We have witnessed the rapid growth of research in the field of brain-computer interface (BCI) in the last 15 years. This process now has the potential to further advance in terms of accuracy and speed through training and practice.
EEG-based BCI systems basically decode the user's neurophysiological intention signals and produce commands that can control an external device, such as computer applications, home appliances and prosthetic devices. A BCI includes a series of sensors for signal acquisition, a wired or wireless data transmission system and a processing component in order to perform data acquisition and analysis of brain activities as a means to create a direct communication channel between the brain and an external device.
The traditional wired BCI generally translates into a bulky, heavy system limiting the user's movement. However, the more recent advances in wireless transmission technology have offered the possibility of eliminating these limitations. This could lead to an improved feasibility of integrating the neurophysiological signals' acquisition, transmission and recording into electronic portable devices, such as smartphones and laptop computers.
Using these technological advances along with real-time embedded systems and signal processing techniques, it is now possible to design smaller, lighter, noninvasive, nontethered BCIs that can be easily worn.
There is a wide range of potential applications for wearable wireless EEG monitoring via BCIs. Some of these applications are monitoring of absence epilepsy, high-rate steady-state visual evoked potential-based BCI, multichannel telemetry system for signal-unit neuronal recordings, hybrid bioelectrodes for ambulatory EEG measurements using multichannel wireless EEG systems, and vibrotactile feedback for BCI operation.
Some of the recent wearable wireless BCI systems developed used dry microelectromechanical system EEG sensors, low-power signal acquisition, amplification, digitalization, wireless telemetry and online signal processing in order to increase usability, wearability, portability, reliability and in general to offer more practicality for the device.
The most important aspect in the development of new BCIs should be based on user needs. In a series of 205 studies and surveys, 96 percent of the low-function group had a strong interest in BCIs with emergency communication being the top priority.
According to these studies and the survey results, the most important design features voted for included:
- setup simplicity (no more than 10-20 minutes in length)
- high accuracy of up to 90 percent
- standby-mode error rate of no more than once every four hours
- speed of more than 20 letters per minute
- dry electrodes
In spite of all the ongoing research and new advances in this technology, it still has the potential for further advancements. Some the areas that can benefit from further research include improving signal quality (noise reduction techniques); more compact, lightweight miniaturized stylish designs; and more useful attractive applications for day-to-day life.
