The assault on young people’s brains
At the risk of seeming curmudgeonly, multiple lines of research are converging on the notion that younger people are getting dumber.
Older adults may seem feeble-minded when struggling with devices that were only introduced in their mid-lives; Gen Z grew up with them and take to them naturally.
We tend to look down on previous generations whose technology seems primitive by comparison with our sophisticated gadgets. But think about what it took to get under the hood of a balky Model T, navigate a Viking longboat by the stars, mine and chip flint to construct the sharp blade of a Paleolithic axe, or predict solar eclipses with an Aztec calendar.
Case in point, it’s generally acknowledged that IQs, which progressively increased over the 19th and first half of the 20th centuries, are now in retreat.
So, too, are young people’s subjective assessments of their memory abilities: “Memory Problems Are Surging in Adults Under 40, Large US Study Finds”, reports ScienceAlert.com:
“A US team led by University of Utah neurology researcher Ka-Ho Wong found that those aged 18–39 experienced the biggest uptick in cognitive disability in the past decade, after analyzing survey data from more than 4.5 million people. Overall, the proportion of US adults reporting serious cognitive difficulties rose from 5.3 percent to 7.4 percent between 2013 and 2023. For those under 40, the rate nearly doubled, jumping from 5.1 percent to 9.7 percent across the same period.
It is said that depression may color a person’s self-appraisal of their cognitive abilities, and depression rates are certainly soaring among young people, but the authors of this study deliberately excluded young people who carried that diagnosis.
So, what’s going on?
Shortcuts: As a student, I used to disappear into the library “stacks” and pore over weighty volumes to suss out information. I’d then synthesize what was relevant—often in long-hand—to craft a well-argued term paper.
Nowadays, AI is taking over. It’s the way of the future; most college students leverage AI to complete the majority of their assignments. It’s the modern equivalent of those paid services that cheaters used to employ to write their papers for them, instead of relying on their own grunt work. A recent review, “Generative AI: the risk of cognitive atrophy”argues that:
“Using ChatGPT to write an essay reduces the cognitive engagement and intellectual effort required to transform information into knowledge, according to a study. The study also showed that 83% of AI users were unable to remember a passage they had just written for an essay. Other studies show that individual gains can be significant when authors ask ChatGPT to improve their texts, but that the overall creativity of the group decreases.”
We’re even losing our evolutionary fine-tuned ability to navigate, relying instead on voice-activated GPT turn-by-turn directions.
It may seem quaint to suggest this, but handwriting tends to reinforce learning.
A Psychology Today article reports, “ . . .accumulating evidence suggests that not learning cursive handwriting may hinder the brain’s optimum potential to learn and remember.”
Nowadays, few schools bother to teach kids cursive or even block letters, yielding to the convenience of typing on screens. Moreover, word prompts substitute for spelling and grammar knowledge, calculators do our arithmetic for us, and even the most incoherent essay can be cleaned up with ChatGPT. And in place of nuanced communication, we’re supplied with instant emojis.
Screens: We Baby Boomers shouldn’t talk; we were glued to TV screens as we grew up. Our parents, accustomed to the “theater of the mind” of radio that encouraged imagination, disparaged TV as an unproductive time-suck.
Little could they imagine the quantum leap that turbo-charged social media, accessed on ubiquitous mobile devices, would represent for their grandkids and great-grandkids. Best-selling author and social psychologist Jonathan Haidt(author of The Anxious Generation and The Coddling of the American Mind) has famously inveighed against the ravages of readily-available, addictive, fast-paced distractions for the attention spans of young people.
Brain-drainers: An unprecedented proportion of young people are reliant on psychoactive drugs. Adderall and similar medications that address ADHD, when properly prescribed, can improve focus and learning. But illicit use of has soared; in a recent study, 6.9% of students reported “non-medical use”— i.e., without a prescription ostensibly to boost performance—of Adderall; 7.8% resorted to amphetamines. This introduces the potential for excessive dosing and abuse.
“Adderall addiction can negatively impact memory. Chronic misuse disrupts the brain’s dopamine regulation, which is crucial for memory formation and retention. This can lead to difficulties with short-term and long-term memory, particularly when the drug is not in the system. Over time, addiction may impair cognitive functions, including recall and learning ability, exacerbating reliance on the drug to perform cognitive tasks.”
Then there’s the impact of more readily accessible and powerful cannabis, made kid-friendly via vape pens, beverages, and gummies. 26% of 12th graders, 16% of 10th graders, and 7% of 8th graders in the U.S. reported using marijuana in the past year. Pot is notorious for its adverse effects on the brain. The CDC reports:
“Using cannabis before age 18 may affect how the brain builds connections for functions like attention, memory, and learning. Cannabis’s effects on attention, memory, and learning may last a long time or even be permanent . . . Youth who use cannabis may not do as well in school and may have trouble remembering things.”
Binge-drinking has long been enshrined as a youthful rite of passage. Although alcohol use among young people is declining, it still exacts a toll on brain health. A review states:
“There is a growing body of literature that demonstrates alterations in cognitive performance, and in brain structure and function, particularly in the frontal networks and hippocampus, in adolescent and young adults with alcohol use disorders (AUDs) and with heavy episodic alcohol consumption histories.”
You are what you eat: Ultraprocessed foods (UPFs) are eaten by kids at levels unprecedented in human history. By some estimates, upwards of 60% of the calories consumed by young people are from refined carbohydrate- and artificial ingredient-laden meals and snacks. There’s a direct relationship to brain health, according to a recent review:
“ . . . in early childhood, inadequate nutrition is a key risk factor for developmental impairments, influencing cognitive function and long-term health outcomes. Adolescence, another critical stage of brain maturation, is particularly susceptible to the effects of micronutrient deficiencies, often exacerbated by diets high in UPFs, which can impair neurodevelopment and cognitive performance . . . Early-life exposure to UPFs may contribute to lasting cognitive deficits and increased susceptibility to mental health disorders, emphasizing the urgent need for targeted dietary interventions and public health strategies aimed at pregnant women, children, and adolescents.”
Some of diet’s effects on the brain are mediated via the microbiome. Gut-brain connections work optimally when bacteria are diverse in the intestine; kids these days are routinely subject to several antibiotic prescriptions per year—most of them inappropriate.
Obesity weighs on the brain: The relationship between childhood obesity and impaired cognitive development is well-established. The incidence of childhood overweight and obesity is soaring. Researchers report:
“Within this cohort of typically developing children, early-life weight status was inversely associated with children’s perceptual reasoning and working memory scores and possibly with full-scale intelligent quotient scores.”
Sleep deprivation: Kids today are overbooked and tempted by social media to stay up late scrolling and texting. It’s estimated that over the course of the last century, the average child has lost over one hour of nightly sleep. A Chinese study found:
“Overall, insufficient sleep impairs adolescents’ cognitive abilities, particularly in areas such as attention, memory processing, learning motivation, and executive function, all which are critical factors for academic success. Short sleep duration and poor sleep quality were the sleep metrics most strongly associated with a higher likelihood of lower GPA.”
Lack of physical activity: Why waste time on the playground when that valuable time could be better spent in the classroom? Traditional “P.E.” has become an endangered species in schools, and youngsters these days are more immersed in virtual reality via screens than in outdoor play.
That’s to their detriment: Cultivation of motor skills is acknowledged to promote brain network development in children, which translates to better academic performance.
Stress: It’s hard to argue that this generation of children lives in more stressful times than their predecessors; there are fewer direct threats from war, famine, and disease. But modern life has ushered in unprecedented alienation and rootlessness for many young people. “Measuring up” has never been harder, and FOMO abounds. Persistent high levels of the stress hormone cortisol are known to shrink the hippocampus, the memory center of the brain.
Every breath you take: There’s compelling evidence that air pollution adds to kids’ toxic burden; developing brain regions are more sensitive to the adverse effects of air particulates in children than adults. University of Washington researchers report:
“Our study extends earlier findings that have raised concerns about impaired behavioral functioning and cognitive performance in children exposed to NO2 and PM2.5 in utero and in early life.”
Add to that exposure to ever-present environmental chemicals and heavy metals and you have a recipe for impaired neuronal efficiency in early life.
With the many threats assailing them, is it a wonder that kids cognitive performance is suffering? And that’s a dire portent for the future, when the current generation of children attain middle-age, compounding the insupportable burden of neurodegenerative disease already straining our medical system.