Biosignal detection using BCI

Years into the history people might not have never thought of reading a human mind or interacting with the brain of a species.  Initiatives which predates upto 1970s has come up with initiatives towards reading bio signals emitted from a person. This is termed as mind-machine interface (MMI), direct neural interface (DNI), synthetic telepathy interface (STI), brain machine interface (BMI) and Brain Computer Interaction (BCI).

Biosignal is a kind of signal which can be found from in any biological being. Biosignals can be referred to both electrical and non-electrical signals which are generated from specialised tissue, organ or a cell system in a nervous system. The main types of signals which are considered when detecting bio-electrical signals are

• Electroencephalogram (EEG)
• Electrocardiogram (ECG)
• Electromyogram (EMG)
• Mechanomyogram (MMG)
• Electrooculography (EOG)
• Galvanic skin response (GSR)
• Magnetoencephalogram (MEG)

non-electrical signals that are capable of being detected are

• mechanical signals ( mechanomyogram)
• Acoustic signals
• Chemical signals
• Optic signals

Related to BCI approaches the main consideration from above signals are towards Electroencephalogram (EEG) and Magnetoencephalography (MEG).

 

EEG based BCI

Researchers and medical practitioners are concerned about providing non-invasive methods of implementing BCI devices and read the mind for enhanced solutions.  EEG has emerged as the mostly studied non-invasive method which also provides with ease of use, portability and low setup cost.

The main drawback of this approach is that it is more prone to disturbed with noise and also in-order to efficient results the users need to go through extensive training first.

The process of extracting, amplifying, classifying and getting feedback from EEG based BCI system is as below.

Figure 1 : EEG BCI process

EEG functioning devices

XWave headset

Figure 2 : XWave headset

NeuroSky MindFlex

 Figure 3 : NeuroSky MindFlex

MyndPlay Headband

Figure 4 : MyndPlay

EEG Examples

Figure 5 : EEG artefacts during a range of different tasks

MEG based BCI

It is a functional neuroimaging technique is also a non-invasive method to map brain activities using magnetic fields produced by the brain electrical currents in brain. Magnetometers are the key players in this technology. Since brain’s magnetic field is considerably lower than in the general atmosphere it requires a magnetic shielding in order to perform magnetoencephalography.

Brain Imaging,  changes in blood flow, creating functional maps of human cortex, pinpointing sources in primary auditory, somatosensory, and motor areas are the main applications of MEG BCI in computing.

Application Use of MEG to identify the aging of human brain

 

 Figure 6 : MEG to identify aging of human brain

 

Figure 7 : VectorView

Figure 8 : Brain Imagery generated with a MEG system

Referencess

• Brain–computer interface - Wikipedia, the free encyclopedia. 2014. Brain–computer interface - Wikipedia, the free encyclopedia. [ONLINE] Available at:http://en.wikipedia.org/wiki/Brain%E2%80%93computer_interface. [Accessed 28 April 2014].
• Mental health - Wikipedia, the free encyclopedia. 2014. Mental health - Wikipedia, the free encyclopedia. [ONLINE] Available at:http://en.wikipedia.org/wiki/Mental_health. [Accessed 28 April 2014].
• Emotion Recognition Based on Brain-Computer Interface Systems | InTechOpen. 2014. Emotion Recognition Based on Brain-Computer Interface Systems | InTechOpen. [ONLINE] Available at:http://www.intechopen.com/books/brain-computer-interface-systems-recent-progress-and-future-prospects/emotion-recognition-based-on-brain-computer-interface-systems. [Accessed 28 April 2014].
• . 2014. . [ONLINE] Available at:http://openi.nlm.nih.gov/imgs/512/28/3112189/3112189_pone.0020674.g001.png. [Accessed 28 April 2014].
• How does the brain change with age? Part #3: MEG brain waves - YouTube. 2014. How does the brain change with age? Part #3: MEG brain waves - YouTube. [ONLINE] Available at:https://www.youtube.com/watch?v=eq8wHT8qYJs. [Accessed 28 April 2014].
• Magnetoencephalography - Wikipedia, the free encyclopedia. 2014.Magnetoencephalography - Wikipedia, the free encyclopedia. [ONLINE] Available at: http://en.wikipedia.org/wiki/Magnetoencephalography. [Accessed 28 April 2014].
• EEG artefacts during a range of different tasks - YouTube. 2014. EEG artefacts during a range of different tasks - YouTube. [ONLINE] Available at:https://www.youtube.com/watch?v=u8WgWWJueSc&list=PLWnTQ-kqjDMX6CSlnBvsTt0gHQ7J4L0S7. [Accessed 28 April 2014].