This day 30 years ago signaled the birth of the World Wide Web, ushering in the information age and revolutionizing life as we know it.

“Vague but exciting.”

This was how Sir Tim Berners-Lee’s boss responded when the 33-year-old British physicist submitted his proposal for a decentralized system of information management on March 12, 1989.

Today there are over 4.4 billion internet users worldwide, growing at a rate of more than 11 new users per second. Internet user growth has accelerated in the past year, with more than 366 million new users coming online since January 2018.

This is your brain on the internet

The Internet takes advantage of the two most important features within the human brain – that social behaviour elicits pleasure and that vision triggers memories and emotions deep within our unconscious minds.

The first feature is that social activity triggers a nerve pathway deep in our subconscious – the mesolimbic dopamine pathway – also called the reward pathway, releasing a chemical called dopamine which bathes the brain’s pleasure centres – similar to other activities with intrinsic value such as food, sex and getting money.

Getting high on social activity

People like talking about themselves on social media because it has intrinsic value by generating a warm emotion of being part of something important. In other words, we like sharing because it is enjoyable for its own sake as a social activity. In this way sharing is deeply sensory – we humans literally ‘get high’ on social activity.

The image to the left is a view of the human brain cut down the middle. The reward pathway – shown in red – is activated by a rewarding stimulus.

The major structures in the reward pathway are highlighted: the ventral tegmental area (VTA), the nucleus accumbens and the prefrontal cortex.

The VTA sends information along its connections to both the nucleus accumbens and the prefrontal cortex. The neurons of the VTA contain the neurotransmitter dopamine which is released in the nucleus accumbens and in the prefrontal cortex. The pathway shown here is not the only pathway activated by rewards, other structures are involved too, but only this part of the pathway is shown for simplicity

The power of online images

The second feature worth noting is that over 70% of the human brain is dedicated to vision which means that our brains think in terms of visual images.

In fact, the visual system is the first to mature in the human brain so that by the age of five, children are able to compete on visual games with their grandparents …and win!

This explains why social networks like Instagram that use images are so popular.

The internet and the brain share common features

Ed Bullmore, professor of psychiatry at the University of Cambridge, has noted how the human brain and the internet have quite a lot in common.

“They are both highly non-random networks with a “small world” architecture, meaning that there is both dense clustering of connections between neighbouring nodes and enough long-range short cuts to facilitate communication between distant nodes, ” he points out.

Both the internet and the brain have a wiring diagram dominated by a relatively few, very highly connected nodes or hubs; and both can be subdivided into a number of functionally specialised families or modules of nodes. – Ed Bullmore

Berner Lee’s thoughts on the world wide web today

While the invention of the world wide web has changed our world in many positive ways, there is a dark side that has recently emerged.

In an open letter to mark the anniversary, Berner Lee questioned what it has become on the 30th anniversary of its creation, noting democracy and privacy were now under serious threat.

But he added it wasn’t too late to straighten the ship’s course.

“If we give up on building a better web now, then the web will not have failed us. We will have failed the web,” he wrote. “It’s our journey from digital adolescence to a more mature, responsible and inclusive future.”

We could equally apply these words to the neurobiology of internet usage. Whether the internet is changing our minds for the better or not is a debate that coalesced around Nicholas Carr’s book published a decade ago The Shallows: What the Internet Is Doing to Our Brains).  Carr argues that the internet is making us “more stupid” as we are losing the ability to concentrate and remember.

Perhaps the question is less about how the internet is changing our brains, but more accurately how is it changing our thinking.

But that’s a debate for another day.

Since we’re not going to dismantle the world wide web any time soon, the most important question is: how should we respond?