Post-Concussion Syndrome
What Is Post-Concussion Syndrome, and Why Do Symptoms Sometimes Linger?
Most people expect a concussion to be a short detour—an unpleasant week or two, then a return to baseline. Many people do improve within a couple of weeks, according to the CDC. (CDC)
But some don’t. When symptoms persist and start shaping daily life—work, school, sleep, mood, screens, crowds—clinicians may use terms like “post-concussion syndrome” or “persistent post-concussive symptoms.” Mayo Clinic notes these symptoms can last longer than three months and sometimes a year or more. (Mayo Clinic)
This post is a plain-English guide to what “persistent post-concussive symptoms” can look like, why they may linger, and what a reasonable medical follow-up often includes—without the false comfort of “your scan was normal, so you’re fine.”
Key Takeaways
Many people feel better within a couple of weeks after a mild TBI/concussion, but a meaningful minority have symptoms that last months or longer. (CDC)
Persistent symptoms are often multi-factorial (brain recovery plus vestibular, vision, neck, sleep, and mood contributors), so “wait and see” can stall when targeted evaluation is needed. (concussionsontario.org)
A normal CT or MRI does not rule out concussion-related symptoms; routine imaging is often about ruling out dangerous structural problems, not proving you’re symptom-free. (CDC)
Clear, function-based symptom reporting helps clinicians identify what to assess next and what treatment may fit. (Mayo Clinic)
If symptoms are worsening or you have danger signs, seek urgent medical care. (CDC)
Definitions You’ll Hear (and What They Actually Mean)
Concussion and mild traumatic brain injury (mTBI) are commonly used to describe the same clinical event: a change in brain function after a blow or jolt to the head or body. The “mild” label typically describes early measures (like brief or no loss of consciousness and initial exam findings), not how disruptive recovery may be. (CDC)
For symptoms that don’t resolve on the expected timetable, many modern resources use “persistent post-concussive symptoms.” Mayo Clinic describes these symptoms as lasting beyond the usual recovery window and often longer than three months. (Mayo Clinic)
For consistency in this post, I’ll use: persistent post-concussive symptoms.
What Persistent Post-Concussive Symptoms Usually Look Like
People rarely present with one neat symptom. More often, it’s a constellation—some physical, some cognitive, some emotional, often interacting with each other.
Common symptom clusters include:
Physical
Headaches or head pressure
Dizziness, imbalance, or motion sensitivity
Light/noise sensitivity
Nausea
Fatigue and reduced stamina (Mayo Clinic)
Thinking and memory
Trouble concentrating
Feeling slowed down or “foggy”
Memory problems, especially with new information (CDC)
Mood and sleep
Irritability
Anxiety or depression symptoms
Trouble falling asleep or staying asleep (Mayo Clinic)
A key point: these symptoms can be very real even when they are hard to “see” on routine tests.
Why Symptoms Sometimes Persist
There isn’t one single explanation that fits everyone. A more accurate frame is that concussion can disrupt multiple systems, and different people get stuck for different reasons. The Ontario Neurotrauma Foundation (ONF) guideline emphasizes that prolonged symptoms require careful assessment and management rather than assuming a single-cause story. (concussionsontario.org)
Common contributors clinicians consider include:
Ongoing neurologic recovery and symptom sensitivity
Symptoms can evolve over days and weeks, and recovery is not always linear. (CDC)Vestibular dysfunction (balance/motion system)
Dizziness, motion intolerance, and “busy environment” discomfort can reflect vestibular involvement that benefits from specific assessment. (concussionsontario.org)Vision/oculomotor problems
Eye teaming, focusing, and tracking issues can show up as headaches, reading difficulty, and screen intolerance—often missed unless screened for. (concussionsontario.org)Cervical (neck) injury contribution
A fall or collision can strain the neck. Cervicogenic headache and neck-driven dizziness can mimic “concussion that won’t go away” if the neck is not evaluated. (concussionsontario.org)Sleep and mood factors that amplify symptoms
Sleep disruption and mood symptoms can be part of the post-concussive picture and can also worsen pain, concentration, and fatigue. Treating these is not “blaming stress”—it’s addressing physiology and function. (Mayo Clinic)
What a Reasonable, Structured Workup Often Includes
If your symptoms are persisting or interfering with normal life, the next step is not self-diagnosis. It’s often a structured follow-up that looks for treatable drivers.
A thorough evaluation commonly includes:
A symptom inventory and timeline (what started when, what triggers symptoms, what makes them better/worse) (Mayo Clinic)
Neurologic exam and focused history
Vestibular assessment when dizziness/imbalance is present (concussionsontario.org)
Vision/oculomotor screening when reading and screens are difficult (concussionsontario.org)
Sleep assessment (because sleep quality often affects everything else) (CDC)
Neck evaluation, especially when headache and dizziness track with cervical pain or movement (concussionsontario.org)
Cognitive testing when clinically appropriate (not for everyone, but useful for some patients) (concussionsontario.org)
If you’re hearing, “Nothing is wrong; your MRI is normal,” it helps to understand the limitation: routine CT/MRI is often used to rule out acute bleeding or other dangerous structural injury. It does not “clear” you of functional symptoms. (CDC)
Myth vs. Reality
Myth: “If imaging is normal, the concussion is over.”
Reality: Normal imaging is common after concussion. It may rule out emergencies, but it does not automatically explain—or erase—ongoing symptoms. (CDC)
Myth: “If I have anxiety or depression symptoms, it wasn’t the concussion.”
Reality: Mood symptoms can be part of persistent post-concussive symptoms and can also magnify other symptoms like sleep problems, fatigue, and headaches. Addressing them is part of real care. (Mayo Clinic)
Myth: “Nothing can be done; I just have to wait it out.”
Reality: Persistent symptoms often involve specific, assessable contributors (vestibular, vision, neck, sleep). Identifying them can change the treatment plan. (concussionsontario.org)
Practical Guidance That Stays Health-First
If symptoms persist, focus on clarity over grit.
First, get re-evaluated if symptoms aren’t improving, are worsening, or are limiting work/school/life. The CDC advises contacting a healthcare provider when symptoms don’t go away or get worse. (CDC)
Second, describe impact in functional terms. Not “I feel off,” but “I can’t read for 15 minutes without a headache,” or “grocery stores trigger dizziness,” or “I’m sleeping in two-hour blocks.” This is not about “building a record.” It’s about giving clinicians usable information. (Mayo Clinic)
Third, do not let “normal MRI” end the conversation if you are still symptomatic. It’s a data point—not a verdict. (CDC)
When to Seek Urgent Care
After a head injury, seek emergency care if you have danger signs—especially if symptoms are getting worse. CDC discharge materials list red flags and emphasize getting help right away if concerning symptoms develop. (CDC)
FAQ
How long do concussion symptoms usually last?
Symptoms generally improve over time, and most people feel better within a couple of weeks—but some have symptoms for months or longer. (CDC)Is “post-concussion syndrome” a real diagnosis?
Many clinicians use the term, but many modern resources prefer “persistent post-concussive symptoms.” Either way, the concept is the same: symptoms can persist and deserve appropriate evaluation. (Mayo Clinic)Can I have persistent symptoms if I never lost consciousness?
Yes. Loss of consciousness is not required for a concussion diagnosis, and symptoms can appear immediately or later. (CDC)Why do screens and busy environments feel intolerable?
Light sensitivity, visual/oculomotor strain, and vestibular issues can make screens, scrolling, and complex environments more symptomatic for some people. (concussionsontario.org)Who typically evaluates persistent post-concussive symptoms?
Many people start with a primary care clinician and may be referred to a concussion clinic, neurology, rehabilitation medicine, vestibular therapy, or vision specialists depending on symptoms. The ONF guideline emphasizes coordinated assessment and targeted management for prolonged symptoms. (concussionsontario.org)
Disclaimer (General Information Only)
This post provides general educational information and is not medical advice or individualized legal advice. Reading this post (or contacting my office) does not create an attorney–client relationship. If you think you are experiencing a medical emergency, call 911 or go to the emergency room.
If you need legal advice, you should consult a licensed attorney in your state. If you do not already have a local attorney, you may contact us to request a referral to a lawyer in your area who handles traumatic brain injury matters.
Author: Chandler Crawford, esq.
