Researchers may have found a way to ‘inject’ information directly into the brain.
In a new study, a team of neuroscientists has shown that delivering tiny electrical currents to the premotor cortex of monkeys can essentially provide ‘instructions’ that guide their movements.
While the research is still in the early stages, the experts say this could pave the way for treatments to help people who have lost some brain function after a stroke or injury.
At the start of the experiment, the monkeys grasped a handle in a central position. Then, based on which lights turned on, they would manipulate the objects with their hands. As the lights were switched on, the team also administered low levels of electrical stimulation
‘Researchers have been interested primarily in stimulating the primary sensory cortices – the somatosensory cortex, visual cortex, and auditory cortex – to input information into the brain,’ said senior author Marc H. Schieber, a physician and researcher at the University of Rochester.
‘What we are showing here is that you don’t have to be in a sensory-receiving area in order for the subject to have an experience that they can identify.’
In the new study, published to the journal Neuron, the team trained two rhesus monkeys to execute tasks based on visual instructions and movement.
The monkeys were presented with four objects, which were each surrounded by a light that could be switched on or off.
At the start of the experiment, the monkeys grasped a handle in a central position.
Then, based on which lights turned on, they would manipulate the objects with their hands.
As the lights were switched on, the team also administered low levels of electrical stimulation to the monkeys’ premotor cortex.
The researchers used a different point of stimulation in the brain for each of the four lights and movements.
Then, the lights were taken away.
After doing this, the team found that the monkeys were able to carry out the correct movements based only on the microstimulation.
‘The monkeys can’t tell us what they are feeling, so training them to associate the microstimulation with a movement is the way we are able to confirm that they have felt an urge or had some kind of experience,’ Schieber says.
Previous research has shown that stimulation can trigger a response in the arms and hands.
In the new study, published to the journal neuron, the team trained two rhesus monkeys to execute tasks based on visual instructions and movement. Stock image
To ensure that this wasn’t the case in the new experiments, the researchers changed the location assignment of the electrodes, and retrained the monkeys with the lights.
And, they found that the monkeys were able to associate the different areas of stimulation with the reassigned movements.
The study could pave the way for better brain-computer interfaces and neuroprosthetics, the team says.
‘Most of the work in the development of brain/computer interfaces has focused primarily on the sensory area of the brain,’ said lead author Kevin A Mazurek, a postdoctoral fellow in Schieber’s lab.
‘But that confines where in the brain you’re able to deliver the information.
While the research is still in the early stages, the experts say this could pave the way for treatments to help people who have lost some brain function after a stroke or injury. Stock image
‘In this study, we show you can expand the neural real estate that can be targeted with therapies. This could be very important for people who have lost function in areas of their brain due to stroke, injury, or other disease.
‘We can potentially bypass the damaged part of the brain where connections have been lost and deliver information to an intact part of the brain.’
Moving forward, the researchers say the technique could be tried in humans.
‘When you stimulate the somatosensory or visual cortex directly, the subject typically feels something on their skin or sees something in their vision,’ Schieber says.
‘This shows you may be able to deliver the desired information to a person’s brain without these perceptions.’