Accelerate Learning & Increase Cognitive Capacity | Dr. Tommy Wood

A six-month study in older adults compared low-intensity exercise, treadmill work resembling zone 2, and Norwegian 4×4 high-intensity intervals performed three times per week. The interval protocol used four-minute efforts at 85–95% of maximum heart rate with three-minute rests. According to Tommy Wood, both the interval and zone 2 groups improved fitness, while the interval group showed stronger gains in hippocampal function and better preservation of hippocampal structure on MRI. The reported benefit persisted for five years after the intervention. The conversation presents this as evidence from one study, not a universal prescription for every listener.

The episode frames neuroplasticity as the brain’s ongoing response to experience: synapses can form, strengthen, weaken, or be pruned. Wood distinguishes this from neurogenesis. The fact that adult brains produce few new neurons in most regions does not mean the connections among existing neurons are fixed; those connections continue to change as people learn and remember.

The opening exchange also sets up the episode’s wider scope: Huberman and Wood plan to examine how learning states, exercise, and other science-based approaches may support focus, skill expression, and neuroplasticity. The introduction describes these as topics for discussion, rather than claiming that any single tool guarantees improvement.

The discussion rejects a simple equation between adult learning and making new neurons. Huberman notes that the adult brain largely retains its existing cells, while Wood emphasizes that plasticity also involves changing connections among those cells. For motor learning, such as improving at billiards, Wood says both sides matter: useful connections can be strengthened while connections that reduce accuracy or interfere with an intended movement can be weakened or removed. He does not claim that pruning accounts for most improvement.

The speakers then ask how to maintain cognitive function with age: keep exercising, continue familiar activities, or try unfamiliar skills. Wood describes evidence for continuing cognitively demanding hobbies, including lectures, volunteering, reading, and crosswords. These findings are observational, so they may partly reflect reverse causation: people who retain function may be more able to keep doing activities they enjoy.

Wood also points to intervention studies in which older adults learned languages, practiced coordinated movement, or engaged in music training. Randomized trials report cognitive gains, especially in executive function. He mentions online training studies as another source of evidence but distinguishes targeted practice from broader activities that combine several demands. The exchange therefore supports neither an exclusive “use what you have” rule nor a claim that novelty alone is enough; it presents continued engagement and appropriately challenging new learning as potentially complementary.

Wood qualifies the case for novelty: people who maintain cognitive function may simply be more able to keep doing activities they enjoy, so observational associations can run in both directions. Still, he points to intervention research in older adults where novel activities—language learning, coordinated movement, and music—were associated with cognitive improvements. Randomized trials most consistently found gains in executive function.

The conversation then turns to multicomponent programs. The Australian Maintain Your Brain study focused mainly on people in their 50s and 60s and tailored interventions across diet, physical activity, cognitive behavioral therapy for participants with potential mental-health concerns, and online brain training. Wood describes the US POINTER study in adults in their 60s and 70s as similar in broad outline to Finland’s earlier FINGER trial: diet, exercise, cardiovascular risk monitoring and treatment, and cognitive training. These programs test packages of supports, so their results do not isolate the effect of any one component.

For cognitive training specifically, Wood discusses BrainHQ and the older ACTIVE trial. ACTIVE compared memory training, reasoning exercises, and visual processing-speed tasks with a control group. A secondary analysis, as described in the interview, found a lower dementia risk decades later among participants who received processing-speed training with booster sessions at years one and three. Wood also notes other research linking this training to cholinergic signaling, while the episode distinguishes processing speed from simple reaction time: processing speed includes how quickly a person can interpret and remember information, not just respond to a visual cue.

Wood distinguishes reaction time from processing speed. In a study of roughly 1.2 million people discussed in the episode, average reaction time began to slow around the thirties and declined further after about sixty, while processing speed was more stable until around sixty. Processing-speed tasks require people to take in briefly presented information, then identify and remember what appeared and where; they therefore involve interpreting information, not merely reacting to a cue.

When Huberman asks whether people should make familiar activities harder or change domains, Wood says the answer depends on the activity. Crosswords and Sudoku may be engaging or meditative without providing much cognitive challenge. To build capacity, he suggests activities that require both focus and challenge. A new sport can combine motor learning, social interaction, and visual and auditory processing; those demands may offer broader transfer than becoming skilled at one narrow digital training task. The speakers present this as a rationale for varied, complex skills, not proof that every sport will transfer equally.

Asked for practical examples, Wood says the components need not all come from one activity: exercise and skill learning can be pursued separately, and learning a language is another option. He singles out dancing as a promising combination, pointing toward its mix of movement and other demands. The principle running through the exchange is to add a meaningful challenge that stretches current ability, while matching the activity to what a person is already doing and willing to sustain.

Wood identifies dance as a particularly rich activity because it can combine physical exercise, learning movement sequences, social interaction, and listening for musical timing. He cites meta-analyses in older adults in which ballroom and line dancing showed especially large cognitive effects. Other complex activities—such as ball sports, board sports, team sports, martial arts, and creative or visual arts—may also combine several demands, including motor coordination, reaction to a changing environment, and social engagement. The range of evidence differs by activity, and the conversation does not establish a direct ranking across all options.

The episode also treats embarrassment as a practical barrier to trying new skills. Wood argues that mistakes and the discomfort of being a beginner are part of learning. Taking a class where everyone is learning together may make that discomfort more manageable and even fun. He connects this point to the possibility that adults avoid novel or complex activities because they dislike being bad at something, which can reduce the varied inputs that support continued learning.