#257 ‒ Cognitive decline, neurodegeneration, and head injuries: mitigation and prevention strategies, supplements, and more | Tommy Wood, M.D., Ph.D.
Dr. Tommy Wood, Assistant Professor of Pediatrics and Neuroscience, discusses age-related cognitive decline and dementia prevention. He highlights the importance of cognitive demand, lifestyle choices, nutrient status, and physical strength, also covering strategies for mitigating damage and supporting recovery from head injuries.
Deep Dive Analysis
19 Topic Outline
Tommy Wood's Background and Research Interests
Understanding Age-Related Cognitive Decline and Dementia
Components of Cognition: Memory, Executive Function, Processing Speed
Root Causes of Age-Related Cognitive Decline
The Importance of Cognitive Demand and Avoiding Multitasking
Formula 1 Drivers as a Model for High Cognitive Demand
Strategies for Mitigating Cognitive Decline in Middle Age
Cognitively Stimulating Activities: Brain HQ and Open Skills
Neuropathology of Alzheimer's Disease: Amyloid and Tau
Discordance Between Amyloid Pathology and Cognitive Symptoms
Focusing Dementia Prevention on Lifestyle and Environment
Benefits of Lowering Homocysteine and Boosting Omega-3s
A Unifying Theory of Dementia: Upstream Factors
The Critical Role of Muscular Strength in Dementia Prevention
Head Injuries: Concussions vs. Traumatic Brain Injuries (TBIs)
Short-Term Management of Concussion: Thermoregulation
Hyperbaric Oxygen Treatment for TBI: Efficacy and Limitations
Supplements for TBI Recovery and Resilience: Creatine, DHA, Choline
Cognitive Demands and Performance Interventions for F1 Drivers
10 Key Concepts
Age-Related Cognitive Decline
A general, linear decrease in standardized cognitive function (executive function, working memory, processing speed, reaction time) observed across large populations with increasing age. Historical memory is often an exception, showing more preservation.
Memory Encoding
The initial process by which the brain recognizes and stores new information, often involving acetylcholine signaling. This process appears to be particularly impaired in individuals experiencing pathological cognitive decline.
Memory Retrieval
The process of accessing stored information. Retrieval speed tends to slow down with age, potentially due to the accumulation of more information over a lifetime, making specific data points harder to locate.
Cognitive Demand
The mental effort or challenge placed on the brain. Similar to physical exercise, applying appropriate cognitive demand can drive plastic reorganization and increase functional capacity, but it requires periods of recovery and adaptation.
Multitasking (Task Switching)
The act of rapidly shifting focus between different complex tasks. For most people, this is inefficient due to a 'loss function' or time penalty incurred when the brain reorients itself to a new task, reducing overall productive focus.
Open Skill vs. Closed Skill Physical Activity
Open skill activities (e.g., dancing, table tennis) involve reacting to a dynamic, unpredictable environment and other people, leading to greater cognitive improvements. Closed skill activities (e.g., stationary biking) are repetitive and unidirectional, offering less cognitive stimulus.
Amyloid Plaques and Tau Tangles
Neuropathological hallmarks of Alzheimer's disease, consisting of aggregated amyloid-beta protein found outside neurons (plaques) and hyperphosphorylated tau protein found inside neurons (tangles). These are primarily observed in the medial temporal lobe.
Panthos (Pathological Anthos)
A theory suggesting that amyloid-beta accumulates *inside* neurons within failing lysosomes, leading to cell death and leaving plaques as 'tombstones' of dead neurons. This contrasts with the traditional view of amyloid as primarily an extracellular accumulation.
Concussion (Mild Traumatic Brain Injury - MTBI)
A head injury resulting from the transmission of force to the brain, causing a disturbance of neuronal function. Symptoms can range from mild (e.g., headache) to severe and long-lasting (e.g., photosensitivity, processing difficulties), depending on the impact.
Second Impact Syndrome
A phenomenon where a second head impact, even a seemingly minor one, has a disproportionately severe effect due to the brain being vulnerable after a prior concussion. This increased vulnerability may be linked to depleted brain creatine levels.
9 Questions Answered
As people age, there is a pretty linear decrease in standardized cognitive function across most domains, with the exception of historical memory, which tends to be more preserved.
Memory involves two main parts: encoding new information and retrieving stored information. While encoding can be impaired in pathological decline, retrieval speed slows with age, possibly because the brain accumulates more information, making it harder to access specific pieces.
No, humans generally cannot multitask effectively by switching focus rapidly between complex tasks. This 'task switching' leads to a significant loss of productive time as the brain constantly reorients itself, offering minimal beneficial cognitive stimulus despite feeling busy.
A Lancet Commission report estimated that 40% of dementia is preventable through modifiable lifestyle factors, and this is likely an underestimate as it didn't include factors like sleep and nutrient status, or account for interactive risk factors.
Elevated homocysteine and low omega-3 (DHA) status are independently associated with increased risk of cognitive decline and brain atrophy. Supplementing with B vitamins to lower homocysteine and increasing DHA intake together appear to be synergistic in supporting neuronal membrane function and reducing risk.
Muscular strength acts as a direct neuromuscular stimulus, promotes glucose regulation, releases myokines that support brain function, and reduces systemic inflammation. Improvements in strength, even in older adults, correlate with better white matter connectivity and cognitive function.
The most critical short-term management involves thermoregulation, specifically preventing fever, for 24 to 72 hours after the injury. Keeping the core body temperature at or below 36.5 degrees Celsius is important, as a hotter brain after injury worsens outcomes.
While there's a possibility of benefit in the chronic phase (weeks to months post-injury) with multiple sessions, evidence is limited by uncontrolled studies and difficulty in creating proper placebo groups. Hyperbaric oxygen can be detrimental in the acute phase due to increased oxidative stress.
Creatine (prophylactic loading dose of 20g/day for a week, or 5g/day maintenance), DHA (2-6g/day), and Citicoline (1-2g/day post-impact) are worth considering. Creatine can increase brain creatine levels, DHA supports neuronal structure, and choline may improve neuropsychological outcomes.
15 Actionable Insights
1. Lower Homocysteine, Boost DHA
To significantly reduce the risk of cognitive decline and brain atrophy (by 20% or more for each factor), measure your homocysteine and omega-3 (DHA) levels. If homocysteine is above 11-13, supplement with methylfolate, methyl B12, and B6; simultaneously, ensure 1-2 grams of high-quality DHA daily, as these nutrients synergistically support neuronal membrane health.
2. Engage in Resistance Training
Implement a basic resistance training program, even in older adulthood, to improve white matter connectivity, cognitive function, regulate blood sugar, and reduce systemic inflammation through myokine release and hormetic effects. This intervention offers significant benefits for both cognitive and physical health.
3. Sustain Lifelong Cognitive Demand
Actively work to increase cognitive headroom and absolute capacity throughout your lifespan by continually learning new skills and engaging in cognitively stimulating activities, especially after retirement, to mitigate age-related decline. Early life education and late-life cognitive activity are the most protective factors.
4. Prioritize Quality Sleep
Optimize your sleep quality and avoid sleep deprivation, as suboptimal sleep significantly impairs memory retrieval and overall cognitive function. Improving sleep can help improve the speed at which you access stored memories.
5. Cultivate Social Connections
Prioritize social interaction, as it is critically important for long-term cognitive function and is often under-discussed as a protective factor against cognitive decline.
6. Avoid Multitasking, Focus Deeply
Avoid traditional work-based multitasking and constant task switching, as it leads to a significant loss of focus time (around 20 seconds to refocus) and does not provide the beneficial cognitive stimulus needed for skill development or functional brain change. Instead, dedicate focused attention to single tasks.
7. Choose Complex Cognitive Activities
When engaging in cognitive activities, select those that are complex, interactive, and involve problem-solving (e.g., learning a new language, playing 3D video games, or complex dance) over repetitive, predictable tasks like crossword puzzles, as they drive greater improvements in cognitive function.
8. Opt for Open-Skill Physical Activity
Incorporate open-skill physical activities (e.g., dancing, table tennis, badminton) into your routine, as they involve reacting to the environment and others, leading to greater improvements in cognitive abilities compared to closed-skill, repetitive exercises.
9. Manage Post-Injury Body Temperature
After a head injury, immediately move out of heat-stressed environments and actively cool down if needed, using external methods or Tylenol to regulate body temperature (ideally below 36.5°C) for 24-72 hours, as preventing fever is critical for better outcomes.
10. Prophylactic Creatine for TBI
For individuals at high risk of TBI, consider a creatine loading phase of 20 grams per day for one week to significantly increase brain creatine levels, which has demonstrated neuroprotective effects in animal models.
11. Daily Creatine for Brain Resilience
Maintain brain creatine levels by taking 5 grams of creatine monohydrate daily, as this can offer neuroprotection against TBI impacts, mitigate cognitive deficits from sleep deprivation, and may improve mood.
12. DHA Supplementation for TBI
Supplement with 2-6 grams of DHA daily to mitigate neuronal injury from concussive impacts, as studies in athletes showed a decrease in circulating neurofilament light, a marker of neuronal injury.
13. Choline Post-Head Impact
After a head impact, consider supplementing with 1-2 grams of citicoline (CDP choline) daily, as evidence suggests it may improve neuropsychological outcomes in TBI survivors.
14. Consider Chronic Hyperbaric Oxygen
In the chronic phase (weeks after injury), hyperbaric oxygen therapy (e.g., 30+ exposures over several months at 2 atmospheres, 1 hour, twice weekly) shows potential for improving cognitive function after concussion or TBI, though current evidence is mostly from uncontrolled studies.
15. Optimize Reaction Time
To improve reaction time and overall performance, consider specific training for reaction time, optimizing caffeine timing and dose, and potentially supplementing with tyrosine or creatine. This is particularly relevant for high-demand cognitive tasks.
6 Key Quotes
Once you've seen one case of Alzheimer's, you've seen one case of Alzheimer's.
Tommy Wood
If you're trying to remove amyloid, it's the same thing to try and treat Alzheimer's disease. It's the same thing as trying to revive somebody from the dead by removing their tombstone.
Tommy Wood
Medicine is the art of entertaining the patient while nature cures the disease.
Tommy Wood
The two most important protective ones were early in life education... and then late in life cognitive activity.
Tommy Wood
If you want an organ system to function in a specific way... you apply a relevant stressor that's... hormetic, and you give time to recover and adapt to it, and then you get an increased capacity later.
Tommy Wood
Traditional work based multitasking is probably the point where there's this biggest gap between perceived demand and the amount of beneficial cognitive stimulus you're actually getting.
Tommy Wood
1 Protocols
Short-Term Post-Concussion Management
Tommy Wood- Immediately remove the individual from a heat-stressed environment.
- Cool the individual down if needed, using external methods or Tylenol to manage body temperature.
- Focus on preventing fever by maintaining core body temperature at or below 36.5 degrees Celsius.
- Continue fever prevention and temperature management for 24 to 72 hours after the initial injury.