Richard Powers’s poignant new novel, “Bewilderment,” is a cri de cœur. Like his recent masterpiece, “The Overstory,” which won a Pulitzer Prize, “Bewilderment” deplores humanity’s destruction of the environment and the perverse incentives that make our descent toward universal suicide so difficult to stop.

But unlike “The Overstory,” with its sprawling network of interconnected plots, this is a hauntingly intimate story set within the privacy of one family trapped in the penumbra of mourning. Although there are allusions to a Trump-like fiend accelerating the country’s decay, Powers isn’t interested in exploring the full scientific and political complexity of our environmental catastrophe. Instead, “Bewilderment,” which is shortlisted for the Booker Prize and longlisted for a National Book Award, focuses on how that tragedy is perceived by one special little boy.

When the novel opens, an astrobiologist named Theo Byrne is camping with his 9-year-old son, Robin. The setting is bucolic but tinged with tragedy. Theo and his wife, a passionate animal rights lawyer, once spent their honeymoon in this forest, but two years ago she died in a car accident. Now, father and son are negotiating that tender border between reminiscence and grief. “Alyssa would’ve propelled the three of us forward on her own bottomless forgiveness and bulldozer will,” Theo says. “Without her, I was flailing.”

The whole novel comes across in that wounded, confessional tone, the voice of a man so overwhelmed that he can barely contend with the ordinary diversions of life. “Everything about parenting terrified me,” he says, and he’s got extra reasons to be concerned. His precocious son exhibits a strange set of contradictory behaviors. Noises unsettle him, except in the woods, where he can identify them with precision. He has trouble concentrating but memorizes enormous amounts of information and sits for hours to produce intricate sketches. Although he’s incredibly sweet, he sometimes explodes in uncontrollable rages.

Various specialists have suggested Asperger’s, OCD and ADHD. “I never believed the diagnoses the doctors settled on my son,” Theo says. “His second pediatrician was keen to put Robin ‘on the spectrum.’ I wanted to tell the man that everyone alive on this fluke little planet was on the spectrum. That’s what a spectrum is.” Alarmed by the overprescription of psychoactive drugs to muzzle and normalize atypical children, Theo rejects them all and develops what he admits is a crackpot theory: “Life is something we need to stop correcting,” he insists. “My boy was a pocket universe I could never hope to fathom.”

But fathoming other universes is the essence of Theo’s job. He studies the infinitesimal fluctuations of light from space in hopes of locating alien planets capable of supporting life. Laced throughout the novel are gorgeous glimpses of faraway worlds — imaginative nighttime stories that Theo tells Robin about beings who have two brains, fishlike organisms with religious rites and civilizations that exist along a strip between boiling and freezing.

“They share a lot, astronomy and childhood,” Theo says. “Both are voyages across huge distances. Both search for facts beyond their grasp. Both theorize wildly and let possibilities multiply without limits. Both are humbled every few weeks.”

But as attuned as Theo is to his son, love and patience alone will not make Robin neurotypical. As the boy’s outbursts grow more violent, Theo attracts more critical attention. If you’re the parent of a child with special needs who’s felt the cold procrustean hands of the public school system, you know what this father is up against. When the principal threatens to get Child Services involved with Robin’s case, Theo is willing to try anything to keep from medicating his son into an appropriate state of docility.

At this point, the story takes a turn down what we might call Powers Lane — that avenue of almost-mystical cutting-edge science that we’ve come to expect from the author’s cerebral novels. Desperate to keep Robin off psychoactive drugs, Theo turns to an old friend of his wife’s who is developing an experimental therapy called decoded neurofeedback or DecNef. It’s a noninvasive procedure that involves placing patients in an fMRI machine and training them to pattern their own neural activity to match some standard, presumably healthier mental state.

For fans of Powers’s earlier novels, this should get all their synapses firing. They’ll remember that “Galatea 2.2” (1995) revolves around the development of an artificial brain. In “The Echo Maker” (2006), a young man suffers a traumatic head injury that alters his memory. And in “Generosity” (2009), an Algerian woman may possess the genetic key to happiness. But if those earlier novels sometimes felt like auditing a graduate course in neurology, “Bewilderment” holds forth in a shadowy forest of fables.

The moment 9-year-old Robin responds positively to DecNef treatment, the lab director hits upon a curious idea: Why not use old neural patterns recorded by Robin’s mother to train the boy in attaining ecstasy? Sure enough, soon Robin is communing with his dead mom’s brain — or at least its recorded neural patterns. In a matter of weeks, he has acquired his mother’s knowledge of the natural world and her intense love for it.

This mother-son spirit mingling may be incredibly lovely, but it’s also irreducibly creepy. And there’s a high risk of sentimentality here: the precious Messiah child mewing his little Whitmanesque profundities at us about the unity of all life. More problematic still is a corny story line in which Theo suspects that the lead neurologist might be carrying on some kind of adulterous affair with his dead wife’s brain print. All this neurological mumbo-jumbo creates a clammy atmosphere for what is, at its heart, a tender story about a child who responds to the plight of our planet just as passionately as we all should.

Unfortunately, “Bewilderment” goes out of its way to cast the tale of Robin’s miraculous evolution as a green version of Daniel Keyes’s “Flowers for Algernon.” That classic tear-jerker has taught generations of seventh-graders that the only thing worse than being intellectually disabled is getting smarter and then becoming intellectually disabled again.

Powers’s thoroughly modern fable of environmental mourning hardly needs to dredge up that cringeworthy antecedent. It feels like just one more bit of fantastical melodrama that dilutes the potential power of “Bewilderment.”

Ron Charles writes about books for The Washington Post and hosts TotallyHipVideoBookReview.com.

Bewilderment

By Richard Powers

W.W. Norton. 278 pp. $27.95