Investigating the deepest regions of a person’s brain is no easy task. Tiny robots crawling through it could help.
It’s a tantalising idea, but one problem is how to direct such nanobots on their travels. One way to do this would be to program them to search like bats hunting for prey, says a team who have created a computer simulation of this, and hope to trial their method in people in a couple of years.
Engineers around the world are working on various designs of nanobot, particularly ones that could release medicines inside the body. Panagiotis Katrakazas at the National Technical University of Athens, Greece, is more interested using them to detect brain damage, which can occur deep in the brain and be difficult to see in brain scans.
“The idea would be to inject nanobots to pinpoint the exact location of damage, which could then be targeted with medicine or surgery,” Katrakazas says. His team are working to develop nanobots that crawl along neurons, pinching them to see if they are healthy or not – healthy ones respond with an electrical signal, but damaged ones do not, he says.
But one of their greatest challenges is getting the nanobots to move in a coordinated manner. Katrakazas have turned to algorithms that describe bat swarming behaviour – created by other researchers from the acoustic signals bats emit to navigate and find prey. His team have adapted these algorithms for an EEG-like device, which can sit on a person’s head and emit acoustic signals in a similar pattern.
The team hope this pattern of signals can direct their nanobots on a route through the brain. Testing this approach using a simulation, the team found that just four bots would be needed to find a small tumour within a matter minutes, Katrakazas told the IEEE Engineering in Medicine and Biology Society meeting in Orlando, Florida, last month.
Still, the team have a long way to go before testing these bat-like nanobots in human brains. For a start, it is not clear what technology could enable such tiny devices to sense and transmit these acoustic signals, says Roderich Gross at the University of Sheffield, UK.
Katrakazas says he still hopes to have a system ready to trial in people within a few years. “Some doctors are interested in it,” he says.