Scientists from the Salk Institute for Biological Research conducted a study and found that the neurons in the worm’s brain are activated by the smell of salt. Scientists observed 48 worms under a microscope and their brains react to sodium chloride (salt). When the worm’s brain was exposed to salt, a burst of activity was observed first in the sensory neurons, and after 30 seconds it spread to the rest of the neurons.

The researchers inserted a fluorescent sensor into the brain of the microscopic worm Caenorhabditis elegans that would light up when neurons were active.

“This may be because salt is bacteria that feed the worm,” suggests lead author Shrikanta Chalasani. He is interested in how the brain responds to stimuli at the cellular level.

Researchers cannot simultaneously track the activity of each of the 86 billion brain cells of a living person, but they can record it in a worm, because there are only 302 neurons in the worm’s brain. Such an experiment is still impossible to carry out, not only on the human brain, but even on the mouse.

The scientists plan to continue their research with other chemicals, targeting the brains of tiny worms to better understand all brain functions.

The study was published in the journal PLOS Computational Biology.