Introduction

Communication starts from infancy. An infant understands that crying will signal the need for food and companionship. As infants grow, they draw associations between sounds and people, and by 6 months of age, they can understand the common sounds in their native language. 

By the age of 3, most toddlers have acquired fundamental skills of speech and language, such as receptive language (understanding what others say) and expressive language (expressing their own thoughts). 

Acquiring speech and language skills early is important, as the brain at a young age is most receptive to learning and understanding sounds and vocabulary. This happens because the cerebellum, the part of the brain responsible for speech and language development, is rapidly maturing during the first years of life.¹

Children with cerebellar agenesis have an absent or partly absent cerebellum, which can cause developmental delays in their speech and language development. 

The importance of the cerebellum

Brain development begins around 3-5 weeks during the gestation period. In week 5, the brain starts dividing into specific parts—the forebrain, midbrain, and hindbrain. Within these parts, there are different regions responsible for different functions.²

The cerebellum is a small structure located at the back of the brain. Despite its small size, it plays a major role in many functions, including: 

• Coordinating movement
• Maintaining balance and posture
• Fine motor control
• Supporting speech clarity and timing
• Thinking and learning processes

At birth, the basic brain structures are formed, but their functions continue to develop and mature throughout childhood and into early adulthood. For example, the cerebellum is structurally present at birth, but it continues to mature throughout childhood and adolescence until it reaches full maturity in the early 20s.³

Healthy cerebellum development during the early years of life is essential for children to learn movement, speech, and language in a smooth and coordinated way, allowing them to gradually integrate these skills into their daily behaviour as they grow.

What is cerebellar agenesis?

Cerebellar agenesis is a rare condition where a child is born without part or all of their cerebellum. Only a few cases have been recorded.

It can be diagnosed from the moment of birth up to the first few decades of an individual’s life with MRI and CT scans. Such a wide diagnostic window is attributed to the fact that symptoms range between patients; some are asymptomatic, while others present with ataxia, dysarthria, or motor abnormalities.  

The causes remain unknown; however, most cases are linked to genetic factors that prevent the development of the cerebellum during the gestation period. 

The absence of a cerebellum leads to developmental delay, cognitive impairment, learning disabilities, and inability to coordinate movements. 

Many children with cerebellar agenesis grow into adulthood presenting mental, physical and neurobehavioral abnormalities.⁴

How cerebellar agenesis affects speech and language

The way we receive and perceive information is regulated by the brain. Incomplete development or absence of certain brain parts has a definitive impact on the development of a child. 

The absence of the cerebellum affects the way a child understands spoken information, as well as the ability to communicate their thoughts and engage in conversation. 

Speech challenges

Children with cerebellar agenesis usually have delayed speech. Their ability to communicate develops more slowly than in children without the condition, and many struggle with pronouncing words clearly.

Some children manage to develop basic communication skills, while others rely more on hand gestures and body language.⁵

Language challenges

Language is a complex skill, and while most children begin developing it within the first 2 years of life, every child picks it up at their own pace. For children with cerebellar agenesis, language development happens more slowly, depending on how the brain has adapted. Common challenges include following instructions, understanding long and/or complex sentences, the meaning of new words, grammar, vocabulary, and sentence structure. 

Children with cerebellar agenesis will often rely on alternative strategies, such as using simpler or shorter sentences, and avoiding using linking verbs and connective words like “is”, “and”, and “the”. These issues can make their speech harder to understand, even if they know what they want to say.

Overall, language milestones like saying the first words and language progression are likely to be slower compared to children without cerebellar agenesis.⁶

Additional developmental concerns 

Total or near-total absence of the cerebellum may lead to motor, cognitive, and behavioural challenges.

Motor skills delays

Mild to moderate motor skills may be present in children with cerebellar agenesis, which can become more prominent after the 2nd year of life. Children may require assistance while walking, usually from objects that they can use to help them stabilise themselves. Arms are often raised to acquire balance while walking. 

Children may also find it challenging to coordinate movements, such as understanding when to start or stop certain actions at the right moment, or how to make smooth transitions between steps in a movement. 

Difficulties with precise movements may also be present, such as picking up a small object. 

Learning differences

Apart from language difficulties involving grammar and vocabulary, children with cerebellar agenesis may also find it challenging to understand how to react in social or everyday situations. 

For example, when learning how to walk, they have slow and sometimes ineffective reactions to possible dangers such as falling.⁷

Emotional and social challenges

The cerebellum is associated with emotional processing. Children with cerebellar agenesis face difficulties expressing emotions, which can lead to impulsivity. 

Social withdrawal is often observed and is linked to the development of psychiatric disorders such as depression and obsessive-compulsive disorder.⁸

Can children with cerebellar agenesis learn to communicate?

Children with speech and language difficulties can eventually learn to communicate with the right care and support. 

Speech therapy can be highly beneficial, especially if initiated from a young age. It can help with:

• Improving movement coordination for speech
• Enhancing timing, rhythm, and sequencing
• Reinforcing language, memory, and attention

How can parents and caregivers help?

In the first 2 years of a child’s life, the brain is receptive to many new situations and can adapt quickly to new information. The cerebellum develops fast during these years, and this rapid growth supports coordinated movements, speech and language processing, and social skills.⁹

If you notice a slow pickup of these skills, it is wise to refer the child to a speech and language therapist to get the support they need. Early intervention is key to developing fundamental speech and language skills that they will later build on as they grow older. 

The symptoms and abilities of each child with cerebellar agenesis can vary widely, but with patience, encouragement, and consistent practice, there is a great chance of eventually developing speech and language skills. 

It is important to remember that every child is different, and while some may eventually speak relatively quickly, others might need a longer time and, in the meantime, rely more on alternative communication methods. 

As a parent and caregiver, it is important to provide a safe and supportive environment in which the child will feel comfortable navigating their learning journey.¹⁰

FAQs

Will children with cerebellar agenesis ever speak?

Cerebellar agenesis may come with developmental delays, language difficulties and motor delays. However, with a holistic support system from an early age, it is possible to gain fundamental speech and language abilities when young. 

How do I know that my child has cerebellar agenesis?

If you notice a difficulty in speech, language understanding, and motor abilities, a healthcare provider may test for cerebellar agenesis by performing MRI and CT scans to detect the absence of the cerebellum. However, it is important to keep in mind that a delay in speech and language development alone is not necessarily a sign of cerebellar agenesis, as each child develops it at their own pace.

Do children with cerebellar agenesis have a normal life expectancy?

Cerebellar agenesis is not life-threatening on its own, and children are expected to have a normal lifespan. 

Summary

Cerebellar agenesis is a rare disorder in which a child is born without a cerebellum. The cerebellum is responsible for various functions, including speech and language development, and motor skills. coordination, learning abilities and emotional expression. 

These functions are picked up by children in the first few years of their lives, but children with cerebellar agenesis may experience a slower rate of development. While the development of these critical skills may be affected, development overall doesn’t stop. With the right support system and care, speech therapists and families can provide a holistic support system that can make a big difference in children’s learning journeys.