How do concussions affect the brain?

September 28, 2026

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5 min read

How Concussions Actually Affect the Brain

"Concussion, as you know, is an invisible injury," says Dr. Tina Shetty, former neurologist for the New York Giants. That invisibility is the core challenge: a concussion patient "physically often appear completely fine" while their brain is struggling with a functional disruption that no standard scan can detect. Shetty, who now runs a concussion clinic in New York and has written Healing the Brain, explains that concussions are not structural injuries like a bruise or bleed — they are connectivity injuries. The brain's complex network of regions that normally work together (frontal lobes for executive function, occipital lobes for vision and balance, temporal lobes for memory) becomes temporarily dysfunctional at the level of synapses and chemical signaling. This is why symptoms are so varied and non-specific: headache, dizziness, sensitivity to light, noise, and screens. And it is why the old advice to "cocoon" in a dark room has been abandoned in favor of active intervention.

The Metabolic Crisis Inside the Skull

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What you'll learn

1 (01:54) **Dr. Tina Shetty Introduced** - Former Giants neurologist and author of *Healing the Brain* joins to discuss concussion science and changing treatments.
2 (04:01) **The Evolution of Concussion Awareness and the CTE Question** - She reflects on the early 2000s when CTE links were first emerging, and explains why the new one-in-four NFL player statistic is hard to apply clinically.
3 (06:36) **How Pro Athletes Get Treated Differently** - The speed and team-based approach to concussion care in professional sports contrasts sharply with what the general public experiences.
4 (08:05) **The Limits of Scans and the New Blood Test** - Explains why standard imaging is normal for concussion and what the FDA-approved blood test actually detects.
5 (08:48) **What "Functional Injury" Actually Means** - A clear explanation of how the brain's network and chemistry go awry after a concussion.
6 (10:42) **You Don't Have to Hit Your Head** - The mechanics of concussion involve rotational acceleration-deceleration, including whiplash, and the neck is often ignored in treatment.
7 (11:41) **Why Symptoms Vary So Widely** - Because concussion is a connectivity injury, symptoms are non-specific and hard to localize to one brain region.

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Show Notes

Football season is upon us and a new study is making headlines. Researchers found that roughly 1 in 4 NFL players will develop CTE, a neurodegenerative disease, in their lifetime. While most of us are not professional athletes, concussions are still a relatively common injury. Millions of Americans get concussions each year, but the exact number is hard to pin down because many people don’t seek treatment.

So what are we learning about how concussions affect the brain? And how are the best practices for treatment changing? To answer those questions and more Flora sits down with Teena Shetty, a former neurologist for the New York Giants and author of the new book “Healing the Brain.”

Guest:

Dr. Teena Shetty is a former neurologist for the New York Giants and founder of the Teena Shetty MD Concussion Clinic. She is also an associate professor of clinical neurology at Weill Cornell Medical College and author of “Healing the Brain.”

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