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The complexity of language

The ability to communicate effectively is a skill that most people take for granted. It isn’t often that we stop to think about the complex nature of speech and language.  

For example, have you ever stopped to consider how our brain is able to process over 200 words per minute every hour of the day without tiring? Or why, when you finish reading this sentence, your voice will instinctively rise to mark the use of question? Further, how do you know that the combination mgla could not possibly be a word, but the combination flast is permissible?

Speech Language Pathologists

These and other questions are investigated by speech language pathologists (SLP). Formerly known as speech therapy, the allied health discipline of speech language pathology encompasses the diagnosis, assessment and treatment of communication and swallowing disorders. 

Communication – the means by which we understand and make ourselves understood – can breakdown in the areas of speech, fluency, voice, language use, hearing, reading and writing. As one in seven Australians experience some form of communication disability, the role of the SLP in hospitals, educational settings, nursing homes as well as specialist and private practice, is growing. 

Speech language pathologists work as part of a multidisciplinary team, often alongside physiotherapists, occupational therapists, doctors and nurses. As the caseload of the SLP is so varied, their responsibilities may include treatment of swallowing disorders following stroke, working with parents of a new born baby with a cleft palate, reducing voice strain in teachers and providing information and rehabilitation to patients who have suffered an acquired brain injury. 

As with all frameworks for speech pathology intervention, it is the aim of the SLP to treat not only the presenting impairments, but to also determine their impact on a patient’s activities and participation. 

Consequently, it is the role of an SLP to not only diagnose and assess patients, but to consider the patient as a whole, understanding the impact of impairment on a patient’s social, emotional and vocational aspects of life.

Speech, Language and Acquired Brain Injury

Human communication comprises three fundamental neurological processes that may become impaired as the result of an acquired brain injury. The overall aim of these processes is to facilitate effective communication, in which we can plan and execute exactly what we want to say. The three steps involved include: 

  • Understanding and organisation of a thought, e.g. knowing that saying ‘hello’ requires the production of four distinct sounds h-e-l-o. 
  • Programming of the motor components, e.g. knowing that to produce the /h/ you need to release a quiet stream of air from the back of your throat. 
  • Execution of the thought, e.g. actually producing the word ‘hello’ by using certain speech muscles. 

A breakdown can occur at any one or more of these stages, depending on the location and severity of the acquired brain injury.


Chapey, R. (2001). Language Intervention Strategies in Aphasia and Related Neurogenic Communication Disorders. Lippincott Williams and Wilkins: Sydney. 

Brookshire, R. (2003). Introduction to Communication Disorders. Mosby: St Lois. 

Duffy, J. (2005). Motor Speech Disorders. Substrates, Differential Diagnosis and Management. Elsevier Mosby: Missouri. 

Goodglass, H. (1983). The Assessment of Aphasia and Related Disorders. Lea and Febiger: Philadelphia. 

Speech Pathology Australia Website, 2007.