Study: Botulinum toxin can spread from the face to the brain

Pisa, Italy

- A study testing the effects of botulinum toxin injected into the whisker muscles of rats showed traces of the toxin in the rodent's brain stem three days later, Daily Mail reports.

The findings, published in the latest issue of the Journal of Neuroscience, showed the toxin was still present six months later, and that it also moved from one hippocampus, which controls long-term memory and spatial navigation, to the hippocampus on the other side of the rat's brain, researchers report.

Despite the findings, scientists say more research is necessary, as rats and humans have a different physiology and respond differently.