For more than a decade, researchers have been trying to figure out how they can cure blindness with a bionic eye - or what scientists like to call a prosthetic retina.
And they have come a long way. Bionic vision technology has already been able to restore some visual perception in patients who are otherwise rendered completely blind from diseases like macular degeneration or retinitis pigmentosa.
Blindness due to retinal degeneration is a profound challenge, not to mention a hefty public health burden.
Approximately 1 in 12 Australian adults will experience macular degeneration in their lives, and - to date - bionic devices have shown by far the greatest promise of any treatment option in being able to help these individuals to fully experience the world once again.
While the research remains in its infancy, it is likely to keep improving to the stage where a meaningful form of sight is restored for these patients in the not-too-distant future.
But what are the ethical implications of an electronic prosthesis replacing natural vision?
What happens if the technology goes wrong and patients' visual perception is distorted or altogether misleading? And who is responsible for high-impact decisions made under such a false pretence?
The bionic eye
Retinal prostheses work by electrically stimulating the retina, essentially doing the job of the photoreceptors that are killed off by retinal diseases.
The "sight" they currently provide is heavily limited. People with bionic eyes usually see small, grey-scale flashes of light in their central vision that loosely correlate to the presence of objects.
This in itself is a remarkable achievement of neuroscience, but there is still a lot of work to do. Even with a bionic eye, patients remain debilitated by their lack of sight. They still cannot distinguish between faces, numbers, read fine text, or make high order decisions autonomously.
But Dr Matthew Petoe from the Bionics Institute in Melbourne is hopeful for the future. Thanks to advances in bionic eye technology, he says patients may soon be able to navigate without the use of a guide dog, and they may even be able recognise distinct facial expressions.
Exactly how researchers can achieve these sorts of outcomes remains unclear, but Dr. Petoe is certain bionic vision will continue to improve at a rapid pace.
The ethical implications
It's obvious a more functional bionic eye will drastically improve lives and lead to greater autonomy for patients, but there is a hidden cost. Given the limited number of clinical trials done for this technology, it's difficult to say how open to misinterpretation a patient's perception may be with a bionic eye.
The inability of patients to distinguish between numbers and read fine text means when they misinterpret something, it could result in material losses beyond their control. For example, this could happen if patients misread a number or figure when managing their finances.
When you start to think about it, there are a whole bunch of potentially dangerous scenarios that could arise from faulty sight.
For instance, misinterpreting facial expressions may skew a person's judgement in a social context, and misreading crucial information like street signs could put patients in harm's way. In these cases, patients will have no way of knowing how realistic their prosthetically-induced perception actually is.
And therein lies the problem. The future of bionic vision represents a potential infringement upon individual autonomy to an unknown degree.
It isn't good enough to offer an improvement to a diseased person's quality of life if that improvement goes hand in hand with a newly imposed risk of suffering.
One of the difficulties in making bionic vision more naturalistic is the wide range of diseases that warrant a bionic eye, as well as the number of differences in psychophysical responses to a given stimulus. That is to say, different people respond differently to the same thing.
As a result, it is likely the risk of misinterpretation and perceptual distortion won't be the same for everyone.
Balancing the benefits and risks
Cellular gene therapy is an alternative approach that could solve some of these issues. Because it is tailored to the individual, the technology could reduce the inherent ethical complications associated with the bionic eye.
But even though he acknowledges the successes of gene therapy, Professor Michael Ibbotson, director of the National Vision Research Institute says, "it is unlikely to solve all neurological issues. There is very likely to be a need for bionics."
As such, it is incumbent upon the neuroscientists and biomedical engineers tasked with the development of an Australian-made bionic eye, to consider their ethical responsibilities. As with any new technology, there is a risk that it will be used malevolently and to influence the behaviour of vulnerable populations.
The ethical future of bionic vision is somewhat cloudy, but Professor Ibbotson and others at the Bionics Institute, who have been strong proponents for the advancement of bionic vision in Australia, maintain there is an ethically justifiable balance of benefit and risk.
A healthy dose of skepticism surrounds the development of brain interface technology, as it becomes a more common research topic. These devices, which include prosthetic limbs, have the potential to greatly assist disabled people.
Developing and making accessible a bionic eye absent of any serious ethical violations would greatly enhance public acceptance and enthusiasm towards the development of bionics.
All in all, the bionic eye could do wonders for people in need.