Signs of a Mild Concussion: What You Need to Know

A mild traumatic brain injury (mTBI), commonly referred to as a concussion, occurs when a bump, blow, or jolt to the head causes the brain to move rapidly back and forth inside the skull. While often termed "mild" because it is usually not life-threatening, the functional disruptions can be significant (Polinder et al., 2018).

Recognizing the symptoms early is essential for proper recovery. Below are the primary signs of a mild concussion, categorized by how they affect your body and mind.

1. Physical Symptoms: Headaches and Dizziness

Headaches are the most common symptom reported after a concussion (McInnes et al., 2017). They may feel like a constant pressure or a sharp, throbbing sensation.

Dizziness and balance issues are also frequent indicators (Polinder et al., 2018). You might feel:

Unsteady on your feet.
A "spinning" sensation (vertigo).
Lightheadedness when standing up quickly.

2. Sensory Sensitivity: Light and Sound

A concussed brain often struggles to process environmental stimuli. Many individuals experience photophobia (sensitivity to light) and phonophobia (sensitivity to sound). Common experiences include:

Finding normal indoor lighting or sunlight painfully bright.
Feeling overwhelmed or irritated by background noise, such as a television or crowded room.

3. Emotional and Mood Changes

A concussion can disrupt the chemical balance of the brain, leading to sudden shifts in temperament (McInnes et al., 2017). Watch for:

Increased Irritability: Getting "snappy" or frustrated more easily than usual.
Anxiety or Depression: Feeling unusually nervous, sad, or "emotionally labile" (unpredictable mood swings).

4. Sleep Disturbances

Changes in sleep patterns are a hallmark of mTBI (Polinder et al., 2018). These can manifest in two opposite ways:

Hypersomnia: Sleeping much more than usual or feeling constantly drowsy.
Insomnia: Having trouble falling asleep or staying asleep despite feeling exhausted.

5. Neck Tightness and Physical Strain

Because head injuries often involve rapid movement (like whiplash), neck tightness and pain are frequent comorbidities. This tension can exacerbate headaches and make it difficult to focus or move comfortably.

Summary Table: Concussion Signs at a Glance

Category	Common Signs
Physical	Persistent headaches, dizziness, nausea, neck stiffness.
Sensory	Blurred vision, sensitivity to light/sound, ringing in ears.
Cognitive	Feeling "foggy," slowed reaction times, memory issues.
Emotional	Irritability, sadness, heightened anxiety.
Sleep	Sleeping too much, trouble sleeping, extreme fatigue.

When to See a Doctor

If you or a loved one experiences a head injury, it is vital to monitor symptoms for at least 48 to 72 hours. While most concussions resolve with rest, persistent or worsening symptoms should be evaluated by a healthcare professional to prevent long-term complications (McInnes et al., 2017).

References

Polinder, S., Cnossen, M. C., Real, R. G. L., Covic, A., Gorbunova, A., Voormolen, D. C., Master, C. L., Haagsma, J. A., Diaz-Arrastia, R., & von Steinbuechel, N. (2018). A Multidimensional Approach to Post-concussion Symptoms in Mild Traumatic Brain Injury. Frontiers in Neurology, 9. https://doi.org/10.3389/fneur.2018.01113

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McInnes, K., Friesen, C. L., MacKenzie, D. E., Westwood, D. A., & Boe, S. G. (2017). Mild Traumatic Brain Injury (mTBI) and chronic cognitive impairment: A scoping review. PLOS ONE, 12(4), e0174847. https://doi.org/10.1371/journal.pone.0174847

Cited by: 742