Square eyes and a fried brain, or a secret cognitive enhancer- how do video games affect our brain?

Shireene Kalbassi | 3 SEP 2018

If, like me, you spent your childhood surrounded by Gameboys and computer games, you have probably heard warnings from your parents that your eyes will turn square, and that your brain will turn to mush. While we can safely say that we are not suffering from an epidemic of square-eyed youths, it is less clear what gaming is doing to our brain.

In the support of worried parents all around the world, there is a disorder associated with gaming. Internet gaming disorder is defined as being an addictive behaviour, characterised by an uncontrollable urge to play video games. In 2013, internet gaming disorder was added to the Diagnostic and Statistical Manual of Mental Disorders (DSM), with a footnote, saying that more research on the matter is needed (American Psychiatric Association, 2013). Similarly, in 2018, the world health organisation (WHO) included internet gaming disorder to the section ‘disorders due to addictive behaviours’ (World Health Organization, 2018).

There is evidence to suggest that internet gaming does lead to changes in brain regions associated with addiction. Structurally, it has been shown that individuals diagnosed with internet gaming disorder show an increase in the size of a brain region known as the striatum, a region associated with pleasure, motivation, and drug addiction (Cai et al 2016, Robbins et al 2002). The brains of those with internet gaming disorder also show altered responses to stimuli related to gaming. In one study, two groups of participants were assessed: one with internet gaming addiction, and the other without. All the participants with internet gaming disorder were addicted to the popular multiplayer online role-playing game, World of Warcraft. The participants were shown a mixture of visual cues, some being associated with World of Warcraft, and others being neutral. Whilst being shown the visual cues, the brains of the participants were scanned for brain activation using an fMRI machine. It was observed that when being shown visual cues relating to gaming, the participants with internet gaming disorder showed increased activation of brain regions associated with drug addiction, including the striatum and the prefrontal cortex.  The activation of these brain regions was positively correlated with self-reported ‘craving’ for these games; the higher the craving for the game, the higher the levels of activation (Ko et al 2009). These studies, among others, do suggest that gaming does have a place in joining the list of non-substance related addictive disorders.

But don’t uninstall your games yet; it is important to note that not everyone who plays computer games will become addicted. And what if there is a brighter side to gaming? What if all those hours of grinding away on World of Warcraft, thrashing your friends on Mario Kart, or chilling on Minecraft might actually benefit you in some way? There is a small, but growing, amount of research that suggests that gaming might be good for your brain.

What we have learnt about how the brain responds to the real world, is being applied to how the brain responds to the virtual world. In the famous work of Maguire et al (2000), it was demonstrated that the taxi drivers of London showed an increased volume of the hippocampus, a region associated with spatial navigation and awareness. This increased volume was attributed to the acquisition of a spatial representation of London. Following from this, some researchers asked how navigation through a virtual world may impact the hippocampus.

In one of these studies, the researchers investigated how playing Super Mario 64, a game in which you spend a large amount of time running and jumping around a virtual world (sometimes on a giant lizard) impacts the hippocampus. When compared to a group that did not train on Super Mario 64, the group that trained on Super Mario 64 for 2 months showed increased volumes of the hippocampus and the prefrontal cortex. As reduced volumes of the hippocampus and the prefrontal cortex are associated with disorders such as post-traumatic stress disorder, schizophrenia and neurodegenerative diseases, the researchers speculate that video game training may have a future in their treatment (Kühn et al 2014). In another study, the impact of training on Super Mario 64 on the hippocampus of older adults, who are particularly at risk of hippocampus-related pathology, was assessed. It was observed that the group that trained by playing Super Mario 64 for 6 months showed an increased hippocampal volume and improved memory performance compared to participants who did not train on Super Mario 64 (West et al 2017). So, it appears that navigating virtual worlds, as well as the real world, may lead to hippocampal volume increase and may have positive outcomes on cognition.


A screenshot of Super Mario 64. This game involves exploration of a virtual world. Image taken from Kühn et al 2014[1]

Maybe it makes sense that the world being explored doesn’t have to be real to have an effect on the hippocampus, and games like Super Mario 64 have plenty to offer in terms of world exploration and navigation. But what about the most notorious of games, those first-person shooter action games? It has been suggested that first-person shooter games can lead to increased aggressive behaviours in those who play them, however researchers do not agree that this effect exists (Markey et al 2014 Greitemeyer et al 2014). Nevertheless, can these action games also have more positive effects on the cognitive abilities of the brain? Unlike Super Mario 64, these games require the player to quickly respond to stimuli and rapidly switch between different weapons and devices to use, depending upon the given scenario. Some researchers have investigated how playing action games, such as Call of Duty, Red Dead Redemption, or Counterstrike, impact short-term memory. Participants who either did not play action games, causally played action games, or were experienced in playing action games were tested for visual attention capabilities. The participants were tested on numerous visual attention tests, involving recall and identification of cues that were flashed briefly on a screen. The researchers observed that those who played action games showed significantly better encoding of visual information to short-term memory, dependent on their gaming experience, compared to those who did not (Wilms et al 2013).

In another study, the impact of playing action games on working memory was assessed. Working memory is a cognitive system involved in the active processing of information, unlike short-term memory which involves the recall of information following a short delay (Baddeley et al 2003). In this study, the researchers tested groups of participants who either did not play action games or did play action games. The researchers tested the participants’ working memory by utilising a cognitive test known as the “n-back test”. This test involves watching a sequence of squares that are displayed on a screen in alternating positions. As the test progresses the participants have to remember the position of the squares on the screen from the previous trials whilst memorising the squares being shown to them at that moment.  The researchers observed that people who did play action games outperformed those who did not on this test; they were better able to remember the previous trials, whilst simultaneously memorising the current trials (Colzato et al 2013). From these studies, it appears that action games may have some benefit on the cognitive abilities of the players, leading to increased short-term processing of information in those who play them.

A screen grab from first person shooter games: Call of Duty: WW2 (left), and Halo (right). These fast-paced games involve quickly reacting to stimuli and making quick decisions to bypass enemies and progress in the game.

So, for the worried parents, and the individuals who enjoy indulging in video games, maybe it’s not all bad. As long as you are not suffering from a form of gaming addiction (and if you think you might be please see a health expert) maybe all these hours gaming may actually not be as bad for your brain as it might seem. But ultimately, much more research is needed to understand how a broader range of games played over childhood development, and for time periods of years and decades, affects our brains and mental health.

If you think you may be suffering from a gaming addiction, see the NHS page  for more information.

Edited by Lauren Revie & Monika śledziowska


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Can we solve problems in our sleep?

Sam Berry | 19 MAR 2018

Have you heard the song “Scrambled Eggs”? You know:

“Scrambled eggs. Oh my baby how I love your legs.”

No? Perhaps you would recognize the tune.

A young Paul McCartney woke up one morning with an amazing melody in his head. He sat at the piano by his bed and played it out, and he liked it so much he couldn’t quite believe it had come to him in a dream. The tune was there, but he just couldn’t find the right words to fit. For several months he tried, but he couldn’t get past “Scrambled Eggs” as a working title.

So how did the famous Beatle complete his masterpiece? He did some more sleeping. Another fateful day, he woke up and the song was there, fully formed with lyrics and the now famous title “Yesterday.”

“Yesterday, all my troubles seemed so far away.”

Recognise it now? A critically acclaimed worldwide hit had formed itself in his sleep. Boom. A chart smashing phenomenon.

—— —– —– —– —— ——

It may seem obvious, but not sleeping is extremely bad for you. Symptoms of sleep deprivation include a marked decline in the ability to concentrate, learn, and retain new information. It can affect your emotions, self-control, and cause visual and auditory hallucinations.

Whether not sleeping at all would actually kill you has not yet been established. The record time for someone staying awake is 11 days and 25 minutes during a science experiment in 1965. The subject was kept awake by two ‘friends’ as they observed him become a drooling delusional mess. Yet there are plenty of studies that demonstrate serious detrimental health effects of both short and long-term sleep deprivation.

Being mentally and physically alert will certainly help you to solve problems, but many scientists think something much more interesting is going on during sleep. Your brain is still learning whilst you are snoring.  

You are only coming through in waves…

Okay, so do we know how sleep can help us to learn? We’re getting there. Using brain imaging technology like fMRI scanners (giant magnets that use blood flow changes to see how different parts of the brain react to things) and EEG (funky hats with electrodes that measure how our neurons are firing in real time), we can have a look at what the brain is doing while we’re dozing off.

Our brains remain active while we sleep. Sleep can be split into different stages, and what happens during these stages is important for memory and learning. Broadly speaking, your sleep is split into non-REM (Stage 1, 2, and Slow Wave) and REM (Rapid Eye Movement) stages. These are traditionally separated depending on what the pattern of electrical output from the EEG is showing. I’ll briefly take you through what these different stages are and how our neuron activity changes as we go through them:

Stage One sleep is when we start to doze off and have our eyes closed. Have you ever noticed a grandparent falling asleep in their chair, but when you ask them to stop snoring they wake up insisting they were never asleep in the first place? That’s stage one sleep; you can be in it without even knowing.

Stage Two is still a light sleep, but when brain activity is viewed using EEG you can see an increase in spiking brain activity known as sleep spindles.

Slow Wave Sleep is so called because in this stage neurons across the brain activate together in unison, creating a slow, large coordinated electrical pattern. This makes the EEG output look like a wave. Slow wave sleep also contains some of Stage Two’s sleep spindles, and as well has something called sharp wave ripples. This is where a brain area called the Hippocampus (involved in memory and navigation) sends bursts of information to the Neocortex (involved in our senses, motor movement, language, and planning to name a few).

REM sleep is when our bodies are paralysed but our eyes dart around. Our blood pressure fluctuates and blood flow to the brain increases. While we dream throughout sleep, our dreams during REM become vivid and our brain activity looks similar to when we’re awake.

We cycle through these stages in 90 -120 minute intervals throughout the night, our sleep becoming deeper and more REM-based as the cycle progresses. Disruptions to the sleep cycle are associated with decreases in problem-solving ability as well as psychiatric and neurodegenerative disorders like Alzheimer’s.

Spikey learning

Problem solving requires memory: you need to use information you already have and apply it to the problem at hand. You also need to remember what you tried before so that you don’t keep making the same mistakes (like singing “Scrambled Eggs” over the same tune forever). The stages of sleep most relevant to helping us keep hold of our memories are the non-REM ones, and in particular Slow Wave Sleep.

Recent research reveals that sleep spindles, slow waves, and sharp wave ripples work together so when a slow wave is at its peak the brain cells are all excited, creating the perfect environment for the sleep spindles to activate. When the wave is crashing down, the sharp wave ripples from the Hippocampus are more likely to fire to the Neocortex. Recent research tells us this coupling of spindles and slow waves is associated with how well you retain memories overnight. Interestingly, in older adults spindles can fire prematurely before the wave reaches its peak, suggesting a possible reason why memory gets worse with age.

Researchers say this pattern of brain activity is a sign of the brain consolidating, or crystallising, what was learned or experienced whilst awake. This process strengthens the neural connections of the brain. Studies show that the pattern of neurons that get excited when we learn something are reactivated during sleep. This could mean that during sleep our brains replay experiences and strengthen newly formed connections.

Getting freaky

So what do our dreams mean? We’ve all had bizarre ones—how about that common dream where all your teeth fall out?

During REM sleep, our brain activity looks similar to when we’re awake. Scientist Deirdre Barrett suggested we think of REM sleep like merely a different kind of thinking. This type of thinking uses less input from the outside world or from the frontal parts of our brain in charge of logical thinking. REM is thought to be involved in consolidating our emotional memories, but it is also when we tend to have the vivid visual dreams that may defy logic. This combination enables REM “thinking” to be creative or even weird. REM sleep may allow us to form connections between ideas that are only distantly related.

Recently, a team in Germany suggested that Non-REM sleep helps put together what we know while REM breaks it up and puts it back together in new ways.

Thoughts before bed

So “sleeping on it” really can help solve problems. It strengthens the memories you make during the day and it helps learn and see things more clearly when you wake up. REM sleep may also allow thinking to be unconstrained by logic and divide and reshape ideas during REM. If reading this article made you sleepy, go ahead and take a nap. You might learn something.

Edited by Becca Loux. Becca is a guest editor for Brain Domain and an avid fan of science, technology, literature, art and sunshine–something she appreciates more than ever now living in Wales. She is studying data journalism and digital visualisation techniques and building a career in unbiased, direct journalism.


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