Many recurring health stories this year centered on tensions in our relationships with technology, from vaccines to phones to healthcare exchanges. It was a fascinating, terrible, and heartening year, as always. Here are some of the stories that commanded a lot of discussion and will continue to factor in the year, and years, ahead.

Polio's Global Comeback

Global conflicts risk bringing polio, an infection that causes paralysis, back from near-total eradication. In Pakistan, suspicion that polio vaccinators are somehow harming children has fueled several killings of polio workers throughout the country’s tribal areas.

In Syria, a strain of polio originating in Pakistan has crippled more than a dozen children as the country's public health infrastructure has broken down after more than two years of civil war. Somalia, Afghanistan, and Nigeria have also seen periodic polio outbreaks.

New Challenges to Reproductive Rights

The pro-life movement gained strength in 2013. Thirteen states have recently passed restrictions shortening the time frame in which women could receive abortions, though federal judges later blocked some of the states' laws. Meanwhile, other regulations passed this year have forced a third of Texas' abortion clinics to close, leaving 20 facilities open in a state of 26 million people. Mississippi has just one abortion clinic remaining. This summer, there were reports that women in Texas’ Rio Grande Valley were crossing the border to Mexico to purchase misoprostol, a drug that induces miscarriages.

The Supreme Court is also hearing a case brought by Christian crafts purveyor Hobby Lobby, who says the Affordable Care Act’s mandate that the company cover contraception for employees would make them "morally complicit" in the "death of an embryo." The outcome could determine whether other businesses are required to offer birth control on their insurance plans.

Rethinking the Left Brain/Right Brain Paradigm

People who are brilliant artists but can't do long division may no longer have their brain structure to blame. A study of 1,011 people published in the journal PLOS ONE in August suggested that, contrary to the long-standing idea, there is no evidence that some people are either right-brained or left-brained. Though the authors did find that some brain functions occurred largely in one hemisphere or the other, they found no evidence that people used either hemisphere preferentially. What’s more, psychologist Stephen Kosslyn put forth a new theory that rather than left and right hemispheres, cognition is divvied up between "top" and "bottom" brain systems. Mind=blown. (Vertically).

Obamacare’s Problematic Roll-Out

The long-awaited exchanges, on which most uninsured Americans were intended to buy health insurance, landed with a thud in October in the form of the glitchy, barely functional Then, just when the tales of bureaucratic agony reached a fever pitch, thousands of people began receiving cancellation notices from their insurance providers because their plans didn't meet Obamacare’s minimum requirements. Meanwhile, Obamacare supporters are still hopeful that the law’s Medicaid expansion will improve health in low-income communities, and that some of the cancellees might qualify for subsidies on the exchange now that the website (mostly) works.

Meanwhile, many doctors and hospitals are seeing lower payments.

Football Feels Effects of Its Concussion Problem

Stories about the dangers of head injuries from football are not unique to 2013. Last year, The Atlantic’s Ta-Nehisi Coates wrote that he was done watching football, that even though he was a fan, his ethics couldn’t allow it. But this year saw the situation continue to deteriorate, even as the National Football League (NFL) tried to resolve it, settling an enormous lawsuit with more than 4,500 former players for $765 million, and instituting new rules for the 2013 season including a ban on tackling at training camps.

Meanwhile, ESPN recently reported that youth football league Pop Warner saw participation drop by 9.5 percent from 2010 to 2012, largely due to concerns about head injuries. Parents are growing more and more concerned about letting their kids participate in the most popular sport in the U.S.

The concussion controversy is spreading to other sports as well: Ten former National Hockey League players recently filed a lawsuit similar to the one the NFL just settled, claiming that the League did not do enough to prevent head injuries to players.

Conversation on Death Continues to Open

Most of our lives are spent ignoring the inevitable period at the end of the sentence. We beat death back with medicine for as long as we can, though even successful measures are just a stall. But some are starting to argue that this obsession with prolonging life is detrimental when patients are seriously suffering, that you can, in fact, live too long. When people die, they do it in hospitals instead of at home, and their bodies are embalmed to make them presentable, a "sanitization" of death that has existed in our culture since the 1800s. In addition to the debate on how to die with dignity, groups around the country are seeking to give people a relationship with death throughout their lives—hosting "Death Salons" and "Death Cafes" that discuss all aspects of death, from the funeral industry to academic theories about death to personal loss. The hope is that, by cultivating a personal relationship with death, we can start to be less afraid.

The Evolving Understanding of Depression

According to the Centers for Disease Control and Prevention, about 1 in 10 U.S. adults suffers from depression, and use of antidepressants has skyrocketed, increasing by 400 percent between 1988 and 2008. Earlier this year, a study done at Johns Hopkins University suggested that this apparent depression epidemic may be overinflated. Upon re-evaluating more than 5,000 adults who had been diagnosed with depression, it found that more than 60 percent of them did not fit the criteria for major depressive disorder (some—not all—could have been reasonably diagnosed with minor depression).

It can be hard to tell what is clinical depression and what is just sadness in the face of normal human challenges. On social media, Tumblr in particular, communities have sprung up that provide an outlet for sufferers, but can also glamorize depression in a way that experts say can perpetuate negative feelings, especially among adolescents.

Most recently, research has shown that there's a bit of a chicken-and-egg question when it comes to depression and insomnia, that the two can feed into and exacerbate each other. It's possible that cognitive behavioral therapy to improve a person’s sleep habits may actually improve their depression as well.

Widespread Criticism of New Psychiatric Categories

The latest (fifth) edition of the American Psychiatric Association's Diagnostic and Statistical Manual came out this Spring, and got a tepid response from many prominent mental health professionals. Tom Insel, the director of the National Institute of Mental Health, said: "A diagnostic approach based on the biology as well as the symptoms must not be constrained by the current DSM categories." Psychiatrist Gary Greenberg was outspoken in criticizing the book as being ascientific. Another study at Johns Hopkins found that a majority of people diagnosed with depression by one physician would not be diagnosed with depression by another. The field seems to be demanding more hard data and less subjective assessment.

HPV-Related Cancer Awareness

Michael Douglas said in May that he got his oropharyngeal cancer from HPV via oral sex. That was an emergent male voice in the HPV-related head-and-neck cancer world. Many people did not (do not) know that the two are related.

Also on this front, just within the last couple weeks, the American Board of Obstetricians and Gynecologists decided that OBGYNs can treat male patients, which is especially important for some HPV-related anal cancer screening and treatments.

Still the latest numbers we have say that most kids in the U.S. aren't getting the HPV vaccine, and that if American vaccination rates could be the same as those in Rwanda, it would mean 50,000 fewer future cancers in girls living today—of the cervix alone.

The Acceptance of the Selfie

To throw in a pop-cultural zeitgeist-y thing among so many grave medical topics, the public's acceptance of self-portraiture (Merriam-Webster's word of the year is selfie) changed interestingly over the course of just this year. It was well characterized by Jenna Wortham in The New York Times ("My Selfie, Myself"). What used to be widely written off as narcissistic and embarrassing is much more tolerated, even lauded as artful expression or confident self image in the bizarre landscape of social media. We did a post about young people taking selfies at funerals, and some people thought it was ridiculous, which is the pretty traditional reaction, but there was definitely a contingent of readers who thought it was a totally normal mode of healthy expression. It's not really a new one, either. Van Gogh painted many self-portraits. Well, maybe not the best example.

Still not everyone thinks selfies are great. This year, though, from Geraldo to Hillary Clinton to the Drake-hands guy to regular people, stories about them regularly inspired passionate feelings of every sort.

The Atlantic's Health Channel is edited by Julie Beck, Olga Khazan, and James Hamblin with production by Judith Ohikuare.