As the second decade of the 21st century draws to a close, we look at the big trends that emerged — and how they will continue to affect the way we live.

Barack Obama, you may recall, wore a BlackBerry on his hip back when this dying decade was young and shiny and brimming with hope. Very infrequently, he would thumb-type into the now-archaic device, tweeting to the world in 140-character doses.

Former U.S. President Barack Obama holds up his Blackberry after he ran back into the White House after forgetting the mobile phone while departing for a domestic trip November 21, 2014 in Washington, DC. Win McNamee

As much as he loved his Canadian-made phone, No-Drama Obama didn’t strike anyone as addicted to still-emerging digital platforms like Twitter. The decorous messaging was occasional, not random ranting 20 times a day.

But soon thereafter, Twitter and Facebook became entwined in real-world events, helping unleash the Arab Spring. Silicon Valley’s new digital tools weren’t the cause of the cascading pro-democracy uprisings that washed through the closed kleptocracies of the Middle East. But in the chorus of regime-jamming voices and images rising from the people’s phones, they showed themselves as transformational amplifiers.

What was going on? Lots on the ground. But a few things in our brains as well, though science is only now playing catch-up on the addiction taking hold in our heads.

Our collective craving for social media, cognitive neuroscientists have shown — and let’s put the whole of it into the decade-capping conversation: Instagram, YouTube, Pinterest, Snapchat, Tinder, Weibo, WhatsApp and TikTok, along with the shadier realms of Reddit, Telegram, 4chan and the darker web beyond — is actually a craving for the next splash of dopamine, a chemical produced by the brain that provides a feel-good reward for certain social stimuli, reinforcing our desire for more.

Some researchers liken the neurological process to that triggered by cocaine, albeit less intense. Some liken it to the anticipatory thrill one feels playing a slot machine — the moment between the level pull and the outcome, when dopamine neurons activate, creating a rewarding feeling even before the spinning stops.

Here’s how one Harvard Medical School neurobiology research technician describes the scope of the power in your pocket: “Smartphones have provided us with a virtually unlimited supply of social stimuli, positive and negative,” explained Trevor Haynes.

“Every notification, whether it’s a text message, a ‘like’ on Instagram or a Facebook notification, has the potential to be a positive social stimulus and dopamine influx.”

We all understood, to varying degrees, the quid pro quo: our data for dopamine. Facebook and Google alone now control three-quarters of Canada’s digital advertising dollars, thanks to algorithms that microtarget and monetize your movements, knowing what you intend to purchase the moment the impulse strikes. We let apps into our head to release dopamine; in exchange, the apps rummage around and gather up our every click — an average of 2,600 swipes a day on your device of choice, according to Harvard researcher Haynes.

This file photo taken on June 22, 2012 shows thousands of supporters of Muslim Brotherhood presidential candidate Mohamed Morsi packing Cairo's landmark Tahrir Square on June 22, 2012 to denounce a power grab by the ruling military, as the nation nervously awaited the results of the first post-Mubarak presidential election. MARWAN NAAMANI

How much any of us care is debatable — but also evolving. Does it really matter if the data miners see you cheering on the Arab Spring, Black Lives Matter or a meme involving unseated hockey talker Don Cherry? Because … puppies! Or that hilarious penguin video. Or news of your cousin’s new baby girl. That was the 2015 counterfactual.

Deeper into the decade, as our virtual joy ride grew ever more corrosive, hatred found a place alongside the hilarity and hope on your timeline — and into the mainstream.

So where are we now? And where is this beautiful beast taking us, as we turn the corner into the 2020s?

New Yorker staff writer Andrew Marantz published a book on our deeply broken information landscape, titled “Anti-Social: Online Extremists, Techno-Utopians, and the Hijacking of the American Conversation.”

Marantz frames social media giants as the New Gatekeepers and holds them responsible for leaving the gate to our minds ajar for the Gatecrashers — the conspiracists, white supremacists and nihilist trolls rising up from the rabbit holes of online radicalization, bending platforms to their corrosive will.

Marantz walks us through the pioneering clickbait of Upworthy and its many imitators, which in turn led to BuzzFeed, where virality was all that mattered, regardless of public interest. “The goal of the content was to elicit a response — a share, a like, a hate-read, an indignant comment. Any response was a form of engagement, and engagement was the lifeblood of the viral internet,” Marantz writes.

“High-arousal posts beat low-arousal posts; the fittest content proliferated, and everything else was driven toward extinction,” regardless of fact or fiction. The frenzy of it all — our bespoke, algorithm-driven walls of dubious, distractible content — don’t just chip away at the attention span in our haste to keep pace. They flatten over time, blurring the distinction between the real and the fake, the trivial and the consequential. Facebook is after your eyeballs, full stop, and holding their gaze as often and as long as possible.

Into this steamy mix, Marantz traces the rise — and subsequent isolation, post-Charlottesville — of some of the alt-right’s leading offenders. And his own struggles with the more notorious trolls of the realm.

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Reporters work in nearby phone booths during the House Intelligence Committee’s impeachment hearings, on Capitol Hill in Washington, Nov. 13, 2019. (Damon Winter/The New York Times) DAMON WINTER

“Trolls may be puerile, but they set an ingenious trap,” he writes. “By responding to their provocations, you risk amplifying their message. By ignoring them, you risk seeming complacent or complicit. … The opposite of normalization is outrage, but trolls use outrage as fuel. Trolls act in indescribably awful ways and then dare reporters to describe their actions dispassionately.

“But for reporters on the lurid ugliness beat,” he adds, “it’s often impossible to be even-handed and truthful at the same time.”

That such viral manipulation fell so seamlessly into the hands of the alt-right, Marantz concludes, leaves the American popular vocabulary in a period of deep dysfunction.

“At some point, the broken American vocabulary will be replaced by a new one. But whatever comes next will bear the scars of the current disruption. … The bigots are not destined to win. Nor are they destined to lose. The ending is not yet written.”

Canada, for its part, appears ready to embark on the tricky task of flexing regulatory muscle against hateful content. Prime Minister Justin Trudeau last month directed newly minted Heritage Minister Steven Guilbeault to create a new tranche of social media platform rules, “starting with a requirement that all platforms remove illegal content, including hate speech, within 24 hours or face significant penalties.” Trudeau said the new regulations must also include other online harms such as “radicalization, incitement to violence, exploitation of children or creation or destruction of terrorist propaganda.” Some form of data privacy protection also is expected as part of Ottawa’s bid to police the platforms.

Yet the brain-hackery of social media is taking on new shape elsewhere. Maya Wang, a senior China researcher at Human Rights Watch, warned this month of Beijing’s latest approach to undermining protesters in Hong Kong and among the imprisoned Turkic Muslims of western China — “reality engineering,” involving interrogation of detainees built around the creation and widespread online dissemination of outright false narratives ascribing unrest to foreign manipulation or separatist motives where none exist.

People take part in a rally in Hong Kong on December 22, 2019 to show support for the Uighur minority in China. ANTHONY WALLACE

“The Chinese government was not merely spreading fake news or disinformation. Rather, it seems to be practising a kind of reality engineering in which it is using its coercive and information machinery to generate enemies, be they Islam, an independence movement or imperialistic plots,” Wang argued.

“These imaginary enemies come at the expense not only of the countless individuals harmed in the process, but of finding real solutions to the discontent in Xinjiang and Hong Kong.”

That’s the unsatisfying, unsettled place we find ourselves heading into the 2020s, needing this beautiful, terrifying and tragically flawed beast to be better. Small wonder so many today voice dispassion for the platforms, annoyance at the algorithms and increasingly feelings of isolation and loneliness. Small wonder so many others have simply retreated into the tribe of like minds, blocking/unfriending themselves to a place where their sense of self-worth will not fall under routine attack.

If you are so fortunate as to find yourself gathered with friends or family over these holidays, maybe take a moment to observe how many and how often phones and other devices are in the hands of those you love. Everyone? All the time? Or are your humans still able to shut it all down, if only for a few hours? A worthwhile Canadian endeavour, that.

Meanwhile, let us all take at least some small solace that our accidental addictions are no match for that of dopamine-deficient Donald Trump, who last April vented at Twitter chief Jack Dorsey during a face-to-face meeting at the White House, evidently convinced the company was intentionally undercounting his followers. Trump allegedly complains regularly to insiders that his predecessor Obama cannot possibly command the world’s largest Twitter following (111 million) when Trump himself lags in 11th place (68 million), sandwiched between Justin Timberlake and Ariana Grande.

Harvard Medical School’s Haynes reminds us that lest it seem hopeless, none of us are helpless. It helps to be mindful of the trade-offs as we engage. It helps to think more about what we can bring to it and less about what we can take away. And yes, for some, it helps to spend a little less time on your phone. There’s no app for that, but there are strategies known to work.

“Doing things like disabling your notifications for social media apps and keeping your display in black and white will reduce your phone’s ability to grab and hold your attention,” notes Haynes.

“Above all, mindful use of the technology is the best tool you have. So the next time you pick up your phone to check Facebook, you might ask yourself, ‘Is this really worth my time?’”

Swedish climate activist Greta Thunberg arrives to takes part at a Friday for Future strike on climate emergency, in Turin, on December 13, 2019. AFP via GETTY IMAGES

Lastly, it’s worth reflecting how even now, a decade on, our new social spaces remain a veritable wild blue yonder, capable of amplifying in ways we never saw coming. Who among us envisioned the decade would end with a lone Swedish schoolgirl galvanizing and mobilizing millions the world over to the issue of climate change? Maybe, just maybe, we can still get this right.

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