Editor's note: This is part two of a multi-part series.

Not all brain injuries are the same. The event that causes the injury can also be very different for everyone from the event itself, to the amount of force received that impacts the head, and the areas of the brain that is affected.

There are two types of brain injuries: traumatic and acquired.

A traumatic brain injury can be caused by one of several events.

A concussion is caused by a direct blow to the head or violent excessive shaking of the head, such as a whiplash type of injury. Both open and closed head injuries can produce a concussion.

A concussion results when the brain receives an impact or a sudden change in the momentum or movement that can cause the blood vessels in the brain to stretch and cranial nerves are damaged.

A person does not always lose consciousness. They may remain conscious but feel dazed or groggy.

A concussion does not always show up on diagnostic image tests, such as a CAT scan. A skull fracture, brain bleeding or swelling may or may not be present and it may take months to even years for a concussion to heal.

A contusion is a bruise or bleeding on the brain. It results from a direct impact to the head and large contusions may need to be surgically removed.

A coup-contrecoup injury is a contusion at the site of impact and on the complete opposite side of the brain.

It occurs when the force of the impact is not only great enough to cause a contusion at the site of impact, but also move the brain causing it to slam into the opposite side of the skull causing an additional contusion.

A diffuse axonal injury can be caused by shaking or strong rotation of the head. Examples of this are shaken baby syndrome or a car accident.

This injury occurs when the unmoving brain lags behind the movement of the skull causing nerve tissue to tear throughout the brain disrupting communication and chemical processes.

This often results in brain damage, coma, even death.

A penetrating injury to the brain occurs from an impact that forces an object into the brain. Examples of this are a bullet, knife or other sharp objects that forces hair, skin, bone or bone fragments into the brain.

Objects traveling through the brain can ricochet and cause a wider area of damage.

A through-and-through injury occurs when an object enters the brain, travels through the brain and exits the skull.

An acquired brain injury is damage to the brain that is received after birth from events like strokes, tumors, anoxia, hypoxia, toxins, infections, degenerative disease, near drowning or other conditions not caused by an external force.

An anoxic brain injury occurs when the brain does not receive any oxygen and the brain cells begin to die.

A hypoxic brain injury occurs when the brain receives some, but not enough oxygen.

With each diagnosed brain injury comes the severity, or level, of the brain injury.

A mild traumatic brain injury occurs when there has been a brief loss of consciousness lasting a few seconds or minutes, but a loss of consciousness if not required.

A person may also feel dazed or confused and brain scans may appear normal.

A mild traumatic brain injury is diagnosed only when there is a change in mental status at the time of the injury.

This change indicates the person’s brain functioning has been altered, resulting in a concussion.

A moderate traumatic brain injury usually results from a non-penetrating blow to the head and/or a violent shaking of the head resulting in a loss of consciousness from a few minutes to several hours.

The individual who suffered the brain injury may also exhibit physical, cognitive and/or behavioral impairments that last for a few months to permanent.

Severe brain injuries usually result from a crushing blow or a penetrating wound to the head.

This is the most life-threatening type of brain injury that often, but not always, results in open head injuries or one that has been crushed.

Treatment of severe brain injuries typically requires prolonged hospitalization and extensive rehabilitation that is often incomplete.

Rarely does an individual who suffers a severe brain injury return to pre-injury status.

Mary Ann Derie, an RN Case and Program Manager at the Fort Polk TBI Clinic said that anyone who has suffered a head injury, no matter how slight, should be screened for a TBI.

If a mild TBI is suspected or diagnosed the best course of action is to rest. It is imperative for the first 24-48 hours to avoid looking at a computer screen, tablet and a cell phone. Caffeine should also be avoided.

Stimuli should be avoided as much as possible to give the brain time to recover and heal itself.

The TBI Clinic on Fort Polk opened in 2009 and they are using a new tool that is pivotal in early diagnosis of mild TBIs.

The BrainScope is a brain injury assessment device that can detect brain bleeds or identify other brain injuries that need further diagnostic testing.

It is primarily focused on diagnosing TBI in military injuries, sports and emergency or urgent care. It must be used within three days of the event causing the suspected TBI. The BrainScope is a handheld device that connects to a mobile phone and administers a point-of-care EEG.

Results are immediate and a patient can begin treatment sooner.

Some common signs and symptoms of TBI are:

Headaches Sleep disturbances Dizziness Balance problems Nausea and/or vomiting Fatigue Light sensitivity Visual disturbances Ringing in the ears Poor concentration Slow thinking Memory problems Anxiety Depression Irritability Mood swings

Individuals can suffer all or some of these symptoms.

If you have or think you have suffered a concussion or traumatic brain injury see a doctor.

Even if it turns out to be that it was nothing, it’s better to be safe than sorry. Repeated concussions, age and failure to give the brain time to recover leads to more damage over time. Possibly even permanent damage.