It’s likely you just assume you see 3D information the same as most people.  However, the latest NeuroTracker study by Professor Faubert at the Faubert Lab reveals this may not be the case.  The way we see the 3D world around us can vary greatly from one person to another. Here we’ll take a look at why.

What is 3D?

Perceiving 3D information is not as straight-forward as it sounds.  For example, our brains visually interpret flat images such as photos or on movie screens to be convincing 3D.  This is because all sorts of cues such as perspective, colours, tonal shades, and context are used to make sense of the positions of everything we see.

However, a powerful system for perceiving the distance and structure of objects is what’s called ‘stereopsis’ (or ‘stereoscopic depth perception’).  This makes use of ‘binocular vision’ - seeing with two eyes.

In a nutshell, stereopsis involves your brain using the different viewing angles of each eye to calculate depth with high precision.  This stereo vision processing uses higher order brain functions.

Dynamic Scenes

Stereopsis for perceiving static objects is pretty well understood.  However when it comes to perceiving one or more things moving quickly across a wide field of view things, less so.  Things get a lot more complex, especially as stereo vision isn’t just used for what you focus on – it’s also used for peripheral vision.  For this reason its an active area of research for vision scientists.

It’s also an important topic. When you are processing dynamic scenes, stereo vision provides a critical edge. We rely on this form of 3D perception in everyday situations such a driving in traffic, navigating through a busy street, or playing sports.  Just try something as simple as catching a ball one-handed with one eye closed, and you’ll realize how useful it is.

Isolating Stereo Vision With NeuroTracker

Professor Faubert wanted to investigate how much we use stereopsis to process dynamic scenes and to see if this varies across different populations.  To do this he tested three groups on NeuroTracker: healthy children, adults, and older people.

Each person performed a baseline both in stereo (with Active 3D & glasses), and in non-stereo (without Active 3D or glasses).The differences in baselines isolated exactly how much advantage each person got from performing NeuroTracker with stereo vision.

What Was Found

In all of the groups stereo vision allowed people to perform better at NeuroTracker.

For adults the advantage was large, then not quite as large for children, whose brains are still developing stereo vision capacities.  However, for elderly people, it was greatly reduced.  In fact, adults had an approximately four times larger advantage than elderly people when donning Active 3D glasses.

What The Results Mean

The findings suggest that higher order brain processes used for perceiving dynamic stereoscopic information are strongly affected by the normal aging process.  In terms of how this could affect everyday life, two separate studies (1 & 2) showed that lower NeuroTracker baselines (with Active 3D) related significantly to the increased risk of accidents when driving.

Interestingly, a separate study by Professor Faubert showed that although older people initially perform NeuroTracker at lower levels than young adults, they have equally good learning capacities.  This showed that their neuroplasticity is still very much active, allowing them to achieve the levels of young adults with just a few hours of distributed training.  It has also been found that such NeuroTracker gains in older populations transfer to improved abilities to process human movement.

From this perspective, NeuroTracker could be used to identify weaknesses in stereo vision, and then potentially improve them with training. Professor Faubert underlined the importance of learning capacity and transfer to real-world needs.

“You can see your ability to improve on this task just get better and better and better.  This improvement in ability that we see clearly on the NeuroTracker score relates to real function.  Whether it be attention measures, brain function, abilities in the field when it comes to sports, anticipating… movements to avoid collisions.  It’s getting your brain more efficient at what it does.”

You can read a related blog on stereo vision here.

How the Brain Processes Our 3D Environment

NeuroTracker Studies

Effect of age and stereopsis on a multiple-object tracking task

Three-Dimensional Multiple Object Tracking Speed Thresholds are Associated with Measures of Simulated Driving Performance in Older Drivers

Driving simulator scenarios and measures to faithfully evaluate risky driving behavior: A comparative study of different driver age groups

Healthy older observers show equivalent perceptual-cognitive training benefits to young adults for multiple object tracking

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