What Does CVI Look Like?
If you have typical vision, how does CVI look different to that?
One way to show what CVI looks like is through a simulation, where the altered visual world can be seen in terms of how it is different from the typical visual world.
There are lots of simulations to show what different visual impairments look like, including visual field loss, reduced visual acuity and reduced contrast sensitivity, for example SIGHT-SIM (all links at the end of the page).
What about the CVIs that are known as dorsal stream dysfunction, higher visual processing difficulties or visual perception difficulties - what do they look like?
That is a lot more tricky to show.
Because those visual impairment do not relate to the picture created, but to visual attention.
This is what we are trying to show through a project called CVI-SIM, with the University of St Andrews.
CVI-SIM picks up on work we started a few years ago, where we showed adults with diagnosed dorsal stream dysfunction short videos and asked them to tell us what they saw, recording the sessions. What emerged was a window of visual attention within their visual field that was very dynamic, as we showed and explained in our Dorsal Stream Dysfunction CVI Experience video.
CVI-SIM uses virtual reality to attempt to show these described experiences, through a specially designed programme with multiple controls and options, and many different classrooms, both mainstream, and special schools, cluttered and uncluttered.
How do we know it is accurate?
None of us can experience life as another person. Vision, even without CVI, is extremely dynamic, as are all brain processes, so nothing will ever be 100%. We have an expert consultation team, supported by a primary validation team of people directly affected by dorsal stream dysfunction with clear medical diagnosis, as detailed on our CVI SIM Virtual Reality Progress Video page. But this is not enough.
This work needs further research. For this reason, currently we are only able to share videos of the work in progress.
In the future we aim to offer the CVI-SIM programme for free, for you to download onto a computer. Using your mouse and control keys, with multiple individual settings options, we want to give you the opportunity to learn more about the world of the person with CVI you support, by giving you a real insight into what it might look like, from what has been described. If you are lucky enough to have access to a Virtual Reality headset, then you could have an incredibly immersive experience of CVI.
As far as we are aware, this is the first time anyone has attempted to show these altered visual experiences, and it has taken an enormous amount of work, but why have we done it?
You can't learn visually from something you can't see.
There is confusion about what a child with CVI can and cannot see. All too often we hear of children with CVI receiving support for a learning disability, or social / behavioural challenges, and not a visual impairment. Understanding the child's visual impairment is absolutely central to targeting support. This was explained in Gordon Dutton's Blog 32 - Making Things Accessible.
Our hope is that if we are able to show what this type of CVI looks like, and what is not visible, then those responsible for support can make the changes needed to help the child learn.
Please take a few minutes to view some of the progress videos below. They introduce what the world may well look like as it has been described to us by people with CVI.
Is it what you imagined?
There is a lot more to come, we will keep you posted as CVI-SIM develops.
One more thing...do you have CVI or support someone with CVI? Maybe you are a parent? We would love to hear what you think about these videos. Please tell us, it is your world or the world of the person you support we are trying to show - your experiences and views matter; you are our experts. We would love to learn from you, including if you don't feel we are getting it right. Tell us why, then we can make it better. Email us at: email@example.com
The CVI Scotland Team
PS Everything new can be found in our Updates section, and via Twitter @scotlandcvi and our Facebook page.
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