What Causes Symptoms in a Concussion

Concussions are often talked about as if they are one single injury with one single treatment. In reality, concussion symptoms can come from several different “symptom generators” throughout the body. That is why two people with the same diagnosis may have completely different symptoms — and why effective treatment requires an individualized approach.

A physical therapist trained in concussion rehabilitation can help identify which systems are contributing most to a patient’s symptoms and create a targeted treatment plan to address them.

1. Vestibulo-Ocular Dysfunction

The vestibular and visual systems help us maintain balance, stabilize our vision, and process movement. After a concussion, these systems can become disrupted, leading to symptoms such as dizziness, nausea, blurred vision, motion sensitivity, headaches, or difficulty focusing.

Treatment often involves vestibular and oculomotor rehabilitation exercises designed to gradually retrain the brain and nervous system. These may include:

• Eye tracking exercises

• Gaze stabilization drills

• Balance training

• Head movement coordination tasks

• Gradual exposure to visually stimulating environments

  
  

These exercises are progressed carefully based on symptom tolerance to improve the brain’s ability to process movement and visual information again.

2. Physiologic Dysfunction

Some individuals develop a physiologic intolerance after concussion, where the autonomic nervous system and cerebral blood flow regulation do not respond normally to exercise or activity. These patients may experience symptom flare-ups with physical exertion, changes in body position, elevated heart rates, or fatigue.

Research increasingly supports graded aerobic exercise as one of the most effective treatments for this presentation. Rather than complete rest, controlled sub-symptom threshold exercise helps restore normal nervous system regulation and improves recovery.

Treatment may include:

• Heart-rate based cardio programs

• Walking, biking, or treadmill exercise

• Gradual progression of intensity

• Monitoring symptom response and recovery patterns

  
  

Appropriately dosed exercise can help normalize autonomic function and improve overall recovery capacity.

3. Cervical Dysfunction

The neck is commonly involved in concussion injuries, as the force required to cause a whiplash injury is significantly less than the force necessary to cause a concussion. Sometimes you can even have a neck injury that presents like a concussion without ever having an injury to the brain. Cervical dysfunction can mimic or worsen concussion symptoms, including headaches, dizziness, visual disturbances, and balance problems.

Physical therapy treatment for cervical involvement may include:

• Manual therapy

• Soft tissue mobilization

• Joint mobilization

• Dry needling

• Deep neck flexor strengthening

• Postural retraining

• Mobility and stabilization exercises

  
  

Addressing cervical dysfunction is often a major missing piece in patients with persistent symptoms.

4. Anxiety and Nervous System Dysregulation

Concussions can place the nervous system into a heightened “fight-or-flight” state. Many patients become increasingly sensitive to normal stimuli, hyperaware of symptoms, and fearful of activity. This does not mean symptoms are “all in their head” — the nervous system itself can become dysregulated after injury.

Physical therapists can help patients regain confidence and calm the nervous system through:

• Education about concussion recovery

• Gradual exposure to movement and activity

• Breathing strategies

• Exercise

• Sleep and recovery guidance

• Techniques aimed at reducing sympathetic nervous system over-activity

  
  

One of the most important aspects of concussion rehab is helping patients understand that symptoms during rehabilitation are often expected and manageable, not necessarily signs of damage.

5. Gut, Hydration, and Recovery Factors

Nutrition, hydration, sleep, and general recovery habits can significantly influence concussion symptoms. Poor hydration, inconsistent eating patterns, poor diet, alcohol use, and inadequate sleep can all worsen headaches, fatigue, and cognitive symptoms.

Education in this area may include:

• Hydration strategies

• Consistent meal timing

• Appropriate protein and nutrient intake

• Sleep hygiene recommendations

• Reducing inflammatory lifestyle factors

  
  

While these factors may not “cause” concussion symptoms on their own, they can strongly influence the nervous system’s ability to recover.

The Bigger Picture

Successful concussion rehabilitation is rarely about one single exercise or one single treatment. Recovery often requires addressing multiple systems together while gradually returning the patient to normal life, exercise, school, work, and sport.

Every concussion is different. Identifying the primary symptom generators — and understanding how they interact — allows treatment to become more specific, targeted, and effective.

Treatments for these symptom generators often overlap with other healthcare providers, which is why a collaborative approach with neuro-opthamologists, psychiatrists, psychologists, dieticians, chiropractors, pediatricians, acupuncturists, massage therapists, and coaches is critical. With the right rehabilitation approach, most patients can make substantial improvements and safely return to the activities that matter most to them.