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What Causes Traumatic Brain Injury?

Traumatic Brain Injury or TBI is caused by an external physical force to the head that impacts on the brain. The head might be struck by an object, impact against a solid surface or be penetrated by a projectile. Brain injury severity can vary from mild to severe, and individuals can experience a range of symptoms depending on severity.

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Causes of Traumatic Brain Injury

The human brain consists of billions of interconnected neurons that act as the master control centre for the body and the mind. The brain is a fragile organ and it is protected by being completely encased in the skull. The brain obtains additional protection by being wrapped in fluid filled membranes that absorb forces that impact on the skull. Still, in spite of this protection, the injury to the head can be sufficient enough to overwhelm the brain’s protective mechanisms, and a brain injury will occur. Common causes of TBI include road traffic crashes, falls, sporting injuries, assault and family violence.

Types of Traumatic Brain Injury

In moderate to severe traumatic brain injuries, a distinction is made between ‘closed head injuries’ and ‘open head injuries’. A closed head injury is one where the skull and the brain have not been penetrated. An example might be an individual who strikes his or her head during a motor vehicle crash. The sudden changes in velocity will cause the brain to move violently within the skull, colliding with the bony structures inside the skull. This, in turn, can lead to bruising of the brain tissue, damage to neurons, as well as damage to the blood vessels that supply the brain.

An open head injury is one where the skull and brain have been penetrated. A gunshot wound, or a wound caused by projectiles from a blast, are examples of open head injuries.  Stroke is not typically referred to as a traumatic brain injury, but rather an acquired brain injury due to the absence of external traumatic force on the brain.


Severity of Traumatic Brain Injury

Brain injuries are often graded along a continuum of severity ranging from mild to moderate and severe. A number of factors will determine the severity of a TBI and the medical team will properly assess the level of injury severity. The severity of a brain injury can be evaluated using a number of different tools and indicators. Information that will be considered in evaluating the severity of a brain injury will include the duration of loss of consciousness, the depth of coma, the length of time new memories are not being laid down (termed “post traumatic amnesia”), the extent of memory loss and the results of brain scans.

Some important factors in determining severity will include the seriousness of the initial injury to the head, the part of the brain affected by the injury, the nature of complications arising from the injury (e.g., swelling, bleeding), and the type of treatment that was made available to the injured individual.


The Symptoms of Traumatic Brain Injury

After a moderate to severe traumatic brain injury, the person and their family may not fully understand the range or extent of symptoms. Brain injuries are complex injuries and there is no single profile or treatment. The health professionals and medical team will provide important information about the individuals’ brain injury and their specific symptoms. All brain injuries are different. Generally, the symptoms of TBI can fall into three broad classes: physical symptoms, sensory and, cognitive symptoms and behavioural symptoms.

Physical Symptoms

There are a number of physical symptoms that might be experienced following a TBI.  Some of these might include loss of consciousness, feelings of disorientation, nausea or vomiting, headaches, dizziness and loss of balance. In more severe cases, additional symptoms might include coma, slurred speech, convulsions or seizures, loss of coordination, generalised weakness and fatigue, pupils that do not contract when exposed to light, and fluids draining from the nose or ears.


Sensory Symptoms

TBI can also affect the sense organs. Sensory symptoms might include blurred vision, ringing in the ears, changes in the ability to taste and changes in the ability to smell.

Cognitive and Behavioural Symptoms

Traumatic brain injury can affect the person’s ability to process information and cause them to behave in different ways compared to before the injury. Memory and concentration difficulties are common following TBI. In more severe cases, there might be signs of confusion. The person with a TBI might also experience changes in mood. These might include experiencing symptoms of depression or anxiety. In more severe cases, emotional and behavioural changes might include agitation, uncontrollable crying, or aggressive behaviour.

Duration of Symptoms

It is difficult to predict how long the symptoms of TBI will persist. The symptoms of TBI are most severe in the weeks immediately following the injury and then begin to show improvement. Many of the brain functions that were compromised immediately following the injury recover as the swelling of the brain decreases over time. With more severe injury, the individual may require ongoing support and healthcare.

Disability associated with TBI

Brain injury is often called the ‘invisible injury’, because other people cannot always see the cognitive and emotional changes that have occurred as a result of the injury.  The experience of disability is caused from the social and physical environment surrounding the person, which may inhibit their movement or personal expression.

The symptoms of TBI can interfere with an individual’s ability to re-engage in many activities of daily living. After a moderate to severe TBI, an individual may experience difficulty participating in family, social and recreational activities, and returning to work. An individual with severe symptoms of TBI might require some degree of assistance to manage his or her activities of daily living. This additional assistance might be provided by members of the family or by a carer (family or non-family carer).

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Other Problems Associated with TBI

There are a number of other health or psychological health challenges that can co-occur with TBI. For example, fractures or internal injuries might also be sustained in the motor vehicle crash that caused the brain injury. These additional injuries can complicate the course of treatment and recovery of the TBI. Individuals who have had a TBI often report experiencing symptoms of pain. In attempting to cope with the aftermath of their injuries, some individuals who have had a TBI resort to excessive use of alcohol or pain medication. The presence of these additional problems can complicate the path of recovery of TBI.

TBI affects not only the injured individual but affects the family as well.  These challenges are often a direct result of the injury and although the person with brain injury may have appear to have a changed personality or behaviour, these symptoms are not the fault of the person with the brain injury. Often, the person with brain injury will not be fully aware of their behaviour or cognitive changes. These changes in mood or behaviour of the individual with TBI (such as angry outbursts, short temper, fatigue, confusion, aggression, impulsivity) can bring additional stresses to members of the family. The person may also experience an altered sense of who they are, or their identity.   In the same way as the individual with the TBI might require assistance or care in order to effectively manage the life changes brought about as a result of the injury, the family members will also require some degree of assistance and care. There are several support options for families impacted by traumatic brain injury, and the treating health professionals and medical team will be able to provide advice regarding the nearest support services.


The Treatment of Traumatic Brain Injury

All traumatic brain injuries are different, and what works for one person may not work in the same way for someone else. This is to be expected after a brain injury, and it can take some time for the individual, their family and the health and medical team to decide on what is most suitable for the individual.

The treatment needs of the individual with a TBI will change along the path of recovery.

Immediately following injury, emergency life saving measures may need to be provided. As symptoms are stabilised, the individual might require medication and rehabilitation services in order to maximise the probability that he or she might be able to participate as fully as possible in important activities of his or her life.


Some rehabilitation interventions might focus on assisting the individual in completing basic activities of daily living; other rehabilitation interventions might focus on upgrading the individual’s employment-related skills to allow the individual to resume occupational activities. The individual might require modifications to his or her environment to ensure that necessary supports are in place to ensure safety and the highest level of independence possible.


Rehabilitation is an important aspect of recovery after traumatic brain injury, especially for more severe injuries. The rehabilitation and resource needs of the individual who has sustained a TBI will change through the lifespan. Immediately following injury, the rehabilitation focus might be on developing basic life skills. At a later point in rehabilitation, the focus might change to independent living, and perhaps even vocational development. The goal of most rehabilitation efforts will be to maximise full participation and optimum quality of life despite the limitations that were brought about by the TBI. The treatment of TBI is not just about reducing the severity of symptoms. Full participation in important life activities is as important as reducing the severity of symptoms, and rehabilitation can assist in getting someone ‘back on track’.

Rehabilitation services will typically include occupational therapy, physiotherapy, psychology, speech pathology, and nursing care. Some symptoms of TBI might persist for a long period time. Individuals who have sustained a TBI can resume important family, social and even occupational activities in spite of fact that some of their debilitating symptoms persist. The individual may receive ongoing rehabilitation services once they have left hospital and moved back into the community.

Life after traumatic brain injury

Traumatic brain injury represents a major life event.  It often means that the person and family will need to adjust to a ‘new’ life and every day will bring different challenges. But, rest assured, there is life after brain injury.  Over time, people with brain injury can experience full and satisfying lives after such an event.  Engaging in meaningful activities and things that are enjoyable will restore a sense of self, as will personal relationships and having control over one’s life again. It will be important to seek out support services, and community networks that provide healthcare and social interaction. The availability of services will depend on where the person lives in Australia, but the treating health professionals and medical team will be able to link the person and their family with key services.

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