David Kessler, former head of the FDA, has a new book out about mental suffering. (Peter Turnley)

David A. Kessler, the former head of the FDA, was on a plane not long ago. He planned to spend the long flight working on a new book, laying out his theory of how us humans can be totally “captured” by thoughts, memories, even sounds.

Kessler thinks the process offers a new explanation for mental suffering — and maybe even mass shootings.

“I open my laptop, but as soon as I do, I begin to hear the voices of the two men sitting next to me rapt in a loud conversation,” Kessler writes. “To me they are talking at the decibel level equivalent to truck traffic.”

He tries to shift his focus to the monotonous sounds of the roaring engines. It doesn’t work. He simply cannot stop focusing on those voices. So there he was, stuck on a long flight, unable to write about capture because he was captured.

Kessler tells the story at the outset of his new book, “Capture: Unraveling the Mystery of Mental Suffering.” After taking on big tobacco as Food and Drug Administration commissioner, then tackling obesity in his bestseller “The End of Overeating,” Kessler has turned his prodigious intellect toward understanding why “our rational minds feel as though they’ve been hijacked by something we cannot control.”

 (courtesy of HarperCollins) (Courtesy of HarperCollins)

His noisy airplane ride didn’t lead to depression or suicide or shooting at random, but it did illuminate how someone could get to that point. “Simply put: A stimulus — a place, a thought, a memory, a person — takes hold of our attention and shifts our perception,” Kessler writes. “Once our attention becomes increasingly focused on this stimulus, the way we think and feel, and often what we do, may not be what we consciously want.”

I met with Kessler the other day to discuss the book, particularly a long section about capture and violence, which piqued my interest while reporting a story about whether mental illness is to blame for the phenomenon of mass shootings, as so many politicians often argue. Simply put: not very often.

So what is? And why is mental illness blamed not just by politicians but also the American public?

“What they’re really saying is, ‘I don’t understand,’ ” Kessler told me.

People assume that mass shooters must be insane to carry out an insane act. The vast majority of these shooters aren’t, though. They’re jilted, seeking revenge or fame (or both), and very often they have antisocial and paranoid personalities. Some experts speculate that mass shooters, who are almost always men, are suffering from “damaged masculinity.” Shooting random strangers becomes a means to an end.

But what if mass shootings are actually a form of relief, a release from being captured?

Kessler says capture has three elements: “narrowing of attention, perceived lack of control, and change in affect, or emotional state.” And sometimes, the feeling is so overwhelming that it’s accompanied by an urge to act. It works like this, Kessler writes:

When we are drawn to a particular stimulus, we act in response to a feeling or need aroused by it. Every time we respond, we strengthen the neural circuitry that prompts us to repeat these actions. As we continue to react in the same ways to the same stimulus over time — thereby sensitizing the learning, memory, and motivational circuitry of our brains — we create emotional and behavioral patterns. Our thoughts, feelings, and actions begin to arise automatically. What started as a pleasure becomes a need; what was once a bad mood becomes continuous self-indictment; what was once an annoyance becomes persecution. This process of neural sensitization occurs, and grows stronger, over the course of a lifetime. It becomes increasingly difficult for us to resist its pull. Eventually, what captures us can become so concentrated and overwhelming that, in its most drastic forms, it feels as if we are being driven by something outside our control.

Kessler offers various examples of extreme violence, such as the crimes of Unabomber Ted Kaczynski, the assassination of Robert F. Kennedy, and several mass shootings, including the 1999 massacre at Columbine High School in Colorado. Eric Harris, the ringleader of the attack, was not known to be mentally ill. In examining the lengthy writings Harris left behind, Kessler says it is clear that Harris was captured by perceived injustices and personal slights among his peers. Kessler writes:

Eric turns his anger over a personal wound into an indictment of human existence. Grandiosity, that black mirror reflection of deep-seated insecurity, is a potent delusion. The recurrent spasms of revulsion in this yearlong account of Harris’s rage recur like building waves of nausea.

For months, the rage builds. And then he hints at murder, writing that “the human race isn’t worth fighting for, only worth killing.”

Two months later, Harris begins to write specifically about murder. Again, it isn’t just revenge; he imagines himself a lone Nietzschean figure who has overcome the world, taking responsibility for his actions and fully identifying with his absolute, amoral freedom. He boasts of how his crimes will define him: “I know I could get shot by a cop after only killing a single person, but . .  . I chose to kill that one person so get over it! It’s MY fault! Not my parents, not my brothers, not my friends, not my favorite bands, not computer games, not the media. IT is MINE!” With the passing months, Eric’s hunger to kill grows more and more encompassing.

Shooting released him from capture.

Kessler acknowledges that capture certainly isn’t the only force at play in mass shootings and mental suffering more broadly, including depression, anxiety or a complete separation from reality. But even the clearly delusional are captured — by voices nobody else hears or people who don’t actually exist.

Kessler hopes his book persuades policy makers and the public to “really get past the labels and understand the mechanisms at play.” He also wants the public to know that capture is a force for good. You can be captured by art, religion, being a great parent, whatever. But swapping bad captures for good ones is difficult. At the end of the book, Kessler writes:

When we understand capture for what it is, a neural mechanism that both influences and is influenced by our experiences, we can become more than passive chroniclers bound to unhappy or troubling narratives. By becoming aware of the ways in which we deploy our attention, we may even develop a beneficial flexibility of mind, one that allows us simultaneously to tell varied, sometimes even contradictory stories.

We can influence this process not by accepting a static diagnosis, such as “anxiety” or “depression,” but by actively changing what occupies our attention. It is possible to put ourselves in the way of a more positive influence, and its attendant stimuli, in order to overcome a prior capture. This happens, in effect, when the new form of capture becomes so important to us that the last one loses its magnetism.

In other words, if some loud talkers are keeping you from working on your next flight, go get captured by a good book.