Cognitive Impairment and Brain Injury

I tell my patients that a few words are off-limits in my office. The most common culprits? The words stupid and broken. People use words like “stupid” and “broken” to describe their brains after a concussion because their brains don’t do what they used to do. They know that something isn’t right but they’re not sure what.

A brain injury may impact thinking skills, but “broken” is a strong word that doesn’t apply here! This post explains what happens to the brain after a concussion.

In this post we’ll cover: 

• What happens to the brain after a concussion

• Concussion Recovery

• Persistent symptoms

• Cognition treatment

What happens to the brain after a concussion? 

The concussion impact

• A concussion happens when the brain gets tossed around. The brain does not have to get hit directly. But, there is some kind of impact that causes the brain to move quickly in the skull. 

• This movement makes the brain hit the sides of the skull and potentially catch on bony protrusions.

Concussion Pathophysiology 

This physical impact then causes damage to different brain functions. These include: 

• Axonal Damage

  • Axons carry brain signals. A concussion impact causes axons to stretch and tear. When axons are damaged brain signals get disrupted. 

• Chemical Changes 

  • Neurons and neurotransmitters help communicate brain signals. They need to maintain a balance of chemicals to pass messages efficiently. After a concussion, chemicals get out of balance. Ions like potassium and calcium flow in and out of the cell at unusual rates. This disrupts thinking skills.

• Energy Crisis

  • The brain tries to fix this imbalance. This takes a lot of energy. That’s a problem because there’s less blood flow to the brain after a concussion. That means the brain can’t get the glucose (energy) it needs.

Concussion Symptoms 

• These physical and chemical changes may lead to headaches and vision changes. 

• They can also disrupt thinking skills. Slowed processing speed and slowed reaction time are common after a concussion. This makes sense when the brain is low on fuel.

Concussion Recovery

• These changes may sound scary but the brain is usually able to recover in a few weeks. The brain will eventually balance out. It can also make new pathways.

Persistent Changes in Cognition 

Some people take longer to heal from their concussion. About 15% of people develop Post Concussion Syndrome (PCS). PCS is a complex disorder characterized by continued physical, cognitive, visual, sleep, and/or emotional symptoms.

The medical community is still learning about PCS and persistent cognitive symptoms. Prolonged chemical changes may contribute to cognitive problems. Many times, other factors are involved. These factors include: 

• History

  • People with a history of learning disabilities are more likely to sustain a concussion and have persistent difficulties. Prior memory, attention, and/or executive functioning weaknesses may be exacerbated by the injury and take longer to improve. 

• Medical conditions

  • People with persistent brain fog, difficulty concentrating, etc. may have other medical conditions contributing to the problem. Hormone imbalance, autoimmune disease, B-vitamin deficiency, dysautonomia, mental health disorder, etc. all impact thinking skills. Your doctor can help you get tested for other medical conditions. 

• Physical symptoms

  • Changes in balance and vision may be causing your cognitive difficulties. Because thinking skills are complex processes involving different types of sensory input, any change in this system can impact cognition. Some people do not see cognitive improvement until these problems are addressed. A physical therapist can help with balance and headaches and an occupational therapist can help with vision issues. 

  • Migraines and other types of chronic pain can also impact your concentration and energy levels. 

• Coping skills

  • Any time something in life changes unexpectedly it takes time to adjust. Changes in cognition, work/school ability, physical symptoms, etc. are a type of loss. It may take some time to process what has happened. Coping skills impact your ability to adapt and move forward, so if it feels difficult to cope you may want to see a counselor. 

• Stress levels

  • Some people experience stress from the event that caused their concussion. They may also feel stressed because health and daily activities changed suddenly. Or, stress levels were already high before the injury. Stress has a negative impact on thinking skills, sleep, and physical symptoms. Prolonged stress can also delay recovery. Talk to your doctor about stress management if it is impacting your recovery.  

• Executive functioning skills

  • Executive functioning skills help you stay focused and organized. They are important for recovery. Executive functioning skills might be impaired following a brain injury. Attention and working memory are especially vulnerable. This makes learning about your injury and managing your recovery harder. If life feels disorganized and unpredictable, ask your doctor about getting speech therapy to improve these skills. 

• Treatment history

  • Not all healthcare providers have experience with the best approaches to treat mild head injuries. If you have not seen a therapist trained in mild head injury, ask your doctor for a recommendation to a multi-disciplinary concussion treatment team. Some people also benefit from seeing the same healthcare providers for multiple rounds of therapy.

Treatment for Cognition

Your doctor may recommend a few different treatment approaches for cognitive symptoms. Some of the common ones include: 

• Treating other issues: Your doctor may prescribe treatment for other conditions like hormone imbalance, PTSD, and balance or vision issues. Treating these can help your thinking skills. 

• Speech therapy: Speech therapy teaches you strategies to improve your attention, memory, organization skills, etc. so you can function better while your brain is healing. 

• Cognitive retraining: Cognitive exercises don’t cure cognitive issues, but they can challenge your brain during recovery. Your speech-language pathologist may also use them to help you practice “good thinking” skills like monitoring your attention levels and adapting to tasks that are increasingly difficult. 

• Counseling: Your doctor may recommend counseling even if you don’t have a diagnosed mental health disorder. Counseling can teach you coping skills and other strategies that make cognitive challenges easier. 

• Medication: There are some medications that help with attention and memory. 

Key Take-Aways:

• Concussion symptoms are real! Changes in cognition can be linked to specific chemical problems that happen after brain injury. 

• This doesn’t mean that your brain is broken. The brain is usually able to recover from these changes in a few days or weeks.

• About 15% of people experience persistent symptoms. The symptoms might be caused by other issues, though, so it’s important to talk with a doctor to see what else might be contributing to the cognitive issues. 

• You don’t have to wait until you figure everything out to get relief for cognitive problems. There are many compensatory strategies that make life easier. A speech-language pathologist can help you figure out what strategies work best for you.

Sources and additional resources:

The New Neurometabolic Cascade of Concussion

Neurochemical Cascade of Concussion

Concussion: Pathophysiology and Clinical Translation

Pathophysiology of Mild TBI: Implications for Altered Signaling Pathways

Glutamate and GABA imbalance following traumatic brain injury