Scientists have developed a wireless device that can stimulate the brain with electric current, potentially delivering fine-tuned treatments to patients with diseases like epilepsy and Parkinson’s.

The neurostimulator, named the WAND, works like a “pacemaker for the brain,” monitoring the brain’s electrical activity and delivering electrical stimulation if it detects something amiss, said researchers at the University of California, Berkeley in the US.

These devices can be extremely effective at preventing debilitating tremors or seizures in patients with a variety of neurological conditions, according to the study published in the journal Nature Biomedical Engineering.

However, the electrical signatures that precede a seizure or tremor can be extremely subtle, and the frequency and strength of electrical stimulation required to prevent them is equally touchy.

It can take years of small adjustments by doctors before the devices provide optimal treatment.