Modifying the human body or enhancing our cognitive abilities using technology has been a long-time dream for many people. An increasing amount of research tries to link the human brain with machines allowing humans to control their environment through their thoughts. Research on BCIs began in the 1970s, but it wasn't until the mid-1990s that the first working experimental implants in humans appeared. Following years of animal experimentation, early working implants in humans now exist, designed to restore damaged hearing, sight and movement. The common thread throughout the research is the remarkable cortical plasticity of the brain, which often adapts to BCIs, treating prostheses controlled by implants as natural limbs. With recent advances in technology and knowledge, pioneering researchers could now conceivably attempt to produce BCIs that augment human functions rather than simply restoring them, previously only the realm of science fiction.
2. Brain Machine Interface (Brain Computer Interface):
In this definition, the word “brain” means the brain or nervous system of an organic life form rather than the mind. “Computer” means any processing or computational device, from simple circuits to silicon chips (including hypothetical future technologies such as quantum computing). A Brain Machine Interface (BMI), sometimes called a Direct Neural Interface or a Brain Computer Interface, is a direct communication pathway between a human or animal brain (or brain cell culture) and an external device. In one-way BCIs, computers either accept commands from the brain or send signals to it (for example, to restore vision) but not both. Two-way BCIs would allow brains and external devices to exchange information in both directions but have yet to be successfully implanted in animals or human.
Brain-computer interface (BCI) is collaboration between a brain and a device that enables signals from the brain to direct some external activity, such as control of a cursor or a prosthetic limb. The interface enables a direct communications pathway between the brain and the object to be controlled. In the case of cursor control, for example, the signal is transmitted directly from the brain to the mechanism directing the cursor, rather than taking the normal route through the body's neuromuscular system from the brain to the finger on a mouse. By reading signals from an array of neurons and using computer chips and programs to translate the signals into action, BCI can enable a person suffering from paralysis to write a book or control a motorized wheelchair or prosthetic limb through thought alone. Current brain-interface devices require deliberate conscious thought; some future applications, such as prosthetic control, are likely to work effortlessly. One of the biggest challenges in developing BCI technology has been the development of electrode devices and/or surgical methods that are minimally invasive. In the traditional BCI model, the brain accepts an implanted mechanical device and controls the device as a natural part of its representation of the body. Much current research is focused on the potential on non-invasive BCI. At the European Research and Innovation Exhibition in Paris in June 2006, American scientist Peter Brunner composed a message simply by concentrating on a display. Brunner wore a close-fitting (but completely external) cap fitted with a number of electrodes as shown in fig. Electroencephalographic (EEG) activity from Brunner's brain was picked up by the cap's electrodes and the information used, along with software, to identify specific letters or characters for the message.
The BCI Brunner demonstrated is based on a method called the Wadsworth system. Like other EEG-based BCI technologies, the Wadsworth system uses adaptive algorithms and Pattern-matching techniques to facilitate communication. Both user and software are expected to adapt and learn, making the process more efficient...