Vision Device Converts Video Data into Electric Patterns on Small Metal Plate:
The BrainPort V100, developed by Wicab, Inc. (Middleton, WI) is a non-surgical assistive vision device designed to help people with little or no functional vision with orientation and mobility and object identification.
The device uses a video camera mounted on a pair of sunglasses. It translates visual data into patterns on a "tongue array" -- a postage-stamp sized plate attached to the glasses via a cable.
The array is a grid of 400 electrodes that pulse to create images that change as the camera moves. Neuroimaging research suggests that using BrainPort stimulates the visual regions of the brain in persons who are blind.
While BrainPort does not replace vision, it provides a new sensory language. It enhances the overall sensory experience and gives users information on the size, shape, and location of objects in their environment -- perception that can help blind persons move with greater independence.
How the BrainPort Vision Device Works:
The BrainPort V100 vision device consists of a base unit, a digital video camera, and a postage-stamp-sized (3 cm by 3 cm) electrode array -- worn in the mouth like a retainer -- placed on the top surface of the tongue.
The video camera collects visual information in the form of white, black, and gray pixels. A processor in the base unit translates the data into patterns of gentle electrical impulses that it sends to electrode array on the tongue.
Strong vibrations represent white pixels, medium-strength represent gray, and no vibrations represent black pixels. Newer models have 400 to 600 electrodes and deliver data at approximately 30 frames per second for an information-rich image stream.
Neuroscientist Dr. Paul Bach-y-Rita pioneered the concept of "sensory substitution," BrainPort's underlying principal, in the late 1960s.
Since it is the brain, and not the eye, that processes vision, Bach-y-Rita proposed that visual perception (i.e. the electrical impulses the brain interprets) could be delivered through a secondary sense such as touch.
BrainPort sends electrical impulses to the brain through nerves in the tongue rather than the optic nerve.
BrainPort Training & Use:
Learning to read the patterns the BrainPort creates is similar to reading the raised dots of braille. The tongue array is similar to a refreshable braille display.
Just as braille dots feel like random bumps to new users, relating electrical impulses to objects in one's world takes time and specialized training.
Those interested in using the BrainPort device must complete a minimum of 10 hours of supervised training usually held over a two-week period.
The training focuses on proper interpretation of sensory data and operation of the device's controls. Training requirements and content are customized to the individual user.
Participants in recent studies using BrainPort tongue array prototypes with 100 - 600 electrodes have recognized the location and movement of high-contrast objects and some aspects of perspective and depth.
Ten hours of training often enables users to achieve the following milestones:
- Within minutes: users perceive where in space stimulation arises (up, down, left, and right) and the direction of movement
- Within an hour: users can identify and reach for nearby objects and point to and estimate the distance of objects out of reach
- Within several hours: users can identify letters and numbers and can recognize landmark information.
Blind Mountaineer Erik Weihenmayer Describes Using BrainPort:
In October 2009, Weihenmayer described using BrainPort to students at the Lyme School in New Hampshire. "They tingle," said Weihenmayer. "Certain combinations of dots turn on to form lines, shapes. I'm looking at a 3D world and it's translating it into a picture I'm feeling with my tongue."
Weihenmayer showed a video of him using BrainPort to play tic-tac-toe with his daughter.
At present, BrainPort is an "investigational prototype" and not commercially available in the United States.