Clinical Tests of Ultra-Low Vision Used to Evaluate Rudimentary Visual Perceptions Enabled by the BrainPort Vision Device
Level 4 - case-series / case-control
Pre-post interventional pilot study / case series without a control group
OpenAlex W1965099908 · doi:10.1167/tvst.2.3.1
What was done
Three female participants with healthy ocular status (average age 43) completed 11 computer-based psychophysical tests across three batteries (Basic Assessment of Light Motion, Basic Assessment of Grating Acuity, and the Freiburg Vision Test) alongside a modified Tangent Screen. Testing was conducted at baseline and repeated using the BrainPort electrotactile tongue display system following 15 hours of device training.
What was found
Mean success scores increased for all tests except contrast sensitivity. Statistically significant increases occurred in tests of light perception (8.27 ± 3.95 SE), time resolution (61.4% ± 3.14 SE), light localization (44.57% ± 3.58 SE), grating orientation (70.27% ± 4.64 SE), and white Tumbling E on a black background (2.49 logMAR ± 0.39 SE). Motion tests were limited by device resolution.
Why it matters
The findings indicate that standardized psychophysical testing batteries designed for ultra-low vision can be applied to sensory substitution devices. This supports developing standardized outcome measures for artificial vision technologies.
Limits
The sample size is minimal (n = 3) and evaluated only healthy, normally sighted individuals rather than visually impaired individuals. There was no separate control group to rule out test-retest learning effects, and hardware resolution constrained motion assessments.
Cited by
- supports The BrainPort device transmits visual information from a camera to an electrical grid on the tongue, enabling blind people to perceive shapes and navigate obstacle courses.