The corpus callosum connects the left and right hemispheres of the brain and allows information to pass to both sides. While damage to the corpus callosum is rare, it can cause a variety of symptoms that may affect cognitive, emotional, and/or physical abilities. With the help of rehabilitative therapies, individuals may be able to overcome the effects of corpus callosum damage.
To help you understand what to expect after corpus callosum damage, this article will discuss:
What Is the Corpus Callosum?
The corpus callosum is a hard, C-shaped structure found in the middle of the brain. It acts as a connective pathway that links the left hemisphere and the right hemisphere of the cerebral cortex.
Each hemisphere of the brain controls movement and feeling on the opposite side of the body. The corpus callosum acts as a bridge so that input from the left side of the brain can transfer to the right side and vice versa.
Besides serving as a bridge between the two hemispheres, the corpus callosum also plays its own role in higher cognitive function. Researchers have shown that it is involved in complex abilities such as:
- Memory
- Learning
- Executive functions
- Three-dimensional vision
- Visual reaction time
Injury to the corpus callosum can cause problems with these cognitive functions. However, not all the effects of corpus callosum damage are cognitive.
What Happens If the Corpus Callosum Is Damaged?
Because the corpus callosum is responsible for relaying information between both hemispheres of the brain, it is crucial for balance and coordination. Both hemispheres of the brain must work together to coordinate movement, and therefore damage to the corpus callosum may result in difficulties with balance and motor function.
Along with providing communication across both hemispheres of the brain, the corpus callosum also contributes to cognitive function. Therefore, corpus callosum damage can also cause cognitive and emotional changes.
Here are some of the most common effects related to corpus callosum damage:
Pseudobulbar Palsy
Pseudobulbar palsy is a condition that affects the ability to control facial muscles. This can make it difficult to chew, swallow, or speak.
Individuals with pseudobulbar palsy may also demonstrate:
- Dysarthria, or slurred speech
- Dysphagia, or difficulty swallowing
- Dysphonia, or spasms in the vocal cords that cause poor voice quality
- Emotional lability, or exaggerated mood swings
Although the brainstem controls most facial muscles, these signals must pass through the corpus callosum. Therefore, if it becomes damaged, difficulties with facial movement can occur.
Speech and Movement Ataxia
When corpus callosum damage hinders communication between both hemispheres of the brain, it can lead to speech and movement ataxia. Ataxia refers to a lack of control or coordination of voluntary movements.
Depending on which muscles are affected, this could cause problems with:
- Walking
- Picking up objects
- Speech
- Eye movement
- Swallowing
A speech-language pathologist can diagnose and help rehabilitate any speech-related issues like ataxia of speech or swallowing difficulties after brain injury. A physical or occupational therapist can help diagnose motor ataxia and help rehabilitate it, which we will discuss later.
Alien Hand Syndrome
Perhaps the strangest potential symptom of corpus callosum damage is a condition known as alien hand syndrome. While it most commonly affects the left hand, it can affect the right in some cases. This condition causes the hand to seemingly move and act on its own without any cognitive control or awareness from the person.
These movements are not simply random, involuntary muscle spasms either. Instead, the affected hand performs goal-oriented tasks, as if it is being controlled by someone else.
For example, the person’s hand might pick up an object, or touch their face, or button their shirt without any conscious input. Sometimes the hand might engage in counterproductive actions, such as closing a door that the other hand just opened. In some extreme cases, the hand has tried to harm the patient by choking them.
People with alien hand syndrome often feel like their hand is foreign. But they do not deny ownership of their hand, as occurs in other neurological disorders, such as left neglect.
Rehabilitation for Corpus Callosum Damage
Rehabilitation after neurological injury revolves around the phenomenon of neuroplasticity: the mechanism the brain uses to rewire itself. When the corpus callosum sustains damage, neuroplasticity allows other, healthy areas of the brain to take on lost function.
Many of the effects of corpus callosum damage can be remedied, at least partially, through rehabilitation. Because the effects can affect cognitive-, motor-, or speech-related skills, the rehabilitation process may involve working alongside several different therapists.
Speech & Cognitive Therapy
Individuals that sustained facial movement problems, pseudobulbar palsy, or speech ataxia can benefit from speech therapy exercises. Because every brain injury is different, a speech-language pathologist can help choose the most appropriate exercises for each individual. For example, individuals with swallowing difficulties may practice swallowing exercises, which are a type of speech therapy exercise.
For those who develop cognitive impairments such as memory loss or executive dysfunction, cognitive rehab exercises can be helpful. These exercises challenge the person to practice various cognitive skills that may have been affected by corpus callosum damage.
For example, if attention has become impaired, a cognitive exercise like symbol hunting can help retrain attention. When practiced consistently, cognitive exercises help activate neuroplasticity and encourage cognitive function to improve over time.
This symbol hunting exercise is an example from the CT Speech & Cognitive Therapy App. It contains an expansive library of different speech and cognitive exercises that patients can practice at home.
Physical & Occupational Therapy
When corpus callosum damage causes difficulty with movement, physical and occupational therapists can help. Physical therapists can assign therapeutic rehab exercises that target balance and mobility. Occupational therapists can do the same, as well as help with independence with the activities of daily living.
Unfortunately, there are very few treatments available for alien hand syndrome. Some studies have shown promising results using mirror box therapy. However, more research is still needed.
But in the meantime, occupational therapists can help individuals adapt to using only one hand. They can also provide helpful ways to compensate for the uncontrollable hand. For example, in extreme cases, it might be more practical to strap it down with an arm sling to prevent it from moving.
Understanding Corpus Callosum Damage
The corpus callosum is a crucial brain structure that connects the right and left hemispheres. Damage to it can cause cognitive and physical effects and, in rare cases, alien hand syndrome.
Fortunately, there are many therapy modalities available that can help. Individuals with impaired balance (ataxia) can benefit from physical and occupational therapy. Others with speech difficulties such as apraxia of speech or swallowing difficulties can benefit from speech therapy. The key to recovery is to activate neuroplasticity through therapeutic exercises. With time and diligence, survivors of corpus callosum damage can maximize their chances of recovery.
The post Corpus Callosum Damage: What to Expect and How to Treat It appeared first on Flint Rehab.
