Man with top half of his head missing

MTBI 101: “Mild” Traumatic Brain Injury is NOT MILD!

In Brain Injury, MTBI 101, Research by Emerson Jane BrowneLeave a Comment

What a Mild Traumatic Brain Injury Really Feels Like!

Why is a MTBI called Mild?

The classification of traumatic brain injuriy as Mild, Moderate, and Severe was developed to allow rescue personnel to quickly communicate the severity of the initial physical trauma when a patient is being transported to the hospital. Used in emergent care the designations make sense. They are a way of letting the hospital know the level of immediate care the patient will need.

Mild traumatic brain injury is NOT Mild!

Though the terms Mild, Moderate, and Severe makes sense when used in emergency care, they have grown to be used universally as a diagnostic level of traumatic brain injuries.

That doesn’t work for a few reasons.

Initial brain injury symptoms do not represent the actual injury to the brain

The big reason that diagnosing a brain injury as  Mild is problematic is that the initial physical trauma classifications do not necessarily represent the actual damage to the brain. A brain can have very serious injury damage, but the person may not have lost consciousness nor had any amnesia. (See criteria table below)

The medical meaning of Mild is very different from the common definition of Mild

The other reason that calling a brain injury mild does not work is that the terminology – the word Mild – means something different in the medical community than it does to the general public.

In medicine, the classification terms Mild, Moderate, and Severe are used to describe levels of all sorts of medical problems. For example ailments such as Incontinence or Alzheimers are categorized as mild, moderate, and severe.

The medical definition of Mild always has specific parameters that define what the word means in relation to the ailment. At the bottom of this post is the criteria and a table that explains the definition of Mild Traumatic Brain Injury in medical terminology. Again, as you will see, that designation is all based solely on symptoms at the time of initial trauma.

Salsa Label with "Sweet Ed" on front

In general common use, the the term Mild  has the following meanings1

  • gentle and not easily provoked.
  • not keenly felt or seriously intended.
  • (of an illness or pain) not serious or dangerous.
  • (of weather) moderately warm, especially less cold than expected.
  • (of a medicine or cosmetic) acting gently and without causing harm.
  • (of food, drink, or tobacco) not sharp or strong in flavor.

Calling a Brain Injury “Mild” is confusing because the patient (and their family and friends) think of the common meaning; not the medical meaning.

Symptoms of a MTBI are NOT Mild!

Brain Injury Symptoms do not necessarily all appear at once. In fact, especially with a MTBI, symptoms occur over a period of weeks to many months.

Part of the reason for this is that brain injury is actually a complicated process; not a single incident. Yes the accident happened in a single instant. But it set in motion a huge cascade of injury and response in the body. Not all brain cell death and damage happens at the time of the accident. Fluid flow of nutrients and blood get altered, neurochemicals amounts change, electrical signals in the brain get interrupted, inflammation response begins . . . all of this affects the brain health. All of this is a response to the injury.

Often a MTBI survivor will not observe a symptom until they go to use that part of the brain and find it “missing”.

For instance, in your normal everyday life you might not need to do addition or division in your head for many months – especially when healing from an injury. Then one day when out to lunch with a couple of friends and the waiter hands you the tab for you to figure out your portion. Suddenly you realize you have no idea what 27+9 is or or even how to go about figuring it out. (Speaking from experience here! See the blog post Gone Missing.)

The internet abounds with stories of brain injury survivors who were told they were “fine” only to find they were anything but fine. There are stories of professional artists walking into their studios and having no idea what that thing with the bristles at the end of it is and no idea what to do with it (a paintbrush), etc. I used to walk away in the middle of talking with someone because I forgot I was in a conversation!

Symptoms of a TBI may be subtle but profound

brains control everything about us ; loss of sense of self

Now a caveat to all the above is that some Mild Traumatic Brain Injuries truly are mild. Sometimes, there is little damage done. Within weeks a person is fully back to normal. But that is not true of over 90% of MTBI injuries. And likely, if you are reading this article, it is not true for you or someone you know and care about.



Classification of TBI

The classification system is based on three factors – all of which relate to the condition of the patient immediately after the injury.

The Glasgow Coma Scale (GCS) is based on a 15 point scale measuring a patient’s motor response, verbal response and eye opening response.

A Mild Traumatic Brain Injury (MTBI) would have a Glasgow rating of 13 – 15.

Severity of traumatic brain injury2
Mild 13–15 <1
Moderate 9–12 >1 to <7
>30 min to
<24 hours
Severe 3–8 >7 days >24

Loss of Consciousness (LOC) is a measurement of the amount of time the person was unconscious.

For a MTBI classification a person can have anywhere from loss of consciousness at all, up to being unconscious for 30 minutes.

Post Traumatic Amnesia (PTA) is the length of time period you are unable to remember.

It is pretty common to not be able to remember an accident itself or to retain a clear memory of immediately after. For a brain injury to be considered mild the amnesia should be one day or less.


  1. Oxford English Dictionaries: <a href=”“>mild</a>
  2. Department of Defense and Department of Veterans Affairs (2008). “Traumatic Brain Injury Task Force”. (retrieved from Wikipedia: Traumatic Brian Injury Classification)
Emerson Jane Browne
I am Emerson Jane Browne. I write about Brains, Apps, & Productivity, and many other aspects of Life. I speak to TBI support groups, speak and teach workshops at tech, music, and writer conferences. I consult with organizations on strategic planning and building a strong community.