Introduction

Cerebral palsy (CP) is a group of movement disorders caused by damage to the brain that occurs before birth or in infancy. CP is not one specific diagnosis but rather refers to a number of possible clinical symptoms that an affected person might experience. However, all individuals with CP have disorders of posture and movement. CP is the most common childhood disability with varying symptoms that can include seizures, problems with speech, vision or hearing, spinal abnormalities, joint problems, and intellectual disability.¹ CP is divided into four main types, which are determined by which brain region is affected. The most common is spastic CP, affecting about 80% of those with CP.¹ Spastic CP is characterized by stiff muscles and increased muscle tone. Dyskinetic CP affects control of the limbs, whereas ataxic CP affects balance and coordination. Finally, mixed CP combines symptoms of two or more CP types.

CP can affect a person’s speech, language, and non-verbal communication. Those with CP can have difficulty controlling the structures of the face like the tongue and oral muscles used for speech, leading to disorders such as dysarthria, a condition that causes unclear speech. This article will explore the importance of speech therapy in those with CP, highlighting the role that speech therapy can play in improving the communication skills of those affected.²

Understanding cerebral palsy and speech

Communication challenges related to cerebral palsy can encompass a wide range of speech and language difficulties. These may include trouble understanding and producing spoken language, speech that is hard for others to comprehend, struggles with reading, and writing, and challenges using language effectively in social contexts.³ Up to 36% of children with CP have dysarthria, a speech disorder that leads to unintelligible speech, and 19-32% cannot speak at all. Those with the dyskinetic CP type have the greatest risk of dysarthria and inability to speak.⁴ 

CP researchers have used the concept of “speech subsystems” to describe the different facets of speech production, including the respiratory (breathing), phonatory (voice production), resonatory (nasal quality), and articulatory (speech sounds) systems. Issues in any of these subsystems caused by CP can result in dysarthria. For instance, difficulties with breathing coordination can impair voice quality, problems with the resonator subsystem can lead to excessive nasality, and issues with articulation can cause slurred speech.⁵ Individuals with cerebral palsy may have difficulties producing facial expressions, gestures, and body movements. Children with CP, even if they are verbal, often use communication in a less flexible manner compared to their peers.⁶ 

Children with CP often encounter challenges with reading and spelling. These literacy difficulties are linked to issues with nonverbal cognition, speech, and working memory. Language development may also be affected by cognitive impairment. About 48% of children with CP have cognitive impairment ranging from mild to severe. Those with difficulty speaking or difficulty being understood may face greater social isolation and reduced quality of life. Speech therapy can help those with CP to maximise their communication skills and increase opportunities for social communication.⁷

Role of speech therapy in CP

Speech therapy is a treatment designed to address disorders of language, speech, and swallowing. Speech-language pathologists (SLPs) work with both children and adults with CP to address various speech and communication challenges. For individuals with CP, speech therapy aims to reduce speech impairments, enhance motor skills related to speech, improve intelligibility, and boost social communication abilities. The treatment plan is highly individualised and is based on a careful and thorough assessment of the person’s individual abilities and needs. Treatment will also include collaboration with families and caregivers to help facilitate communication between the patient and family. In the initial session, the therapist conducts a comprehensive assessment, which may include reviewing the child's medical history, examining the oral cavity, performing hearing tests, and evaluating speech clarity, language, fluency, and cognitive abilities. Based on this assessment, the therapist diagnoses the child’s condition and develops a customised treatment plan. The therapy typically involves exercises designed to address the child's specific communication or swallowing challenges.⁸  

Speech therapy can enhance communication by strengthening and coordinating the muscles necessary for speech, improving cognitive understanding of language, and refining oral motor skills. A speech therapist creates a personalised plan for each child with cerebral palsy, tailored to their specific communication needs. This plan might include teaching sign language, using writing and drawing for communication, practising non-verbal gestures, or employing tools such as voice synthesisers, picture boards, and augmentative communication devices. These approaches address various aspects of communication, including pronunciation, vocabulary, listening skills, word comprehension, fluency, conversational abilities, and swallowing issues. SLPs utilise a range of exercises, tools, and assistive devices to support improvements in speech, literacy, and overall communication.

Through therapy, a child will acquire skills to:

• Resolve pronunciation difficulties
• Use words accurately
• Understand grammar
• Manage speech pace
• Construct complex sentences
• Increase vocabulary
• Improve conversational skills
• Comprehend spoken and written language
• Enhance memory and recall
• Relate spoken words to their written forms

Speech therapy techniques for CP

There are a number of techniques, exercises and tools that speech therapists may utilise in the treatment of individuals with CP. A licensed speech therapist collaborates closely with each child to create a personalised plan aimed at improving their communication skills. They often provide exercises to help children grasp concepts like gestures, words, numbers and sounds more effectively. Techniques may include:

• Vocal Conditioning: Breaking words into syllables and repeating specific sounds
• Mirror Exercises: Mimicking sounds or words while watching in a mirror
• Whistleblowing and Breathing Exercises: Training mouth muscles for sound production, strengthening abdominal muscles, and controlling breathing
• Manual Tools: Utilising picture boards, books, word cards, or flip charts for expression and communication^9,10

Articulation is a speech therapy technique used to help individuals produce sounds and pronounce words correctly. The SLP will use structured exercises to focus on the production of specific sounds until they are mastered. The therapy will start with syllables and work up to words, sentences, and conversation. Speech therapy may also involve training parents and other communication partners and using aids such as symbol charts or devices with synthetic speech. Augmentative and Alternative Communication (AAC) is a type of therapy that helps individuals communicate with tools rather than speaking. AAC includes both “aided” and “unaided” forms of communication. Unaided modes include natural, nonverbal forms like gestures, facial expressions, and manual signs, which rely on motor control and interpretation by others. Aided modes involve external tools, such as communication boards with symbols or devices that produce speech through synthesised or recorded means.¹¹

For individuals with severe disabilities, using a combination of unaided and aided modes can be beneficial. They may use different methods in various contexts, such as signing at home and using a picture-based system or speech-generating device elsewhere. For those with severe speech limitations, AAC can be beneficial. AAC has been shown to help children communicate more frequently and in more diverse contexts, expand their vocabulary, and improve their narrative skills.¹²

In motor speech therapy, the SLP will use exercises to strengthen oral muscles like the mouth, tongue, and lips. They will also work to improve skills such as the use of your breath during speech and enhancing the quality of your voice. Exercises can include blowing bubbles or whistling to strengthen oral muscles and improve breath control, breathing exercises to improve diaphragm strength, jaw, lip and tongue exercises like pressing a tongue depressor against the tongue to improve tongue strength, and the use of flashcards to help reinforce word associations. Tools used in speech therapy can include computers and tablets, paper, books, flashcards, tongue depressors, straws and more.¹³ 

Speech and language therapy offers significant benefits by helping children with communication issues develop effective communication skills. Early SLT aims to help children build essential communication skills for future independence. This support enhances their learning, participation in school and home activities, and relationships with others. Key benefits include improved socialisation, better relationships with friends and family, and consistent, effective communication of ideas.¹⁴

Summary 

Speech therapy plays a pivotal role in enhancing the communication abilities of individuals with cerebral palsy. By addressing the unique challenges posed by CP, such as dysarthria and cognitive impairments, speech-language pathologists tailor interventions to improve not only speech clarity but also social interaction and overall quality of life. Through a combination of vocal exercises, augmentative communication tools, and personalised treatment plans, speech therapy empowers those with CP to navigate their daily lives more effectively and connect with others more meaningfully. Early and ongoing therapy not only fosters better communication skills but also contributes to greater independence and a more inclusive social experience. As research and techniques continue to evolve, the commitment to providing targeted, compassionate care will remain essential in supporting individuals with cerebral palsy in reaching their full potential.