The way the brain-computer interface or BCI works

The way the brain-computer interface or BCI works 

The brain-computer interface, or BCI, is a technology that communicates directly with the brain and a device in the external environment of the brain. It is also known as Brain Machine Interface (BMI) or Neural Interface. It is possible to apply this technology in various important fields like increasing human efficiency. Brain-computer interface technology has the potential to change the world. 

Post Index:

1. Strategies for measuring brain activity 

2. The EEG-based brain computer interface is a neural process

3. Application of artificial intelligence for EEG based brain-computer interface

4. Application of EEG-based brain-computer interface

At the initial stage, 3 elements are required for the formation of BCI: 

1. Specific electrodes to record the electrical, magnetic, and metabolic activity of the brain.

2. A processing pipeline to interpret signals received from the brain. It selects the necessary signals from the brain and from there gives instructions regarding the interpretation and results of the required types.

3. A computer that works according to the instructions given.

The brain has a number of instruments that can be controlled using instructions. These 5 tools can be used to replace, rehabilitate, enhance, support or improve human performance. 

Strategies for measuring brain activity 

The first step in BCI technology is to properly capture the signals transmitted from the human brain. This step is the most important. Because at this stage it is possible to determine the cost of the whole process, the potential application area and what part of the population it can be used for. There are two ways to understand the functions of the brain. The first is by replacing sensors inside the body and the second is by placing sensors outside the body.

By replacing sensors inside the body, it is possible to get a very clear idea of ​​the electrical activity of the brain based on space-time.

That is, we can know exactly where, when, and how the nervous activity of the brain is taking place. However, this procedure is quite expensive and requires complex surgery to replace the sensors inside the body. There are also potential health risks after surgery.

Electroencephalography or EEG with sensors placed outside the body makes it possible to detect electrical activity of the brain, magnetic action by magnetoencephalography (MEG) and spectroscopy of short-wavelength effective infrared ray spectroscopy. 

The EEG-based brain computer interface is a neural process 

It is possible to determine the electrical activity inside the brain by placing electrodes in different places above the skull. At least 2 electrodes are used for this purpose, of which the voltage of the rest of the electrodes is measured with respect to one specific electrode.

The electrical activity of the brain is measured according to the voltage differences between the different electrodes. In order to measure the electrical work of a particular place in the brain, the electrodes have to be placed as close as possible to that particular place in the brain. As a result, different types of neurological activity can be measured by placing electrodes in different places of the skull.

It is possible to diagnose different types of active brain activity through EEG. The activities that the brain automatically performs without any significant stimulation of the external environment are spontaneous functions of the brain. On the other hand, the brain performs a variety of functions in response to any sensation, event, or stimulus in the external environment. 

Application of artificial intelligence for EEG based brain-computer interface 

The development of artificial intelligence systems is playing a significant role in the storage and use of EEG-based information.

In fact, to control a device, the value of the voltage determined by the electrodes used in the EEG-based BCI method has to be converted to digital command. The brain computer interface requires an algorithm that can process signals from the brain to connect the brain and the device. At the same time it can bring out different features of the brain and recognize different types of patterns. And all this can be done through proper AI. 

Application of EEG-based brain-computer interface 

People who have lost normal function due to an accident or illness can carry out their daily activities using BCI. Anyone who cannot walk can drive a robotic wheelchair by BCI. Or someone who is dumb can use a brain-controlled communication device.

In 2009, a team of BCI researchers from the University of Zaragoza invented a BCI-controlled wheelchair based on the P300 sample.

There, wheelchair users are shown 3D images of their surroundings in a random way. From the pictures they are instructed to fix their attention on a specific destination. After a few seconds, the wheelchair BCI system automatically activates users by analyzing their brain responses and stimuli, taking them to their desired destination.

It is also possible to regain the lost performance of the body through BCI. Anyone who suffers from paralysis or weakness of the limbs due to a nervous injury can control their movement through the BCI's electrical stimulation. 

These two types of BCI applications work to help people with physical disabilities. But healthy people can also benefit from BCI. However, the role of BCI in improving or assisting people's performance is not yet discussed. Because, while it is easily accepted with the help of disabled or weak people, there are moral concerns and debates about the use of BCI in controlling the performance of normal people and conducting activities.

Research papers and research data are constantly being published from more and more laboratories due to the global open science initiative.

At present, therefore, the mechanical advancement of the BCI system and the development of working methods are becoming more and more possible without the very expensive equipment of EEG recording.