Dr. Ryan Cedermark

08/11/2025

In functional neurology, the prefrontal cortex (PFC)–amygdala relationship is one of the core regulatory loops that determines how a patient responds to the world, learns new skills, and recovers from injury.

Here’s the breakdown:

1. The Prefrontal Cortex (PFC)–Amygdala Circuit

Amygdala: Rapid emotional and threat detector — processes fear, stress, and emotional salience before conscious thought.

PFC: Executive control center — plans, inhibits, regulates emotion, and applies logic.

Healthy Relationship: The PFC exerts top-down regulation over the amygdala, helping you pause, assess, and respond instead of react.

Dysfunctional Relationship: If the amygdala is hyperactive (as in chronic stress, TBI, or neurodevelopmental disorders), its signals can overwhelm the PFC, impairing decision-making, attention, and emotional control.

2. In Neurodevelopment

In children, the PFC is still maturing (well into the mid-20s), so emotional regulation relies more heavily on subcortical structures like the amygdala.

Early stress or adverse experiences can strengthen amygdala reactivity while weakening PFC control circuits.

Therapies that train sustained attention, working memory, and inhibition help wire stronger PFC-amygdala connections.

3. In Brain Injury

TBIs, especially frontal lobe injuries, can weaken inhibitory control over the amygdala, leading to impulsivity, irritability, and emotional lability.

Functional neurology therapy often pairs executive function tasks with autonomic calming strategies (e.g., vagus nerve stimulation, breath work) to help re-establish regulation.

4. In Chronic Stress

Long-term stress → high cortisol → structural changes:

PFC volume & connectivity can shrink

Amygdala becomes more excitable

This creates a feed-forward loop where stress further reduces regulation, increasing reactivity.

Therapy focuses on breaking the loop via neuroplastic training + autonomic balance work.

https://www.sciencedirect.com/science/article/pii/S2352289514000101

08/05/2025

Using photobiomodulation (PBM) on the cerebellum in a functional neurology clinic can be a strategic intervention to enhance neuroplasticity, metabolic function, and recovery in patients with neurological disorders. Here’s a breakdown of the clinical reasoning:

1. The Cerebellum’s Role in Neurological Function

Traditionally associated with motor coordination and balance.

Increasingly recognized for its role in:
• Cognition and attention
• Emotional regulation
• Eye movements and postural control
• Autonomic integration
• Vestibular processing

Damage or dysfunction in the cerebellum can affect all of the above, especially in conditions like concussion, developmental disorders, dysautonomia, and neurodegenerative diseases.

2. Mechanisms of PBM on the Cerebellum

Photobiomodulation (typically using red or near-infrared light in the 660–1100 nm range) can:

Enhance mitochondrial activity (cytochrome c oxidase activation)

Increase ATP production to fuel neural repair and synaptic activity

Reduce oxidative stress and inflammation

Improve local blood flow and oxygenation

Stimulate neurogenesis and synaptogenesis

These effects may be particularly valuable in hypoactive, inflamed, or degenerating cerebellar regions.

3. Clinical Applications in Functional Neurology

PBM to the cerebellum may benefit patients with:

Concussion or mild traumatic brain injury (mTBI)
Cerebellar hypoplasia or ataxia
Balance and coordination deficits
Autonomic dysfunction (via cerebellar-autonomic connections)
Developmental delays (e.g., autism spectrum)
Vestibular dysfunction and oculomotor issues
Cognitive impairments (via cerebello-thalamo-cortical circuits)

07/09/2025

How Can the RAS Improve Your Life?

1. Sharpening Your Focus

Your RAS helps you notice more of what aligns with your goals. For example, if you’re focused on improving your health, you might start noticing fitness articles, healthy food options, or people around you who are also health-minded.

2. Reinforcing Positive Change

When you consciously set intentions (like “I am healing” or “I can find solutions”), your RAS begins tuning into experiences and cues that support those beliefs. It acts as a feedback loop between your thoughts and your environment.

3. Overcoming Limiting Beliefs

If you constantly tell yourself you’re stuck, your RAS will filter the world to confirm that belief. But if you reframe your thoughts (“There’s always a way forward”), your brain starts filtering for possibility instead of limitation.

4. Enhancing Neuroplasticity

By consistently focusing on growth, healing, or learning, you activate your RAS to reinforce those pathways — literally helping rewire your brain over time.

How to Activate Your RAS Intentionally

✅Set Clear Goals – Write down or visualize what you want. Your RAS needs something specific to filter for.

✅Use Positive Affirmations – Repetition helps tell your RAS what matters.

✅Practice Gratitude – The more you look for the good, the more your brain shows it to you.

✅Control Your Inputs – Surround yourself with people, environments, and content that support the changes you want.

Bottom line:

Your Reticular Activating System is always working. When you train your mind to focus on what you want — rather than what you fear — your brain begins showing you the path forward. That’s powerful brain science in action.

07/01/2025

How Balance Training, Walking, and Pickleball Improve Functional Neurology Outcomes After Brain Injury or Stroke

1. Balance Training (Standing on Whole-Body Vibration)

Balance is the foundation of functional recovery. Standing on vibration platforms stimulates proprioceptive input from the feet and spine, directly activating the cerebellum, vestibular nuclei, and somatosensory cortex.

✅Enhances posture and midline control
✅Primes the brain for neuroplastic change
✅Improves vestibular function and sensory integration

Vibration also boosts muscle spindle sensitivity and motor readiness, helping patients with stroke or TBI regain foundational control and reduce fall risk.

2. Walking

Once basic balance is supported, walking reintroduces rhythmic, cross-pattern movement that stimulates interhemispheric communication and neurovascular coupling.

✅Improves frontal lobe activation and gait control
✅Boosts BDNF and neurogenesis in motor pathways
✅Re-engages coordination between the cerebellum, brainstem, and cortex

Walking is a natural and powerful tool to support recovery, especially when paired with dual-task cognitive or sensory challenges.

3. Pickleball

Pickleball combines all of the above…balance, dynamic movement, cognitive processing, and coordination…in an engaging, real-world setting.

✅Activates frontal, parietal, cerebellar, and motor networks
✅Enhances reaction time, gaze stability, and timing
✅Promotes social interaction, motivation, and autonomic regulation

Pickleball is an ideal late-stage rehab tool to reinforce integration of brain networks and improve functional outcomes in real-life scenarios.

Clinical Application Tip:
👉 Progressive layering is key—start with static balance, move to locomotion, then introduce dynamic coordination.
👉 Use vibration or neuromodulation (e.g., tVNS, PBM) before walking or sport to enhance plasticity.

05/22/2025

Photobiomodulation—using red or near-infrared light (600–1100 nm)—stimulates mitochondria and improves cellular energy production, particularly in neurons. This directly impacts neuroplastic potential.

🧠 Key Mechanisms:

1. ↑ ATP Production

PBM activates cytochrome c oxidase in mitochondria → increases ATP synthesis.

More ATP = more energy for synaptic transmission, axonal growth, and remyelination.

2. ↑ BDNF and Neurotrophins

PBM stimulates the expression of BDNF, NGF, and other growth factors.

These promote synaptogenesis, dendritic sprouting, and neuronal survival—all core to strengthening neural circuits.

3. ↓ Inflammation and Oxidative Stress

Reduces levels of pro-inflammatory cytokines (e.g., TNF-α, IL-1β).

Increases antioxidant enzymes (e.g., SOD, catalase), creating a neuroprotective environment ideal for plasticity.

4. Enhances Cerebral Blood Flow

PBM causes vasodilation and improves oxygen delivery to targeted brain regions.

Better perfusion supports neuronal metabolism and functional recovery.

5. Modulates Brain Oscillations

Studies show PBM can influence gamma and alpha band activity in EEG.

This reflects changes in network synchronization, especially in the prefrontal cortex and default mode network, related to cognitive control and recovery.

05/19/2025

Walking with a weighted vest can enhance neuroplasticity by increasing proprioceptive input, vestibular engagement, and sensorimotor integration—all of which stimulate brain regions critical for movement coordination, balance, and body awareness.

Neuroplasticity Reasons to Begin Walking with a Weighted Vest:

1. Enhanced Proprioceptive Feedback

The added weight increases stimulation of joint and muscle receptors, which boosts sensory input to the somatosensory cortex and cerebellum. This sensory-rich environment supports plastic changes in areas responsible for motor control and balance.

2. Improved Vestibular-Cerebellar Integration

Walking under load subtly challenges balance and gait stability, increasing demands on the vestibular system and cerebellar processing, both of which are plastic and trainable systems involved in postural control.

3. Cortical Engagement via Load Compensation

Carrying weight recruits additional neural circuits in the motor cortex, premotor areas, and supplementary motor area to coordinate the increased physical demand, promoting corticospinal plasticity.

4. Stimulates Default Mode Network Disruption

The physical challenge of walking with a vest can help shift brain activity away from the default mode network (associated with passive states) toward task-positive networks, improving attention, body awareness, and cognitive-motor coupling.

5. Supports Gait Rehabilitation and Pattern Reinforcement

For individuals recovering from brain injury or neurological dysfunction, weighted walking reinforces central pattern generators (CPGs) in the spinal cord and brainstem, especially when paired with neuromodulation strategies.

6. Activates Neurotrophic Factors

The physical exertion from weighted walking increases production of brain-derived neurotrophic factor (BDNF) and IGF-1, which support synaptic growth, learning, and adaptation.

We have licensed chiropractors in Atlanta, Georgia, passionate about helping those suffering where other healthcare options have failed.

05/06/2025

What a great group!

I have wanted to do this class in person for a long time and I had an absolute blast teaching and meeting new, cool people.

Thank you to everyone who traveled in for this from all over (Canada, California, Texas, Oklahoma, Ohio, Missouri, Arizona, Florida, Tennessee, Virginia, Iowa, Chicago, Massachusetts, North Carolina and of course Georgia) it truly means a lot to me.

I took a lot of great things away from the weekend from everyone who attended so I hope you did too!

Big thank you to our sponsors:








Stay Nerdy🤓😎

04/22/2025

Here is a slide from my upcoming workshop next weekend, May 3 and 4.

On Saturday, I am discussing protocols for brainstem stimulation to improve parasympathetic function in the body.

The ear is densely innervated by the vagus nerve and serves as a conduit for improving neuroplasticity.

Register: https://iafnr.mykajabi.com/offers/yRBFueTY/checkout

04/22/2025

Hi Everyone!

I received an email updated regarding pre-order for a new vagus nerve headphone device from Hoolest Performance Technologies

I have used the VeRelief in the past but have been wanting to try these for some time now. I placed an order and the device should be shipped in the summer but wanted to share a link to purchase here if you are interested.

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The device itself is currently discounted to $549 from $800 which, for a wearable vagus nerve stimulator that you can pair with sound is a very reasonable price in my opinion.

My brainchat code got leaked so if you would like to save extra, you can enter the code "cedermark10" at checkout for an extra discount.

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04/14/2025

Got some tough news this week about a very close friend's brother. He suffered a spinal cord injury while playing with his children. Please keep them in your thoughts and prayers!

On April 6th, 2025, my brother, Seth, suffered a devastating cervical spi… Robyn Kurpiel needs your support for Support Seth's Spinal Injury Recovery Marathon

04/09/2025

The difference between structural and functional neuroplasticity comes down to what changes in the brain and how those changes support learning, recovery, or adaptation:

Structural Neuroplasticity
✅What it is: Physical changes in the brain’s structure.

Examples:
✅Growth of new neurons (neurogenesis).
✅Formation of new synapses (synaptogenesis).
Strengthening or pruning of dendritic branches.
✅Changes in white matter (e.g. myelination of axons).

When it happens: During learning, after injury, or in response to long-term environmental changes.

Outcome: A more permanent rewiring of the brain’s architecture to support long-term adaptation or recovery.

Functional Neuroplasticity

What it is: Changes in how existing neurons and networks function.

Examples:
✅Shifting responsibilities from one brain area to another (e.g., after stroke).
✅Reorganization of cortical maps (like in phantom limb syndrome).
✅Increased efficiency or responsiveness of neural pathways.

When it happens: Rapidly in response to short-term demands or damage.

Outcome: More flexible, immediate changes that support continued functioning or compensation.

In a nutshell:
✅Structural = rewiring the hardware.
✅Functional = reprogramming the software.

They often work together—for example, functional changes can drive structural remodeling over time if the demand persists.

04/09/2025

Here is a slide from my upcoming weekend in May!

I will be teaching basic principles in functional neurology rehabilitation…the eyes being a big part it!

Eye movement therapy is a core component of functional neurology rehab. It’s grounded in the principle that specific eye movements activate and influence different regions of the brain, especially the brainstem, cerebellum, and cortical areas involved in spatial awareness, attention, and motor control.

Here are some key aspects of how it’s used:

👀Saccades (quick, simultaneous movements of both eyes in the same direction) can be used to assess and rehabilitate frontal lobe and brainstem function.

👀Smooth pursuit exercises (slow tracking of a moving object) target cerebellar and parietal lobe activity.

👀Vestibulo-ocular reflex (VOR) training improves coordination between the vestibular system and eye movements—key for balance and spatial orientation.

👀Convergence and divergence therapy is used for midbrain and frontal integration, often helpful in post-concussion care.

Functional neurologists often tailor eye movement therapies based on asymmetries in function—so rightward or leftward eye movements might be emphasized depending on which hemisphere needs activation.

Join me in May to learn a ton more!!

https://iafnr.mykajabi.com/offers/yRBFueTY/checkout