Possibilities of Direct Mind Interface

How to have a direct interface with the mind? There are a number of current ways to assess the activities of the brain (see Table) or perhaps a completely new method will be developed.  There is also the possibility of more invasive methods such as placement of electrodes in the brain.  This is perhaps exemplified in the cochlear implant to correct human deafness .

The methods that have good spatial resolution, which image blood volume and oxygen saturation, are slow after the fact measure of brain activity.  While methods that have good temporal resolution usually have poor spatial resolution.  There are two methods that may have good spatial resolution and temporal resolution - but the brain has very weak signals of these.  These two methods are magnetic fields and the event related optical signal.  There is another possibility but little is know about it yet, and that is fMRI of detect signals from sodium, phosphorus, carbon, nitrogen and oxygen the metabolic building blocks of brain function and human thought.  The first instrument in the world to do this is being built in its own building at the Center for MR Research at the University of Illinois at Chicago using the largest magnet field for MRI of 9.4 Tesla, which is 100,000 times the Earth's magnetic field.

For every electrical field there is a corresponding magnetic field.  All the electrical fields in the brain have a corresponding magnetic field.  These magnetic fields are very weak and require very sensitive means to measure them.  Special detectors called superconducting quantum interference devices (SQUIDs), cooled to the temperature of liquid helium (about -273°C), can measure these tiny magnetic fields.  With sophisticated electronics and software, the outputs of the SQUIDS are used to localize the source of the brain activity within millimeters. The resulting functional brain data may then be overlaid on an anatomical image produced by, for example, an MRI.

Near-infrared light (NIR) can penetrate the brain to sufficient depths so as to allow functional mapping. Changes in tissue oxygenation associated with brain activity modulate the absorption and scattering of these NIR photons. By measuring the optical changes at various wavelengths in the NIR band qualitative measures of brain activity can be obtained.  The NIR response in the brain is comprised of two signals. There is a slow response (approx. 5-8 s) as a result of attenuation changes due to localized blood volume and oxygenation changes and a fast response (of the order of 50 - 300 milliseconds) perhaps due to changes in the scattering properties of the neuronal membranes during firing. This EROS (Event Related Optical Signal) is more directly related to neural activity and may correlate with EEG activity.  However, present instruments must average 1000 trials or more to bring the signal out of the noise.

Use Your Mind for Control of Electronic Devices

NeuroSky, a fabless semiconductor/module company, has developed a non-invasive neural sensor and signal processing technology that converts brainwaves and eye movements into useful electronic signals to communicate with a wide range of electronic devices, consoles, and computers.  Which means being able to control all manner of gadgetry with your brain. NeuroSky claims they are already in talks with mobile phone and gaming companies to use their technology, which combines low-cost active sensors and a signal-processing module for interpreting your brainwaves.  Whether or not this technology is yet to be seen.

BBCI — An interface between brain and computer

Fraunhofer, a German company, has developed the Berlin Brain Computer Interface (BBCI) that lets a person control a mouse cursor on a personal computer screen.  A cap studded with electrodes records cerebral electric activity (EEG) of a person.  These signals are amplified and transmitted to the computer, which transforms them into device control commands. The crucial requirement for the successful functioning of the BBCI is that the electric activity on the scalp surface already reflects motor intentions, i.e., the neural correlate of preparation for hand or foot movements. The BBCI detects the motor-related EEG changes and uses this information to perform a choice between two alternatives: the detection of the preparation to move the left hand or the detection of the preparation to move the right. The BBCI makes it possible to operate devices that are connected to the computer; and the computer could be interface to further devices - even via the internet.

Laboratory of Computational Engineering's Brain Computer Interface

Laboratory of Computational Engineering (LCE) at the Helsinki University of Technology in Finland has developed a Brain Computer Interface (BCI) that enables the motor-disabled and also healthy individuals to operate electrical devices and computers directly with their brain activity. Their BCI recognizes and classifies different brain activation patterns associated with real movements and movement attempts made by an individual.

The user has an electroencephalography (EEG) cap on and by thinking about left and right hand movement the user controls the virtual keyboard with her brain activity.  LCE has concentrated on motor cortex activity.  They measure the electric activity of the brain using EEG. They also have also examined the feasibility of using magneto-encephalography for BCI.

Devices to Read Brain Signals Show Promise to Help Severely Paralyzed

Neuroscientist Jonathan Wolpaw has been using a computer and a stretchy red cap to read people's minds.  Currently, with the help of medical engineers in Boston, Wolpaw is trying to convert his cumbersome laboratory apparatus into a household medical device for people so severely paralyzed they can't move even an eyelid.

Wolpaw is a pioneer of ''brain-computer interface research," the science of picking up the brain's electric signals and translating them into information that can tell a device what to do. Week after week, volunteers in his Upstate New York public health laboratory put on a nylon mesh cap studded with electrodes and nudge a cursor around a computer screen simply by thinking.

In the past nine months, engineers working with Wolpaw have streamlined the cap's design, found less expensive amplifiers, and developed a useful menu of icons that could allow the user to ask for medical help, control lights, or watch television. Their goal is to devise a system that costs less than $5,000, with a cap that's comfortable to wear not just for a short lab session, but for hours at a time.

Cythor: bringing the ultimate interface into your life