Tommy Wood
Physician and neuroscientist at the University of Washington; researches brain health, metabolism and athletic performance.
Tommy Wood did not write this page. What is this?
It collects the places they publish and what they have said there, each linked to the source. They have no account here. Is this you? Claim it, correct it, or ask us to remove it from ppll.
Where they publish
Beliefs
Korrents What they believe 26 beliefs — each backed by an exact quote.
Each is a — compiled by korrents.com, not by them: the one-line wordings are korrents', the quotes are theirs.
Recent
The adult brain's stock of neurons is essentially fixed, and that is no limit on learning, because plasticity is the changing of connections between the cells you already have.
But just because we have a fixed relatively fixed number of cells doesn't mean that we can't change the connections between those cells. And that's happening all the time. And that is, you know, the main principle of neuroplasticity.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
Neuroplasticity is as much the removal of connections as the growth of new ones, so pruning is a form of learning rather than a form of decay.
A lot of people don't realize that particularly brain development, but then also the refining of functions in the brain through neuroplasticity includes the pruning or removal of signapses. Often we think about it's all about growth and new connections, but actually it also involves the refining or removal of of other connections that aren't needed.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
Putting older adults into activities that are genuinely new to them improves cognitive function in randomised trials, with executive function the most reliable gain.
However, there's an increasing body of literature that shows that by engaging older adults in novel cognitive activities, you see improvements in function. So that can be language learning. Uh that can be uh complex like coordinative movement or exercise. You see the same things with um like musical training like people learning a new musical instrument or learning um musical theory trying to identify different patterns in music. And you see in randomized control trials improvements particularly in executive function that seems to be most common across those different interventions.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
Show 23 more
Training visual processing speed in later life lowers dementia risk two decades later, which continuing to do what you are already good at does not.
They just published a secondary analysis of the active trial that showed that um those who did processing speed training with uh booster sessions at one and three years had a significantly decreased risk of dementia 20 years later.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
Crosswords and sudoku are closer to meditation than to cognitive training, because they keep you focused without ever making you struggle.
Even if you're doing hard ones, if you look at the work of people like uh Gloria Mark, the things like crossword and sudoku, they're less of like a true cognitive challenge, right? It's it's almost has more of like a meditation meditative like effect, right? Which can be a good thing, right? So you're focused but not challenged really.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
Digital brain training makes you better at the training and at nothing else, which is the strongest argument against it.
This is one of the main arguments against online or you know digital brain training is that you get very good at doing that one specific thing but it doesn't transfer over to other areas of your life.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
Partner dancing, not puzzles, has the best evidence of any activity for improving cognitive function in older adults.
there are meta analyses of these interventions in older adults showing that ballroom and line dancing have the greatest effect on cognitive function. And so both of those require other people as well as learning you know various sets of of movements.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
We lose cognitive function with age largely because adults refuse to be bad at things, and so stop giving the brain the novel input that maintains it.
potentially one of the reasons why we lose lose cognitive function as we get older is because we stop giving our brain novel inputs or complex inputs that help maintain function, drive neuroplasticity. And I think one of the reasons that that happens is because adults hate being bad at things, right?
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
Flow is not required to perform at your best: a clutch state, in which you perform well and it still feels like hard work, is just as legitimate a peak state.
And both of those are perfectly reasonable states in which to perform. And assuming that you have to be in flow to perform just isn't true if you look at like how you know athletes perform in the moment.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
Learning cannot happen in flow, because getting better at a skill means working beyond the level at which you can express it.
If you want to get better at that skill, you have to work even further beyond your current capacities which which will move you out of flow, right?
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
How much a pianist practises, not how old they are, predicts how well they play, which makes skill decline with age mostly a training problem.
And what they [snorts] found was that the most important predictor of how well somebody performed at those piano specific skills was not their age, it was how much they practice.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
The 10,000-hour rule misreports its own source: 10,000 hours was how much expert violinists had practised by the age of twenty, and they were not experts yet.
The simple answer is what the study showed was that 10,000 hours was the average amount of time that an expert violinist had spent practicing by the time they reached 20 years old. That's what the study showed. They weren't even experts by that point.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
Nobody can do genuinely hard cognitive work for eight hours a day; the sustainable unit is one or two sessions of sixty to ninety minutes.
We kind of expect that we can go to work and we can work really hard for eight hours straight during the day, but like the brain doesn't really work like that.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
No single food explains the link between a Mediterranean diet and lower dementia risk, so what matters is overall diet quality rather than olive oil or avoiding meat.
And there was no food or you know olive oil or food group or you eating more or less meat that changed the relationship between the Mediterranean diet and dementia risk. So what that tells me is it's much more about whole foods.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
The relationship between energy intake and brain size is a bell curve: chronic caloric excess leaves you with a smaller brain, just as chronic restriction does.
And what they found is there's kind of this um bell-shaped curve between energy availability and brain volume. And in general, brain volume, right, the more the better, right, we think. And so if you're chronically calorically restricted, your brain is smaller um because you just don't have the resources to invest in, you know, the structure um and to maintain it. At the other end, you see the same thing. So if you're chronically in a chronic state of chloric excess, you also tend to have a smaller brain on average.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
Trials of omega-3s and of B vitamins keep coming back null because the two depend on one another, and supplementing either while the other is low does nothing.
But there are now at least three randomized control trials that have shown that omega-3 status and B vitamin status interact and they're dependent on one another. So, if you give uh B vitamins to somebody who has elevated homocyine, you bring down their homocyine, but they have poor omega-3 levels, you don't see any benefit.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
The evidence on nutrients supports exactly one instruction, do not be deficient, and nothing is known about pushing a level above the normal range.
I will say that the best evidence we have just says in reality don't be deficient. If you can reach that threshold of not being deficient or insufficient, maybe that's enough.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
Caffeine makes people feel that they are performing better on demanding cognitive tasks while they are actually performing worse.
So there there are studies that show that um uh giving people caffeine makes them [snorts] feel like they're performing better, but they're actually performing worse on certain cognitive tasks.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
How an athlete says they feel predicts their performance better than their HRV or any blood marker you can collect.
And we know that how you feel, so how an athlete feels is a much better predictor of their performance than their HRV or any of their blood test.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
High-intensity exercise improves hippocampal structure and function precisely because it releases a lot of cortisol, which is the opposite of the case made against hard training.
This study directly shows that working really hard, releasing a lot of cortisol in high-intensity interval training actually improves hippocample structure and function um over over time.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
Cardio and weights build different brains: aerobic exercise benefits the gray matter and the hippocampus, resistance training the white matter.
Whereas aerobic exercise on that kind of intensity spectrum we just talked about seems to particularly benefit the gray matter which includes the hippocampus. Resistance training seems to particularly benefit the white matter.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
Stress is the mechanism of adaptation rather than something to be minimised, and the case against it comes from conflating chronic stress with acute stress.
But the way that I think about it or I try and talk about it is that actually the stress response and this is as kind of Sier originally described it is stress drives adaptation.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
The dementia risk from short sleep starts below six hours a night, not below eight.
but I mean in reality when you look at the data on sleep loss and dementia risk The cut off is really around 6 hours. So if you're consistently sleeping fewer than 6 hours, that's where risk starts to increase.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
Cognitive decline is a staircase rather than a slope: the big drops happen after episodes of serious illness.
cognitive function doesn't just decline sort of linearly or steadily with age. It goes down, you know, a little bit on average, but the biggest decreases sort of happen stepwise after periods of significant illness.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
Cooling someone after a head injury does not help; what matters is stopping them from getting hot.
So there have been lots of studies where they've done cooling hypothermia in people after traumatic brain injuries and concussions hasn't really shown much of an effect. What seems to be important is preventing hyperothermia.
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
About half of all dementia is preventable, and most of that preventable half is Alzheimer's disease and vascular dementia.
we've gotten to a point now where it's generally accepted that potentially half of cases of dementia are preventable and I think the majority of that falls into those first two buckets Alzheimer's and vascular dementia
Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood Said 20 Jul 2026
What is a korrent?
A korrent is a belief a person has stated in their own words: one sentence stating the claim, backed by a quote and a source, kept at korrents.com.
Under a name here, the quoted block is what they actually said. The korrent beneath it is the claim those words support, in korrents' wording — tap it to see the record, its source, and who else holds it.
Nobody here wrote their own korrents. They are compiled from public statements, and a person can change their mind, which is recorded too.
About the English under a post
Some people here publish in a language other than English. Where they do, this site shows a machine translation beneath the post, in this typeface — the site's own, not theirs.
The post itself is never changed, moved or hidden: what is set in the serif above is exactly what the person published, and it is what to quote them on. A translation can be wrong in ways that matter, especially about tone.
Only the post's own words are translated. A quoted post, a linked article and a belief on korrents.com are left in their original language.