You wake up, ask an AI to summarize the news, generate a gym plan, even pick breakfast macros. On the commute, maps tell you every turn. At work, autocomplete drafts your emails; a chatbot outlines your report. It’s smooth. But later, you can’t recall the headlines you read, or the route you drove. The day felt efficient—yet mentally thin.
Cognitive scientists have a name for this: cognitive offloading—using external tools to do mental work that our brains could do themselves. Offloading isn’t inherently bad; it’s often smart. But frequent, effortless offloading can decrease the very practice our brains need to stay sharp. PubMedCell
Consider navigation. In a UCL study, when people followed a satnav, the hippocampus—the brain’s map-making hub—showed little engagement compared with navigating themselves. Separate research on London taxi drivers (“The Knowledge”) found structural changes in the hippocampus after intense spatial learning. Translation: when we let tools decide the route, our “mental map” does less work—and learns less. University College, London, PubMed
Now add AI. A 2025 meta-analysis across 51 studies found AI tools can boost task performance and perceptions of learning, but they also lower mental effort—great for speed, not always for deep encoding or long-term retention. A 2024 systematic review reached a similar conclusion: AI often improves grades and confidence while reducing cognitive load, which can blunt the “desirable difficulties” that make learning stick. Nature, ScienceDirect
So yes—AI can make you better at getting things done, but worse at practicing the skills that make your mind resilient. What’s the antidote?
Decades of learning science show that effortful retrieval (recalling, not rereading) and generation (producing answers, not recognizing them) create durable memories and flexible thinking.
Well-designed puzzles naturally enforce both. That’s why they’re more than idle entertainment—they’re a cognitive gym.
Put simply: effortful puzzles help you practice the very skills AI tends to erode—working memory, focus, and problem-solving.
You don’t need hours. You need 10–20 focused minutes of effortful problem-solving that makes your brain retrieve and generate. Pair that with conscious AI use (as a co-pilot, not a chauffeur).
Tip: If you’re stuck, use AI for a hint, not a solution—ask for a Socratic question (“What rule applies in row 7?”). This keeps effort (and learning) with you.
AI itself isn’t toxic. The problem is effortless offloading—outsourcing navigation, writing, recall—so your brain practices less. Studies show tool-use can downshift engagement in key brain systems (e.g., hippocampus with GPS), and AI research finds better grades with lower mental effort—great for speed, not necessarily for durable learning. University College London
PubMed
Nature
ScienceDirect
No single puzzle “prevents” dementia. But an RCT shows crosswords improved cognition and reduced brain atrophy in people with MCI, and large observational studies link frequent puzzles (including Sudoku) with better cognitive performance in older adults. evidence.nejm.org
news-archive.exeter.ac.uk
Hard enough that you struggle productively—where you must retrieve or generate (not guess or breeze through). That “desirable difficulty” is what strengthens memory. SAGE, Journals, CiteSeerX
Perfect. Short, effortful sessions beat long, passive ones. Do one mid-level Sudoku or a half cryptogram, then write one sentence about your method.
The Story You’ll Tell Yourself in 2 Weeks
Day 1 you’ll feel rusty. By Day 5 you’ll catch yourself holding more possibilities in mind. By Day 10 you’ll navigate to a café without Maps. By Day 14 you’ll notice work emails draft faster—because your brain, not your bot, did the thinking first. That’s the point: you’re not quitting AI—you’re re-training your mind to stay in charge.
When you’re ready, start here:
Share this with the friend who “lets AI do it faster.” Ask them to race you on today’s puzzle—many readers love turning this into a friendly daily duel. Brains grow in the ring, not on the sidelines.
A suggested routine includes a 2-minute warm-up with intention setting, 10-15 minutes of effortful puzzles like Sudoku, cryptograms, or word-webs, and a 2-3 minute reflection on how you solved the puzzles. During this, use AI sparingly for hints or critique, not solutions, to maintain cognitive effort and build resilience.
Puzzles should be challenging enough that you struggle productively, meaning you need to retrieve or generate answers rather than guess or breeze through. This ‘desirable difficulty’ boosts your memory strength, supported by research from SAGE Journals, Journals, and CiteSeerX.
No single puzzle prevents dementia, but an RCT shows that crosswords improve cognition and reduce brain atrophy in people with mild cognitive impairment. Large observational studies also link frequent puzzles like Sudoku to better cognitive performance in older adults, according to evidence from NEJM and Exeter University.
AI itself isn’t toxic. The problem is effortless offloading—outsourcing navigation, writing, recall—so your brain practices less. Studies show tool-use can downshift engagement in key brain systems (e.g., hippocampus with GPS), and AI research finds better grades with lower mental effort—great for speed, not necessarily for durable learning. University College London, PubMed, Nature, and ScienceDirect provide research evidence supporting this.
Sudoku can be a powerful focus tool if you live with ADHD, but only when…
There’s something oddly hypnotic about scrolling during the holidays. You sit down for a moment…
Why ADHD Brains Click with Sudoku If you’re an adult with ADHD, you already know…
Sudoku is one of the simplest brain games to play — but oddly one of…
If you don’t really care about your brain, feel free to skip this article.Seriously. Because…
You ask ChatGPT to summarise a book, DALL·E to imagine a scene, or Google Bard…