Monkeys have been trained to control a virtual arm and experience virtual touch in a breakthrough that could help paralysed people.

In an experiment at Duke University, two rhesus monkeys were trained to operate a virtual arm with their brainpower and were able to distinguish the textures of objects it touched through electrical signals sent to their brains.

Scientists hope the discovery will help the development of a "robotic exoskeleton," a technology which could help quadriplegic patients not only regain movement but a sense of touch as well.

"Someday in the near future, quadriplegic patients will take advantage of this technology not only to move their arms and hands and to walk again, but also to sense the texture of objects placed in their hands, or experience the nuances of the terrain on which they stroll with the help of a wearable robotic exoskeleton," said Miguel Nicolelis, co-director of the Duke University Centre for Neuroengineering in Durham, N.C.

"It provides us with the demonstration that we can establish a bidirectional link between the brain and an artificial device without any interference from the subject's body," he said.

The researchers trained the monkeys, named Mango and Tangerine, to play a video game using a joystick and capture three identical targets, all using the virtual arm. Each target was associated with a different vibration of the joystick.

One of the monkeys needed only four attempts before it learned to select the correct object in the test.

The Walk Again Project, led by the Duke Centre for Neuroengineering, hopes to carry out a public demonstration of a robotic exoskeleton at the opening game of the 2014 Football World Cup in Brazil.