Scientists have come up with a new method to record 3D video of neural activity in approximately the entire brain of a free-moving animal. It is an advance that may help scientists better understand how neurons organize action and perception in animals.

The US’s Princeton University researchers used the technique to record the first 3D recordings of neural activity in the nematode Caenorhabditis elegans. Nematode Caenorhabditis elegans is a 1 millimetre long worm species with a nervous system that has just 302 neurons.

The researchers correlated the activity of 77 neurons from the nervous system of the animal with specific behaviors, like turning and backward or forward motion.

Andrew Leifer, from Princeton's Lewis-Sigler Institute for Integrative Genomics said that work linked to neuron activity that has been done previously, either focused on brain’s tiny sub-regions or was based on observations of organisms that were somehow limited in mobility or were unconscious.

Leifer said that the system has provided the most detailed picture so far of brain-wide neural activity with single-neuron resolution in a free-moving animal.

The infinitesimal arrangements of chemical signals and electrical impulses that can contain billions of cells, as in humans, are called neural networks.

For the instrument, the simple nervous system of C elegans gave a more manageable testing ground.

Leifer added that performing whole-brain recordings in humans would be immensely difficult. He mentioned, “The technology needed to perform similar recordings in humans is many years away. By studying how brain works in simple animal like worm, however, we hope to gain insights into how collections of neurons work that are universal for all brains, even humans”.