Better Brain Fitness with Drs. Josh Turknett and Tommy Wood

Neuroscientist Dr. Sarah McKay has spent more than a decade tracking what the science actually says about women's brains, from pregnancy through menopause. She's the author of The Women's Brain Book, Baby Brain, and Brain Health For Dummies. We talk about why the grey matter changes of pregnancy look like a reorganization that prepares a mother to care for her baby, why so many women report "baby brain" when lab tests pick up very little, what menopause hormone therapy has and hasn't been shown to do for the brain, and how to talk honestly about uncertainty when social media rewards confident claims.


Links & Resources:
Dr. Sarah McKay: drsarahmckay.com
Sarah's books (The Women's Brain Book, Baby Brain, Brain Health For Dummies): drsarahmckay.com/books
Hoekzema et al. (2017), "Pregnancy leads to long-lasting changes in human brain structure," Nature Neuroscience
To submit a question for us to answer on the podcast, go to brainjo.academy/question.

To subscribe to the free Better Brain Fitness newsletter, join us when we record live, and get our Guide and Checklist to essential blood tests and nutrients, go to: betterbrain.fitness.
To learn more about how you can boost brain fitness with neuroscience-based musical instruction, head to brainjo.academy. 
Intro and Outro music composed and produced by Julienne Ellen.

Your brain runs on roughly 400 miles of blood vessels, and most of them are too small to see on a standard scan. Vascular neurologist Dr. Jason Hinman of UCLA studies how those tiny vessels keep the brain's white matter healthy, and why vascular injury shows up alongside Alzheimer's disease in at least half of patients.

We talk about: 
new blood tests and MRI techniques that can pick up vascular changes years before today's scans do,
the subtle signs clinicians tend to miss, and
the most practical levers people have


Links & Resources:
The Hinman Lab at UCLA: hinmanlabucla.org/
To submit a question for us to answer on the podcast, go to brainjo.academy/question.

To subscribe to the free Better Brain Fitness newsletter, join us when we record live, and get our Guide and Checklist to essential blood tests and nutrients, go to: betterbrain.fitness.
Better Brain Fitness on Apple Podcasts: https://podcasts.apple.com/us/podcast/better-brain-fitness-a-brainjo-production/id1441139485
Better Brain Fitness on Spotify: https://open.spotify.com/show/2bTSpFGJ38QUx25HW62fC7
Intro and Outro music composed and produced by Julienne Ellen.

To grab your copy of the book, head to GeniusAndImpostor.com.

To submit a question for us to answer on the podcast, go to brainjo.academy/question.

To subscribe to the free Better Brain Fitness newsletter, join us when we record live, and get our Guide and Checklist to essential blood tests and nutrients, go to: betterbrain.fitness.
To learn more about how you can boost brain fitness with neuroscience-based musical instruction, head to brainjo.academy. 
Intro and Outro music composed and produced by Julienne Ellen.

Henry Mahncke is the CEO of Posit Science and the creator of BrainHQ, the most researched brain training platform in the world. A neuroscientist who did his PhD with Michael Merzenich, considered the father of adult brain plasticity, Henry has spent two decades translating brain plasticity science into tools that actually improve brain health. In this conversation, we dig into why most brain training criticism misses the point, what the largest clinical trials really show, and why the future of brain health looks a lot like the evolution of physical fitness.
In this episode:
00:00 — Introduction and Henry's background (PhD with Merzenich at UCSF, McKinsey, founding Posit Science)
07:00 — Brain training vs. cognitive training: why the distinction matters
09:00 — Brain plasticity as the driver of brain health, and why cognitive reserve is really just brain health
13:00 — Maladaptive brain plasticity: how aging actively degrades information processing through negative plasticity
18:00 — How BrainHQ exercises are designed: adaptive speed and accuracy training from psychophysics
24:00 — The transfer and generalization debate: does brain training improve real-world function?
28:00 — Clinical trial evidence: the Mayo/USC RCT, the ACTIVE study, and 300+ published papers
34:00 — The pharmaceutical analogy: why asking "does brain training work?" is the wrong question
37:00 — Who is brain training for? From post-concussive disorder to Tom Brady
44:00 — Brain training as physical exercise: the case for everyone at every age
46:00 — Real-world brain plasticity activities: racquet sports, musical instruments, foreign languages
51:00 — Josh's Brainjo origin story and what music training does for the brain
55:00 — The loss of skill learning in modern life and education
58:00 — The "dark ages" of brain health and where the field is headed
To submit a question for us to answer on the podcast, go to brainjo.academy/question.

To subscribe to the free Better Brain Fitness newsletter, join us when we record live, and get our Guide and Checklist to essential blood tests and nutrients, go to: betterbrain.fitness.
 Click here to order Dr. Wood's book, "The Stimulated Mind."
 Click here to pre-order Dr. Turknett's upcoming book, "The Genius and the Impostor"
Intro and Outro music composed and produced by Julienne Ellen.

Can a shingles vaccine cut your dementia risk by 20%?

A series of landmark studies — published in Nature, Cell, and JAMA — say yes.

In this episode, Tommy unpacks the research: how natural experiments in four countries produced one of the most compelling signals in dementia prevention, what might explain the effect beyond infection prevention, and what it means for your own vaccination decisions.
In this episode:
00:00 — Introduction
00:52 — The new data on shingles vaccination and Alzheimer's risk
01:48 — The Stanford group and their regression discontinuity methodology
03:15 — How birthday-based eligibility creates a natural experiment (Wales, Canada, Australia)
05:28 — Results: a ~20% reduction in dementia diagnoses across all countries
06:52 — The Cell paper follow-up: benefits at every disease stage (unimpaired → MCI → dementia)
07:55 — Shingrix vs. Zostavax: the US natural experiment and a potentially larger effect
09:08 — Why does it work? Preventing illness, avoiding bed rest and disuse, immunomodulation
11:29 — Neuroinflammation and possible immune system "tuning" effects
12:27 — The sex difference: greater benefit in women in most (but not all) studies
15:52 — Summary of the evidence and what it means for dementia prevention strategy
17:36 — Josh's take: number needed to treat analysis
19:15 — Heterogeneous pathways to dementia and why vaccination fits the toolkit
21:13 — Practical advice: when to get vaccinated, repeat dosing, and personal risk assessment
25:36 — Wrap-up and how to submit questions
Links & Resources:
Shingles vaccine and dementia studies: Nature (Wales, 2025), Cell (Wales follow-up), JAMA/Lancet (Canada, Australia, US)
Flu vaccine and dementia: Neurology (2026)
Tommy's book: The Stimulated Mind
To submit a question for us to answer on the podcast, go to brainjo.academy/question.

To subscribe to the free Better Brain Fitness newsletter, join us when we record live, and get our Guide and Checklist to essential blood tests and nutrients, go to: betterbrain.fitness.
To learn more about how you can boost brain fitness with neuroscience-based musical instruction, head to brainjo.academy. 
Intro and Outro music composed and produced by Julienne Ellen.