If you don’t think the act of stacking and shuffling a set of cups could boggle your mind, watch the video below. In it, neuroscientist David Eagleman introduces 10-year-old Austin Naber – a world record-holding, champion cup stacker. Naber moves the cups around at a blistering pace and when Eagleman has a go at keeping up with him, the difference in skill and speed becomes immediately apparent.

“He smoked me,” Eagleman admits. “But the bigger point is that when I’m doing it, it’s my first time cup stacking. It’s all conscious for me, I’m burning a lot of energy trying to figure out the rules; how the cups balance.”

Both Eagleman and Naber had their brain activity monitored via an electroencephalogram (EEG). The difference was stark. Eagleman’s brain was firing on all cylinders, but Naber’s barely flinched – despite the pace at which he was moving.

“His brain was much more serene than mine because he had automised his behaviour,” explains Eagleman. Hours a day of practice had internalised the behaviour of cup stacking for Naber, making it far less mentally taxing. What other things can our brains get up to without conscious intervention?

The reason you practise sports over and over again is so you get really good at automising your action – David Eagleman

It’s a question that Eagleman explored in a PBS television series that aired recently on BBC4 in the UK. The non-conscious mind, he says, plays a much deeper role in our everyday decisions and relationships than we might realise.

You’re already aware of the fact that breathing and organ functions are things we do “automatically”, but there are lots of other examples.

Take the experience of hitting a ball with a bat. It takes a ball travelling close to 100mph (160km/h) just a few hundred milliseconds to reach the hitter. It’s so fast that it’s not possible to consciously register the trajectory of the ball and one’s response to it. It’s only after hitting the ball, indeed, that we truly register what happened consciously.

“The reason you practise sports over and over again is so you get really good at automising your actions,” says Eagleman. “Thinking about them, naturally, slows you down.”

The non-conscious mind also plays a role in more sophisticated actions, whether it’s deciding on attraction to the opposite sex, completing mathematical sums or forming political views. There are even strange cases where people who are ostensibly blind can ‘see’, thanks to the non-conscious part of their minds: a phenomenon known as blindsight.

“There is debate in the field about whether consciousness even has efficacy,” says Eagleman. “By the time your conscious mind registers something, is it always just the last guy to get the news, and it doesn’t even matter what it thinks?”

Indeed, designers and advertisers have known how to control our non-conscious decisions for centuries. By using subtle cues designed to bypass conscious awareness, they can “trick” us so that we drive more safely, navigate cities in ways we do not realise and even drink more alcohol at the bar.

Yet now that neuroscientists are exploring the influence of our non-conscious actions, they may also be able to suggest ways to improve our lives. For example, one question that Eagleman is exploring in his current research is the extent to which the conscious versus the non-conscious mind plays a role in addictions to drugs like cocaine. It’s early unpublished research, but the hope is that by training addicts to be more consciously aware of their cravings, they might gain better control over them.

Our conscious minds are really just a summary of what our brains get up to all the time

The more we probe the brain’s workings, the more we realise that our conscious minds are really just a summary of what our brains get up to all the time – without “us” having any idea. As Eagleman puts it, “The conscious you, which is the part that flickers to life when you wake up in the morning, is the smallest bit of what’s happening in your head.

“It’s like a broom closet in the mansion of the brain.”

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