Integrative Biological Research program of the National Science Foundation (NSF).
Video description: Short clip showing how the activation of neurons in the optic tectum of zebrafish stalking their prey.
Video credit: Berkeley Lab