Brain probe to replicate features of wood-boring wasp

A new insect-inspired design for neural probes could help counter the effects of diseases such as Parkinson’s without risking further brain damage.

Scientists at Imperial College London and the Micro and Nanotechnology Centre (MNTC) are developing microscopic anchoring hooks based on features of wood-boring wasps, which will be integrated into medical implants.

The research, carried out at the Science and Technology Facilities Council (STFC) Rutherford Appleton Laboratory (RAL) in Harwell, could improve electrical brain stimulators that are used to help sufferers of central nervous systems disorders.

The mechanical hooks are based on the teeth-like microstructures on the surface of the wasp’s sting that help it drill into wood. Once the probe is inserted into the brain, the hooks can be adjusted, changing their angle so they prevent the probe from moving.

Millimetre-wide deep brain stimulation (DBS) probes are currently inserted through the skull to place electrodes at very specific points in the brain, but there is a danger that the probe may move around and cause damage.

MNTC researcher Andreas Schneider said: ‘When you implant these currently, the electrode can migrate just by the motion of the patient’s head. It is just held by the tissue and you have to put an anchoring mechanism in the skull.

‘But if we put a surface texture on the probe then its migration can be reduced. We want to use this surface just for anchoring so we want to have a mechanism to release the texture once the probe is in place.’

The work builds on a previous biomimetic project carried out by Imperial and MNTC that produced a novel way of inserting the probes into the brain by replicating the burrowing mechanism of the wood-boring wasp.

MNTC also has particular expertise in microelectromechanical systems (MEMS) where movable cantilevers play an important role and is using this to create the mechanism to activate and deploy the anchoring hooks once the probe is inserted.

The independent research was commissioned by the National Institute for Health Research (NIHR) – which funds research that benefits the NHS – under its Invention for Innovation Programme.

Imperial College London plans to carry out a feasibility study to monitor how the mechanism will behave in the brain because the technology has not been applied to neural applications before.