26 May 2023

Paralysed Man Walks Using the Brain-Spine Interface

Twelve years ago, a cycling accident left Gert-Jan Oskam, now 40, with paralysed legs and partially paralysed arms, after his spinal cord was damaged in his neck. But these days, he is back on his feet and walking, thanks to a brain-spine interface. Oskam was one of the participants in that trial, but after three years, his improvements had plateaued. The new system makes use of the spinal implant that Oskam already has, and pairs it with two disc-shaped implants inserted into his skull so that two 64-electrode grids rest against the membrane covering the brain.

The skull implants detect electrical activity in the cortex, the outer layer of the brain. This signal is wirelessly transmitted and decoded by a computer, which then transmits the information to the spinal pulse generator. After around 40 rehabilitation sessions using the brain-spine interface, he had regained the ability to voluntarily move his legs and feet. That type of voluntary movement was not possible after spinal stimulation alone and suggests that the training sessions with the new device prompted further recovery in nerve cells that were not completely severed during his injury.

More information:

https://www.nature.com/articles/d41586-023-01728-0

24 May 2023

Twisting Bee Robot

A robotic bee that can fly fully in all directions has been developed by Washington State University researchers. With four wings made from carbon fiber and mylar as well as four light-weight actuators to control each wing, the Bee++ prototype is the first to fly stably in all directions. That includes the tricky twisting motion known as yaw, with the Bee++ fully achieving the six degrees of free movement that a typical flying insect displays. To allow their robot to twist in a controlled manner, the researchers took a cue from insects and moved the wings so that they flapped in an angled plane.

They also increased the number of times per second their robot can flap its wings, from 100 to 160 times per second. Part of the solution was the physical design of the robot, using a new design for the controller. Weighing in at 95 mg with a 33-millimeter wingspan, the Bee++ is still bigger than real bees, which weigh around 10 milligrams. Unlike real insects, it can only fly autonomously for about five minutes at a time, so it is mostly tethered to a power source through a cable. The researchers are also working to develop other types of insect robots, including crawlers and water striders.

More information:

https://techxplore.com/news/2023-05-bee-robot.html

22 May 2023

Distinguish Among Hand Gestures Using BCI

Researchers from University of California San Diego have found a way to distinguish among hand gestures that people are making by examining only data from noninvasive brain imaging, without information from the hands themselves. The results are an early step in developing a non-invasive brain-computer interface that may one day allow patients with paralysis, amputated limbs or other physical challenges to use their mind to control a device that assists with everyday tasks.

The researchers underscored the advantages of MEG, which uses a helmet with embedded 306-sensor array to detect the magnetic fields produced by neuronal electric currents moving between neurons in the brain. Alternate brain-computer interface techniques include electrocorticography (ECoG), which requires surgical implantation of electrodes on the brain surface, and scalp electroencephalography (EEG), which locates brain activity less precisely.

More information:

https://today.ucsd.edu/story/new-study-shows-noninvasive-brain-imaging-can-distinguish-among-hand-gestures