There are several different types of TBI. Traumatic brain injury can be classified as mild, moderate or severe. Let’s take a closer look at mild TBI, which is often referred to as mTBI or concussion. With a mild traumatic brain injury there is sometimes a brief loss of consciousness or a feeling of “having your bell rung” after a head trauma. Lab tests and scans are usually normal; however, personality, memory, physical abilities, or other functions can be affected.
Mild TBI or concussion can cause a loss of consciousness, called LOC, loss of memory, or confusion. Thinking may become slow and disorganized, memory can become unreliable, and concentration often becomes difficult. The injury blocks the pathways normally used by the brain to send messages. When this trauma occurs, the brain is not able to continue normal function and so it shuts down.
This “shut down” can be either complete, which causes unconsciousness, or partial, which has been described as a “dazed” feeling. Keep in mind that a loss of consciousness is not required for an injury to be considered a concussion, or mild TBI.
Specific factors for diagnosing mild TBI include:
- Loss of consciousness, if any, lasting for less than 30 minutes
- Memory loss after the traumatic event, called post-traumatic amnesia or PTA, that lasts for less than 24 hours, and
- A Glasgow Coma Score of 13 – 15. This score measures a person’s eye opening abilities, verbal responses and motor responses. It is rarely used in diagnosing mild traumatic brain injury but is more commonly used in moderate to severe cases.
In most mild TBI cases, the patient will recover completely. In a small number of cases, the symptoms can last a long time and cause permanent changes to the patient’s life, for example in areas such as personality and memory.