Brain Injury does NOT equal Lack of Intelligence

We should probably start with defining intelligence. Intelligence can be defined as the ability to solve complex problems or make decisions with outcomes benefiting the that particular individual that involves problem-solving and decision-making.  These are functions of the nervous systems, including the brain, so intelligence is closely related to the nervous system. There is not just one way to be intelligent or display intelligence.  In fact they are 8 types of intelligence, with a 9th known as “existentialist intelligence” that has been recently introduced by Howard Gardner, a psychologist from Harvard. Gardner’s theory suggests that traditional psychometric views of intelligence are too limited. 

What does brain injury look like?  Do you know?  What does someone look like who has a brain injury?  Do you think of them as being unable to think anymore, or as a drooling incapacitated individual who has somehow lost their ability to be independent or do for themselves?  What if they tell you they have a brain injury but nothing shows up on a CT Scan or an MRI – would you still believe them?  What if someone didn’t start to have symptoms until years later? Do you think this is even possible or would you think symptoms should show right away?  This writing is dedicated to any professional that works with or comes into contact with any person who may have sustained a brain injury.

I personally have had numerous concussions (brain injuries) throughout my life. I mean, anytime you hit your head and see “stars or sparkles” – guess what?  That is a brain injury. That being said, I never gave a 2nd thought to them because I never had any seeming lasting damage or long term effects. Let’s face it, the education about concussions was not as advanced back when I was a kid, nearly 50 years ago.  I mean, the fabric of education and discovery around medical science changes on a daily basis, and I am sure as a society we will continue to learn even more about our brains as time goes on. 

When I sustained a closed head injury in 2014 my opinion about head injuries, what they looked like, and how they presented would forever change.  In addition to multiple orthopedic fractures, I also had to overcome this new way of existing in a body I no longer recognized.  I could not think the same way I used to.  I could not pull up my words as fast.  My recall was crappy and yet I still maintained the same level of intelligence as before my injuries, just the ability to process and trouble with memory made it near impossible to feel like I was able to express it in the same ways I was used to. Based on multiple accounts, certificates of merit, and other input given to me throughout my life, I was considered to be highly intelligent before all my injuries, so why after that accident was I now just testing as “average”.  Why couldn’t I recall basic information, simple words, and struggle with putting my thoughts together? Why did my taste and smell and ability to be in crowds and around noise change?

Noone professional, or in roles to educate me on this really seemed concerned about this at first.  Just me. They would say things like, “you communicate really well so you’ll be fine”, or “most of society is average so you are good”, or “you should be happy you aren’t worse”, or “everybody gets headaches or forgets things”. They weren’t listening, only getting caught up in the numbers of the “average” of their other patients – not dealing with me as an individual or taking my concerns, or the concerns of my family seriously. I was worse – they just couldn’t see it.  “Great”, I told myself, “I am happy for everyone else, but this is not normal for me”.

How could these providers look me in the face and say I was fine, especially since they didn’t even know me before my injuries?  How could they be so callous, indifferent, and lack basic knowledge in a field where they should be teaching me about these changes?

  I knew I was different. My family knew I was acting different. The me I used to be was gone.  Killed in that accident.  I was now living with a stranger in my body. I knew my thinking and processing and memory was off.  It was a daily and sometimes moment to moment battle. Yet since I was suddenly “average” I was okay to those looking at the data and my life.  I was not average to myself.  I was falling apart and while different than those fractures in my body I also sustained and everyone could see, my brain injury they could not see. My injury remained invisible on a regular MRI and CT scan since I didn’t have a skull fracture or hemorrhage.  Apparently the general thought was that the brain swelling that encapsulated my brain and then reduced made me all better.  False!  In fact, I was generally dismissed as just needing to be patient and give myself “time to recover”. 

Then the most miraculous thing happened.  I discovered in my search a special brain scan called a SPECT CT (different than a regular CT scan). Michigan No-Fault was a lifesaver in providing me the opportunity to get this scan done.  The SPECT CT, which showed diffuse axonal shearing in multiple parts of my brain….finally PROOF…something that could be “seen”.  Honestly, that test was a game changer in a lot of ways….but that is another story.

Let’s start here though and focus on what this writing is about to begin with. You can be highly intelligent, experience a brain injury and still be highly intelligent. This is what confuses people who see you and interact with you.  To them, you are still “normal”. A brain injury does not necessarily affect intelligence. Intelligence is a stable trait which includes many aspects of cognitive functioning. Following a traumatic brain injury, the brain is unable to function as well as it did prior to injury. This is why we typically see some difficulties with memory or academics. However, once the brain recovers there is no change in a person’s overall intelligence. Your intelligence is based, depending on the definition of intelligence, on the sum total of your knowledge.

Someone’s IQ can be unaffected by a TBI, but other parts of the brain that “pilot” or guide one’s brainpower can be messed up. Decision-making and complex social interactions can cause major problems in one’s life and career. The individual with high intelligence may still have cognitive problems such as headache, difficulty thinking, memory problems, attention deficits, mood swings and frustration. These injuries are commonly overlooked, especially in those with high intelligence.  Their low threshold of functioning or slower processing speeds may appear as average where prior to injury they would have tested as above average.

Something interesting I discovered in my studies is that the brain of the intelligent person is more complex in appearance, not as soft, and has greater weight relative to size. Additionally, it can be noted that the intelligent brain may have an enlarged prefrontal cortex or parietal lobe relative to other areas of the brain. More intelligent people have more wires, more connections and more complex architectures in their brains. These are reflective of genetics, as well as developmental experience. Also, more intelligent people may enjoy higher processing speed or impulse conduction in brain-wires (axons). But with more complexity in the brain, the net result still could look in performances as much slower decision making resulting in a dulled sense of self, lower test scores compared with their education/experiences, and reduced overall performance compared with their performance before injury.

That being said, Intelligence and personality dysfunctions after minor traumatic brain injury (TBI) (whiplash; slight head impact) incurred in a motor vehicle accident (MVA) were studied in adults after an average interval of 20 months. There was a mean loss of 14 points of Full Scale IQ from estimated preinjury baseline IQ determined from the standardization group (WAIS-R) without evidence for recovery. Personality dysfunctions included cerebral personality disorder, psychiatric diagnosis (30 of 33 patients), post-traumatic stress disorder, persistent altered consciousness, and psychodynamic reactions to impairment. Cognitive loss is caused by interaction of brain injury with distractions such as pain and emotional distress. Unreported head impact and altered consciousness at the time of accident contribute to the underestimation of brain trauma after minor TBI.

 I can tell you this.  There is a saying in the brain injury medical community that if you have seen one brain injury, you have only seen one brain injury because no two brain injuries are alike.  While there are many symptoms that are consistent with each other and may overlap between folks, there is one thing you can be sure of – it is consistently inconsistent.

 In fact, there are a lot of misdiagnoses for ADHD, ADD, and ODD when instead these folks should be screened for history of brain injury and have neuro testing done as well before making a blanket diagnosis.  Now this doesn’t mean that all people diagnosed with ADHD/ADD are misdiagnosed.  However, it does mean that if they have a history of a brain injury it is something worth exploring.

Unless there is objective evidence (evidence you can physically see that is obvious) of brain injury on MRI or CT Scan (hemorrhages, hematoma’s penetrating skull fractures into the brain, etc) people (including uneducated providers) assume the individual expressing symptoms of a traumatic brain injury may be faking, exaggerating, or malingering their injuries or the person has psychological problems that had to have pre-existed before their accident.  The reality is that the majority of mild (mTBI) and moderate brain injuries show normal results on an MRI and CT scans.  That’s right, you cannot see the injury with these particular tests – and a lot of folks develop psychological changes and personality changes as a result of their injuries.

The basic imaging of an MRI or CT Scan also does not show diffuse axonal injuries nor do they show levels of intelligence.

Keep in mind also when working with your patients, clients, or colleagues, that women also tend to have longer recovery times than men with regard to brain injuries as shown in recent studies.  Recent studies on women’s brains finally coming to the front of the class in the scientific community.  This is important because almost all research has previously been done on just men’s brains.

We are learning that there is damage we can’t see with the naked eye that requires special testing (like a SPECT CT) and that is called diffuse axonal injuries (DAI). Someone with diffuse axonal injuries may also have brain inflammation or swelling.  This can lead to restricted blood supply to the brain tissue and brain herniation. Which by the way, does not necessarily affect the person’s intelligence.

Diffuse axonal injuries (DAI) are caused by acceleration, deceleration, and contact forces. DAI affects individual nerve fibers which can lead to a disruption in nerve communication.  DAI is microscopic damage to the axons in the brain neural tracts, corpus callosum, and brainstem, is associated with significant mortality and morbidity. When these forces are great enough it creates a shearing force that severs the axons of nerve fibers, which causes nerve cells to die and can create swelling in the brain. The main symptom of diffuse axonal injury is lack of consciousness, which can last up to six hours or more. A person with a mild or moderate diffuse axonal injury who is conscious may also show other signs of brain damage, depending upon which area of the brain is most affected. Diffuse axonal injury causes cognitive, physical, and behavioral changes that compromise social reintegration, return to productivity, and quality of life of patients and their families. These changes persist beyond the acute phase of treatment and continue for a long period after the traumatic event. Diffuse axonal injury, and more generally TBI, often results in physical, cognitive, and behavioral impairments that can be temporary or permanent.

Due to the diffuse and microscopic nature of the injury, CT scans and general MRIs are typically negative unless small areas of bleeding within the brain are noted within the cerebral cortex or corpus callosum (tracts of white matter in the brain). If a patient presents with unconsciousness and these tests are negative, the medical facility should move onto a different imaging technique to check for DAI. Depending on the severity of the injury and the extent of the damage. A concussion can be considered a mild case of shearing brain injury. At its mildest, DAI can occur unnoticed. 

Another thing for providers to be aware of when dealing with their patients, clients, or colleagues is that tonsillar herniation is a type of cerebral herniation characterized by the inferior descent of the cerebellar tonsils below the foramen magnum. Chiari one malformation is a form of tonsillar herniation and is now known to be caused by trauma (like severe whiplash and traumatic brain injury) or in most cases “symptoms awakened” from trauma.  This is an often overlooked correlation between trauma and DAI and TBI.

The bottom line here is that you can’t get tunnel vision and just assume that because your patient looks okay, that they are okay.  You should keep in mind that a patient knows themselves better than you know them.  If they are telling you that something is wrong and they are different – then listen and take that seriously. 

If a person has a brain injury with long lasting debilitating symptoms, they can still have the same intelligence.  You can have a severe traumatic brain injury with empirical radiological evidence of damage and still maintain your intelligence.   Brain injury does not equal lack of intelligence.  A person’s intelligence is not a solid basis for deciding a person’s extent of disability after an injury.

What I hope you get out of this is a way to relate to, offer help for, and be better informed about brain injuries so you can offer the best possible care to the people you work with.

The High IQ TBI  (a blog which is worth the read about high IQ and TBI – this will take you to a different site)

References:

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BrainInjury.com. 2022. Types of Brain Injury — 12 Unique Classifications. [online] Available at: https://www.braininjury.com/brain-injury

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 Vieira, R., Paiva, W., de Oliveira, D., Teixeira, M., de Andrade, A. and Sousa, R., 2016. Diffuse Axonal Injury: Epidemiology, Outcome and Associated Risk Factors. [online] National Library of Medicine. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5071911/

Wood, R. and Rutterford, N., 2006. Long-term effect of head trauma on intellectual abilities: a 16-year outcome study. [online] National Library of Medicine. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2077538/

Gao, MD, PhD, B., Jiang MD, S., Wang MD, PhD, X. and Chen MD, J., 2000. The Role of Pre-injury IQ in the Determination of Intellectual Impairment from Traumatic Head Injury. [online] Neuro.psychiatryonline.org. Available at: https://neuro.psychiatryonline.org/doi/pdf/10.1176/jnp.12.3.385

Gipe B.C.S, S., 2011. Can Acute Trauma Car Accidents Cause Chiari Malformations?. [online] Dolman Law Group Accident Injury Lawyers, PA. Available at: https://www.dolmanlaw.com/blog/chiari-i-malformations-and-their-relationship-to-acute-trauma/

Johnson Jr, G., 2022. Normal IQ after Brain Injury Doesn’t Rule Out Brain Injury. [online] TBI Law.com. Available at: http://tbilaw.com/normal-iq-after-brain-injury.html

Robinson, C., 2017. Brain Injury does NOT equal Lack of Intelligence. [online] HOPE TBI Help One Person Excel – To Be Independent. Available at: https://hopetbi.com/2017/05/06/brain-injury-does-not-equal-lack-of-intelligence/

(This blog re-post has been updated from Original Post on May 6, 2017)