Curious Kids: if our eyes see upside down, how does the brain flip the picture?

Daniel Joyce, University of Southern Queensland

I heard that we see upside down, but our brain flips the image. How does it do that?

–Jasmine, Mount Evelyn, Victoria

Our eyes work thanks to light. Objects we can see are either sources of light themselves – like a candle or a phone screen – or light bounces off them and makes its way to our eyes.

First, light passes through the optical components of the eyes such as the cornea, pupil and lens.

Together, they help focus the light onto the retina that senses light, while also controlling the intensity of light to help us see well while avoiding damage to the eye.

The function of the lens is to correctly focus light that comes from objects at different distances. This process is known as accommodation.

While performing this important task, light passing through the lens becomes inverted. This means that light from the top of the object falls lower on the retina than light from the bottom, which falls higher on the retina.

So, light exiting the lens to land on the retina is indeed flipped upside down. But that doesn’t mean the brain is actually flipping the picture “back”. Here’s why.

The orientation doesn’t actually matter

While the light being interpreted by the brain is “upside down” compared to the real world, the question is: is that actually a problem for us?

From your own experience you can tell the answer is probably no. We seem to navigate and interact with the world just fine.

So, where in the brain is the image flipped or rotated 180 degrees to be the “right way up” again?

You may be surprised to learn that vision scientists reject the idea a flipping or rotation needs to happen at all. This is because of how our brains process visual information.

The object you perceive is “encoded” by the firing of various neurons – brain cells that process information – in various locations in the brain. This pattern of firing is what encodes the information about the object you’re focusing on. That info takes into account the object’s relation to everything else in the scene, your body in the world, and your movements.

As long as the relative encodings of these are all consistent with one another, as well as stable, there’s no need for a flip to happen at all.

We can function with ‘upside down’ goggles!

Several studies have looked at how we adapt to large changes in visual input by asking people to wear goggles that flip the image coming in.

This means the image lands on the retina the “right way up”, so to speak, but upside down from what the brain has learned it should be.

In the 1930s, two scientists in Austria performed the Innsbruck Goggle Experiments. For weeks or even months at a time, participants in these studies wore goggles that altered the way the world around them looked. This included goggles that turn the incoming image upside down.

 
A person blinks while wearing an ‘invertoscope’ – goggles that turn the incoming image upside down. Dmitry Hoh/Wikimedia Commons, CC BY-SA

As you can imagine, people wearing these goggles at first found it really difficult to get by in their day-to-day activities. They would stumble and bump into things.

But this was temporary.

Participants reported seeing the world upside-down for the first few days, with difficulties navigating the environment, including trying to step over ceiling lights that appeared to them as on the floor.

Around the fifth day, however, performance seemed to improve. Things that were at first seen upside down now appeared the right way up, and this tended to improve with more time.

In other words, with continued exposure to the upside-down world, the brain adapted to the changed input.

More recent studies are beginning to identify which areas of the brain are involved in being able to adapt to changes in visual input, and what the limits of our ability to adapt might be.

Adaptation may even allow “colour blind” people to see colour better than is predicted from their condition.The Conversation

Daniel Joyce, Senior Lecturer in Psychology, University of Southern Queensland

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Why your brain has to work harder in an open-plan office than private offices: study

Since the pandemic, offices around the world have quietly shrunk. Many organisations don’t need as much floor space or as many desks, given many staff now do a mix of hybrid work from home and the office.

But on days when more staff are required to be in, office spaces can feel noticeably busier and noisier. Despite so much focus on getting workers back into offices, there has been far less focus on the impacts of returning to open-plan workspaces.

Now, more research confirms what many suspected: our brains have to work harder in open-plan spaces than in private offices.

What the latest study tested

In a recently published study, researchers at a Spanish university fitted 26 people, aged in their mid-20s to mid-60s, with wireless electroencephalogram (EEG) headsets. EEG testing can measure how hard the brain is working by tracking electrical activity through sensors on the scalp.

Participants completed simulated office tasks, such as monitoring notifications, reading and responding to emails, and memorising and recalling lists of words.

Each participant was monitored while completing the tasks in two different settings: an open-plan workspace with colleagues nearby, and a small enclosed work “pod” with clear glazed panels on one side.

The researchers focused on the frontal regions of the brain, responsible for attention, concentration, and filtering out distractions. They measured different types of brain waves.

As neuroscientist Susan Hillier explains in more detail, different brain waves reveal distinct mental states:

  • “gamma” is linked with states or tasks that require more focused concentration
  • “beta” is linked with higher anxiety and more active states, with attention often directed externally
  • “alpha” is linked with being very relaxed, and passive attention (such as listening quietly but not engaging)
  • “theta” is linked with deep relaxation and inward focus
  • and “delta” is linked with deep sleep.

The Spanish study found that the same tasks done inside the enclosed pod vs the open-plan workspace produced completely opposite patterns.

It takes effort to filter out distractions

In the work pod, the study found beta waves – associated with active mental processing – dropped significantly over the experiment, as did alpha waves linked to passive attention and overall activity in the frontal brain regions.

This meant people’s brains needed progressively less effort to sustain the same work.

The open-plan office testing showed the reverse.

Gamma waves, linked to complex mental processing, climbed steadily. Theta waves, which track both working memory and mental fatigue, increased. Two key measures also rose significantly: arousal (how alert and activated the brain is) and engagement (how much mental effort is being applied).

In other words, in the open-plan office participants’ brains had to work harder to maintain performance.

Even when we try to ignore distractions, our brain has to expend mental effort to filter them out.

In contrast, the pod eliminated most background noise and visual disruptions, allowing participant’s brains to work more efficiently.

Researchers also found much wider variability in the open office. Some people’s brain activity increased dramatically, while others showed modest changes. This suggests individual differences in how distracting we find open-plan spaces.

With only 26 participants, this was a relatively small study. But its findings echo a significant body of research from the past decade.

What past research has shown

In our 2021 study, my colleagues and I found a significant causal relationship between open-plan office noise and physiological stress. Studying 43 participants in controlled conditions – using heart rate, skin conductivity and AI facial emotion recognition – we found negative mood in open plan offices increased by 25% and physiological stress by 34%.

Another study showed background conversations and noisy environments can degrade cognitive task performance and increase distraction for workers.

And a 2013 analysis of more than 42,000 office workers in the United States, Finland, Canada and Australia found those in open-plan offices were less satisfied with their work environment than those in private offices. This was largely due to increased, uncontrollable noise and lack of privacy.

Just as we now recognise poorly designed chairs cause physical strain, years of research has shown how workspace design can result in cognitive strain.

What to do about it

The ability to focus and concentrate without interruption and distraction is a fundamental requirement for modern knowledge work.

Yet the value of uninterrupted work continues to be undervalued in workplace design.

Creating zones where workers can match their workplace environment to the task is essential.

Responding to having more staff doing hybrid work post-pandemic, LinkedIn redesigned its flagship San Francisco office. LinkedIn halved the number of workstations in open plan areas, instead experimenting with 75 types of work settings, including work areas for quiet focus.

For organisations looking to look after their workers’ brains, there are practical measures to consider. These include setting up different work zones, acoustic treatments and sound-masking technologies, and thoughtfully placed partitions to reduce visual and auditory distractions.

While adding those extra features in may cost more upfront than an open plan office, they can be worth it. Research has shown the significant hidden toll of poor office design on productivity, health and employee retention.

Providing workers with more choice in how much they’re exposed to noise and other interruptions is not a luxury. To get more done, with less strain on our brains, better design at work should be seen as a necessity.The Conversation

Libby (Elizabeth) Sander, MBA Director & Associate Professor of Organisational Behaviour, Bond Business School, Bond University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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