Redesign brings interface into the mainstream

Cambridge Consultants is providing key technology behind a novel brain-computer interface (BCI) device that translates brain waves into computer control commands.

Cambridge Consultants is providing key technology behind a novel brain-computer interface (BCI) device that translates brain waves into computer control commands - without the need for electrodes implanted in the brain.

This represents a breakthrough in the way computers can assist patients in their daily activities.

The BCI system is being developed by the Wadsworth Center, a public health laboratory for the New York State Department of Health, to help even individuals who are completely paralysed to communicate with the outside world.

The Wadsworth Center's BCI system has been proven to match the capabilities of costly invasive systems that require surgery to implant electrodes in the brain - and should be able to help individuals who have lost all muscular control, something other augmentative or assistive communications approaches such as eyeball-tracking systems cannot.

Cambridge Consultants helped the Wadsworth Center transform a brilliantly engineered and technically complex research equipment into an easy-to use, more portable system suitable for patients and their caregivers - one that can be produced at a fraction of the cost.

Field testing of the enhanced BCI system began last month, with up to 10 persons scheduled to receive the system for use at home or in hospitals by June 2006.

"Our device requires neither implanted electrodes nor eye movement to help severely paralysed individuals to communicate", said Dr Jonathan Wolpaw, Director of the BCI unit of the Wadsworth Center.

"We're extremely grateful to Cambridge Consultants for helping us to make our technology more easily usable by nontechnical caregivers outside a lab setting, with readily accessible PCs and components".

"We're trying to take a solution that might cost tens of thousands of dollars and make it work better at a price of around $5000".

"We hope to be able to share more about our early patient studies shortly".

For years, brain-computer interface technology has excited researchers as a direct way to harness the human brain for controlling the body and the devices we manipulate.

In the near term, this technology can give individuals suffering from conditions such as ALS (amyotrophic lateral sclerosis, also known as Lou Gehrig's disease), or brainstem strokes, the ability to communicate.

These individuals face huge challenges in communicating and may even be entirely 'locked in' to their bodies, possessing no muscle control of any type.

Future iterations of the BCI technology hold the potential for controlling medical devices such as wheelchairs and prosthetic limbs.

There is also great interest in applications where streamlined communications are essential such as military pilots activating jet defensive mechanisms.

The challenge has remained to deliver BCI systems that are accurate, yet affordable and easy to use.

The Wadsworth Center BCI system consists of three primary hardware components and specialised software.

A mesh cap holds small sensor electrodes firmly against the user's head.

An amplifier is connected to the electrodes and is used to boost the minute analogue signals (measured in microvolts) received from the surface of the scalp into a more robust signal, which is then converted into a digital signal and analysed by specially designed signal processing software running on a PC.

Two monitors are connected to the PC, one for the caregiver interface and one for the user interface.

The Wadsworth Center won the prestigious Altran Foundation for Innovation award in 2005 for its use of technology to overcome social exclusion.

As part of the award, Cambridge Consultants, a company in the Altran group, is providing its expertise to the BCI group.

Cambridge Consultants helped Dr Wolpaw's group transform its research-based system, with its inherently technically demanding interface, into a system capable of daily use by nonscientists.

One of the hurdles included developing a sensor cap that was comfortable enough for extended wear, yet allowed an untrained caregiver to position the sensors accurately on the head.

Positioning deviations from session to session of more than a few millimetres can dramatically affect the accuracy of the system.

Cambridge Consultants is pursuing several alternative sensor cap designs to make them more ergonomically comfortable for extended wear and to provide a less obtrusive appearance, without sacrificing repeatability and precision of sensor placement and signal reception.

The firm provided electronics hardware and software device drivers to link the BCI software with the hardware from several different manufacturers.

Cambridge Consultants also helped create a graphical software interface with icons and sound so that patients can more readily communicate with their caregivers.

For example, patients now can access icons for 'water' and 'food', and traverse a menu with a variety of choices by using their brain waves to transcend the language barrier.

Patients make selections in either of two ways.

In one, they pay attention to a particular icon displayed among many in a grid on the computer screen.

As the various icons flash in succession, a distinct electrical response is evoked in the brain by the attended icon.

The system tracks the timing of the flashes and the evoked response, identifies the attended icon and outputs the appropriate sound, text, and/or environmental control signal.

The system can also generate speech from those words created on computer, enabling users to communicate audibly with a caregiver if they choose.

In the second method, the user can imagine particular movements.

Even if the user is totally paralysed, this imagined action generates a localised electrical stimulus in the brain that can be detected by the BCI system.

The system then maps that action to moving the computer cursor in a particular direction.

In this manner, the user can navigate menu structures to select actions and/or perform word processing activities, similar to the way in which people normally use a computer mouse.

Future iterations will provide the ability to interface with environmental control systems to turn lights on and off or change the channel on a television as well as to communicate remotely with caregivers.

Additionally, Cambridge Consultants is developing software that will allow the BCI group to retrieve system-use data from users around the world.

With Cambridge Consultants' enhancements, the BCI system can be used by people speaking any language, as the system uses icons rather than text.

The software is provided free by the BCI group for noncommercial research uses and is powered by a standard laptop computer.

The sensor cap is being designed for ease of manufacture and low cost, and the hardware and software provided by Cambridge Consultants are allowing the BCI group to test amplifiers less expensive than those currently used with the system.

All of these changes are aimed at providing a system cost of less than $5000.

"Our mission is to turn promising lab technology into a comfortable device suitable for daily use, simplifying a sophisticated research device so that anybody with basic computer understanding can operate it", says Andrew Diston of Cambridge Consultants.

Diston continues: "Breakthrough technologies are created every day in labs".

"The art is to make innovations usable and affordable on a larger scale".

"We're delighted to be working in partnership with Dr Wolpaw and his team to let technology give a voice to patients who are most in need of one".

"This design work is well deserving of its numerous awards, and we believe it will vastly advance the applicability of BCIs across many other application categories".

Back to top