Purchase this article with an account.
Amir Amedi, Daniel-Robert Chebat, Shelly Levy-Tzedek, Galit Buchs, Shachar Maidenbaum; Returning Sensory Substitution to practical visual rehabilitation. Invest. Ophthalmol. Vis. Sci. 2014;55(13):4146.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Sensory substitution devices (SSDs) have come a long way since first developed for visual rehabilitation, producing exciting experimental results, and furthering our understanding of the human brain. Unfortunately, they are still not in wide use for practical visual rehabilitation, and are considered as reserved mainlyy for experiments in controlled settings. Why haven’t they been adopted? This is usually blaimed on a combination of practical problems such as the length and complexity of training, unpleasantness of stimuli, cost, weight etc. on the one hand, while on the other biological glass-ceiling reasons such as missed critical periods and plastic reassignment of visual regions were a cause for pessimism. Over the past years, both of these categories underwent significant changes. Our understanding of the neural mechanisms behind visual restoration has changed as a result of converging evidence, much of which was gathered with SSDs. This evidence suggests that the brain is more than a pure sensory-machine but rather is a highly flexible task-machine, i.e., brain regions can maintain or regain their function in vision even with input from other senses, offering a neurobiological basis for the use of SSDs. In parrallel, new technological opportunities have arisen for creating new SSDs and improving existing ones. Here we utilized these new technologies and this new understanding of brain organization back into practical visual rehabilitation, and test SSDs under various practical behavioral tasks.
In this work we used several SSDs - the veteran vOICe SSD, the new EyeCane SSD, which conveys single-point depth, and the EyeMusic SSD, which conveys whole-scene shape and color information - in a series of practical behavioral tests.
We show that while still far from vision, results were far above the expected by previous pessimistic views of SSDs. Users succeeded in a series of tasks in real-world settings such as correctly reaching for objects, recognizing real facial expressions and navigating through obstacle courses and unknown environments.
These new results, combined with the understanding of the brain as a task machine and other recent behavioral achievements strongly suggest that the time has come to revive the focus on practical visual rehabilitation with SSDs and we will chart several key steps we believe are necessary in this direction such as training protocols and self-train tools.
This PDF is available to Subscribers Only