A left-side brain injury can lead to difficulties with language and reasoning skills, among other side effects.
To help you better understand these types of brain injuries, this article will explain some functions the left side of the brain performs. Then, we will cover the most common side effects of left hemisphere brain damage.
Finally, we’ll also discuss some effective ways to help recover these side effects.
Understanding Left Side Brain Injury
The brain acts as the control center for the entire body and is responsible for both physical and cognitive abilities. It consists of two hemispheres, each of which governs the opposite side of the body. For example, the left hemisphere commands movement on the right side of the body, and vice versa.
For most individuals, the right side of the brain is responsible for non-verbal, intuitive actions such as musical and artistic ability. The left hemisphere, on the other hand, is in charge of verbal and logical functions.
Some specific functions the left hemisphere controls include:
- Logic and reasoning
- Number skills
- Analytic thought
- Right-hand control
- Sequential thinking
The left side is also considered the “language hub” of the brain. It is where the bulk of your language abilities lie, particularly your ability to produce and understand language.
Therefore, most people with left-side brain injuries have difficulty speaking, a condition known as aphasia.
We’ll take a closer look at aphasia, and the other effects of left hemisphere damage, next.
Effects of Left-Side Brain Injury
Left hemisphere damage can cause a variety of problems, depending on the location of the injury.
Below are some of the major side effects of left side brain injury:
Aphasia is a language disorder that affects a person’s ability to produce and understand speech. It can also cause difficulties with reading and writing.
There are several types of aphasia that a person can develop after a left-side brain injury. The three most common are:
- Global aphasia. This is the most severe form of aphasia. A person with global aphasia cannot speak, read, or write and can barely understand others.
- Broca’s aphasia Also known as “expressive” or “non-fluent” aphasia. With Broca’s aphasia, a person can understand what others say, but cannot produce their own words. This type is the most common after left-side brain injuries.
- Wernicke’s aphasia. This form is the polar opposite of Broca’s aphasia. With Wernicke’s aphasia, a person can speak fluently, but cannot understand others.
The best way to treat aphasia in any form is to work with a speech-language pathologist. These specialists can create a custom plan that best fits your needs.
2. Apraxia of Speech
Not all language problems are caused by aphasia.
Sometimes after a left-side brain injury, the brain loses it’s connection to the facial muscles. This leads to a condition called apraxia of speech.
With apraxia of speech, your brain cannot coordinate the movements of all the different muscles in your mouth. This can make it difficult to form and pronounce words correctly.
3. Dysarthria (slurred speech) and dysphagia (difficulty swallowing)
Two other speech disorders associated with left hemisphere brain damage are dysarthria and dysphagia.
Dysarthria refers to a weakness of the mouth and tongue, which causes a person to slur their speech. Dysphagia , on the other hand, causes weakness of the throat muscles used for swallowing.
The two disorders often appear together because speaking requires many of the same muscles used for swallowing.
Once again, speech therapy exercises are the best ways to treat these problems.
Make sure you practice your swallowing exercises under the close supervision of a speech therapist to prevent any risk of choking.
4. Right-Side Weakness (hemiparesis)
Because the left side of the brain controls movement on the right side of the body, left-side brain injuries can sometimes cause right side weakness (hemiparesis).
In severe cases, a person can experience full paralysis on their right side (hemiplegia).
These conditions occur because of damage to the primary motor cortex, which lies in the frontal lobe of the brain. If the left half of the motor cortex suffers damage, the right side of the body will be affected.
After damage to the left motor cortex, a person may struggle to:
- Lift their right hand
- Move the fingers on their right hand
- Control right side of their face
To restore movement, you will need to practice physical therapy exercises that utilize your affected muscles.
5. Computation and Reasoning Problems
Finally, a left-side brain injury can cause issues with math and logic skills.
It can also affect abstract reasoning and organization skills. People with left hemisphere damage often struggle to keep their thoughts straight, which can make problem-solving more difficult.
Some other cognitive skills that left hemisphere injuries can affect include:
- Ability to gather and sort information
- Strategy and planning
These skills and others make up a group of abilities known as executive functions. Fortunately, speech therapists can help you improve these functions.
Treatments for Left-Side Brain Injury
While the effects of left-side brain injuries can be serious, they are not necessarily permanent. In fact, the brain possesses a remarkable healing ability known as neuroplasticity. This ability allows the brain to reorganize neurons and compensate for damaged areas.
This means the brain can actually change its structure so that different, undamaged portions take control of lost functions. Therefore, even if your brain’s left hemisphere was damaged, you can still restore at least some of the abilities that you lost.
To activate neuroplasticity, you must engage in intensive, repetitious exercise. This applies even if you want to regain cognitive skills. Some of the best therapies that utilize neuroplasticity to overcome left-side brain injury include:
- Speech therapy. Speech therapy is probably the most useful therapy for left-side brain injury. Not only can it help you overcome aphasia and apraxia, but therapists can also teach you how to improve your cognitive abilities.
- Constraint-induced movement therapy. For patients with right hemiparesis, strapping down their left arm will force them to use their neglected arm. This will activate neuroplasticity and allow them to regain function much sooner.
- Cognitive therapy. Patients that struggle with logic and reasoning may benefit from cognitive therapy exercises. These help train the brain to process information in a more efficient manner. Usually, a Speech Language Pathologist is the best person to help get you started with cognitive therapy.
Once again, the key is to practice these therapies as frequently as possible. If you can, try to do your exercises at home for a few minutes every day. Talk to your therapists for instructions on the best way to do this.
Shared Effects of Left Side Brain Injury and Right Side Brain Injury
While we’ve discussed how the left hemisphere controls certain functions, the brain itself works together as a whole.
This means the effects of left and right side brain injury are not always as clearly defined as this article may seem. Some individuals with left-side brain injury may even share a few of the symptoms of right hemisphere damage, and vice versa.
Therefore, if your symptoms do not line up perfectly with this list, that is no reason to worry.
With that said, we hope you now have a clearer picture of left hemisphere damage and the steps you need to take to enhance your recovery.