UW Eye Research Institute
Top: Using the BrainPort vision device, blind subject Eric Weihenmayer can “see” his daughter’s drawing of their cat. Bottom: The base unit screen allows the trainer to see the digital camera image as well as the
portion of the cat’s head that Eric perceives.“The system consists of a high resolution tongue display, a control box, and a digital video camera. Visual information collected from a head-mounted camera is translated into an electrical pattern that is ‘drawn’ or mapped on the tongue,” explains Arnoldussen. In the current prototype, the inch-square, 25 x 25 electrode array that rests on the tongue includes over 600 contact sensors. Via tingling electrical pulses, experienced by users as soda bubbles or champagne effervescence, these sensations are transmitted from tongue to brain and the subject “sees” due to the brain’s ability to analyze and interpret the stimuli as visual information.
Interpretation of this unusual input requires training and practice, like learning any new language, and Arnoldussen is an able and enthusiastic teacher. She has used the vision device herself, believing it essential to know what it feels like and to discern how the body is cued and how it responds to stimuli. “My teaching focuses on facilitating user interactions and helping them match their multisensory experiences with the patterns registering on their tongues.” Users must learn to move their heads around to survey images, objects, and surroundings—just as sighted people move their eyes. Arnoldussen structures the training to encourage users to first identify what they know, putting contextual knowledge to work in deducing an object’s identity or spatial orientation—such as recognizing that the vertical lines under a chair are likely its legs.
By building exercises around perceiving directional orientation and shape of objects, discerning letters and shapes of various sizes, following black-line pathways delineated on a warehouse floor, and recognizing standing and suspended barriers in an obstacle course, Arnoldussen has led over twenty blind subjects to remarkable levels of success. (Next)(Previous)