For a long time people have contemplated how powerful the human brain really is. This question might now have been answered in part, with a new technology linking brain power to computers. According to the BBC, new research shows that cursors on a computer screen have the ability to be controlled simply by certain thoughts. This is done by placing sensors directly on the surface of the Brain the technique is known as Electrocorticography. It is said to lead to better “brain-computer interfaces” for the disabled.
In many studies to do with brain power in recent years, electroencephalograph, or EEG was used. In these studies a device shaped as a cap was worn, with electrodes that pick up the electric fields produced by firing neurons. It has shown to control electric wheelchairs and toys based purely on the participants Brain power.
However, a problem has been detected with EEG. Lead author of the study, Eric Leuthardt, explains how EEGs lose a large amount of the important information that is available closer to the brain itself. "You cannot get the spatial or the signal resolution," he told BBC News. "One of the key features in signal resolution is seeing the higher frequencies of brain activity - those higher frequencies have a substantial capability of giving us better insights into cognitive intentions, and part of the reason EEG suffers for this is it acts as a filter of all of these high frequency signals." The EEG picks up signals outside the skull, which absorbs and muddle the signals, making the technique less viable than electrocorticography.
In comparison, electrocorticography taps directly into the brain's cortex. A surgical procedure is needed to implant a plastic pad containing a number of electrodes under the skull. Its use has already been shown by enabling people to play video games with their thoughts alone, but in this new study, the researchers have been able to use the speech networks of the brain to control movement.
"We would want to facilitate somebody's ability to communicate by having different phonemes - or essentially key presses - that could allow them to have discrete type of control."
When the four patients who were undergoing the eletrocorticography were asked to think of four different vowel sounds, "oo", "ah", "ee" and "eh", the high-frequency signals were displayed to accurately move a cursor on a computer screen.
"For a brain-computer interface, especially for someone who is severely impaired, they need something that is absolutely, completely reliable. If you think of EEG (systems), they move, they're susceptible to noise, and the likelihood for reliability is much lower."