Personality Changes After Brain Injury: What a Clinician Needs to Know

One of the most intimidating issues for caregivers, families, and the person affected by brain injury is: personality changes.

Personality changes are reported by family, friends, and caregivers to be the biggest contributor to caregiver burden and burnout – even more so than continence issues or mobility issues. How often have we heard that this person is ‘no longer themselves’ after their injury? Here, we are going to examine whether personality changes with brain injury – how we can adjust our expectations – and tips for therapists and families to navigate this tricky field.

How common are personality changes after brain injury?

A study published in the Archives of Physical Medicine and Rehabilitation found that 59% of persons with severe brain injuries demonstrated changes in personalities as rated by their significant other. That’s pretty significant! So what does the clinician need to know?

What kind of changes to personality might you see post brain injury?

Poor Frustration Tolerance

When a person is tired or stressed, new situations, or when they are in a bad mood, they may have trouble with their ability to handle frustration. A person who has had a traumatic brain injury (TBI) may become more likely to lash out in anger and become physically or verbally aggressive.

Trouble following through with tasks

People who have suffered a TBI  may have difficulty staying focused or paying attention. Attention is the foundation of all other cognitive skills. Having trouble paying attention can frequently result in additional issues and challenges, such as: a greater propensity to become distracted, difficulty completing tasks, difficulty switching attention from one task to another, difficulty remembering and learning new information, difficulty maintaining lengthy conversations or focusing on one conversation when multiple people are talking.

Poor self-awareness in social situations

Everyone has issues with self-awareness to some degree;, but people who have experienced a TBI  are not truly adept at assessing our own capacities. Damage to brain structures that allow us to self-monitor can make it harder to be aware of oneself after a TBI. It can be difficult for people with TBI to adjust their perception of what they can and cannot do because they may lose the ability to self- monitor how well they perform everyday tasks. Self-awareness difficulties following a TBI are thought to be primarily caused by damage to the brain itself, but emotional coping and adjustment issues can also have an effect on self-awareness.


Family members of people who have a TBI often say that the injured person has a “short fuse,” “flies off the handle” easily, is irritable, or has a quick temper. Studies show that up to 71% of individuals with TBI have issues with increased irritability. The person with the TBI might scream, use bad language, throw things, slam doors, slam fists into things, or threaten or hurt family members or others.


After someone experiences a TBI, one of the most common issues is anger. When someone with  a TBI struggles with anger, a number of factors often come together. Often times, people with TBI are angry because of the injury itself and/or the issues that may have arisen as a result, such as physical disabilities, the loss of a job, friends, money, and control over one’s life. Also, people who had anger challenges prior to their injuries could continue to have magnified issues after.  People who are unfamiliar with the survivor’s injury are often quick to assume that the person can control how they are reacting, when in fact, they cannot.   To put it another way, the brain regions that normally prevent a person from acting or feeling irate have been damaged and cannot perform their duties as effectively. This means that the person’s tolerance for anger is lower, making it easier and more intense for them to get angry. We can tell that the brain injury is directly responsible for this impulsive anger when:

  • Anger episodes may be in response to minor events.

  • The person experiencing the anger episodes is surprised, embarrassed, or distressed by them.

  • Anger is often made worse by physiological stress, such as fatigue, pain, or low blood sugar.

Need help understanding how to navigate these tricky areas? Check out this course


Aggression  following a TBI is more common than you might think. Research in The Journal of Neuropsychiatry and Clinical Neurosciences conducted a study in 2009 to evaluate 67 individuals who had suffered a TBI for the first time. Within 3 months of the injury, over 28% of them displayed post-TBI aggression (primarily verbal). In most cases, the aggression was associated with the onset of depression among other psychosocial problems. When things don’t go as planned or when there are disagreements with family or coworkers, they are frequently cited as having a short temper. Outbursts of verbal or physical aggression may outburst when this is associated with poor behavioral control.

Read this real life story about Hope, an OT and wife of a person with TBI

How can we help patients, families, and ourselves to deal with personality changes post brain injury?

There are three main ways to assist with managing personality changes post TBI:  stay present, calm, and don’t argue; provide structure; and make a plan and meeting their needs.  Keeping those things in mind is definitely easier said than done, but it’s important to remember that recovering from a brain injury is a process, meaning the person will continue to evolve and change and we, as the caregivers/professionals, have to evolve and change with them. 

For more information on these strategies see this article:  Agitation and Brain Injury (TBI):  How to Manage

It’s also important to have the person with the TBI continue to receive therapy in some form to assist with self-awareness and improving overall insight. This can come in form of physical, occupational, or speech therapy in a structured clinic setting or also from a neuropsychologist who is well versed in managing people who are recovering from a TBI.  If therapy is not possible at the moment, there are a wealth of resources available online to assist you. 

For more information on tips to improve social skills in something with an acquired brain injury, see this article:  Social Skills Post ABI – this took is a game changer!

As a loved one of the person with the TBI, it’s key that you adjust your expectations and almost ‘grieve’ who the person was before their injury.  It’s important to meet them where they are in that moment, and not where you want them to be, or where you think they should be.  Self-care is very important – seeking out therapy for yourself is just as important as therapy for your loved one.  It’s ok to need some help with adjusting – no one is expected to seamlessly transition after a major life altering event. 

The entire family is affected when someone sustains a TBI. According to research, caregivers of people with TBI may experience feelings of burden, distress, anxiety, rage, and depression.  And interestingly enough, personality and behavior changes are stated by caregivers to be the largest things that contribute to caregiver burden. Recognizing how stressful this situation can be and seeking support services are important if you are caring for a partner, spouse, child, close friend, or other relative who has a TBI.

As a caregiver, you will probably find it challenging to obtain sufficient and appropriate services for your loved one. It’s important to know that you will need to continually advocate for your loved one, as well as yourself.  Staying well informed and grounded are going to be the most important things that will help you continue assisting your loved one with managing their brain injury

Interested in becoming a CBIS? Check out the Certified Brain Injury Specialization (CBIS) Training

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