Aphasia is the most common language disorder post-stroke, with one third of all patients diagnosed with stroke experiencing it.
Communication itself is quite a complex neural process. It involves a careful sequence of expression, muscle movements, breathing, speaking, and comprehension. When a person who has had a stroke experiences speech difficulty, word-finding difficulty, or speaks with made-up or inappropriate language, they are highly likely to be experiencing aphasia.
Key Types of Aphasia
- Expressive (non-fluent): speech production is halting and effortful. In severe cases speech is reduced to single words; however comprehension remains intact.
- Receptive (fluent): comprehension is poor, often producing jargon and nonsensical words and phrases.
- Anomia: word-finding difficulty; person uses non specific nouns but is able to describe the intended word.
- Global: severe impairment of both receptive and expressive language, usually associated with a large left-hemispheric lesion.
- Primary progressive: gradual loss of language function, usually beginning with word-finding difficulties, then grammar and comprehension.
The left cerebral hemisphere of the brain is involved in the process of speech. Damage to these areas often causes communication problems. However, in addition to aphasia, a person’s communication abilities after a stroke can be affected in other ways. One such example is dyspraxia, a condition that affects the co-ordination of messaging from the brain to the muscles associated with speech. This results in a general lack of co-ordination or poorly sequenced word selection when talking. Similarly, a condition known as dysarthria can weaken and paralyse the muscles involved with speech, causing a more general slurring of words.
Receptive aphasia (also known as Wernicke’s aphasia, fluent aphasia and sensory aphasia), is caused by damage to the posterior left portion of brain in the medial temporal/parietal lobes. Receptive aphasia involves a breakdown in the phonological system, removing the person’s knowledge of the sequence of sounds within words; consequently alternative sounds can be used instead. Core elements of the phonological and semantic systems are affected, which significantly impairs the person’s auditory-verbal comprehension (visual comprehension is not as impaired).
There are four language systems used to process, understand and use language.
- Phonological: the sound system of language responsible for recognising distinct speech sounds heard in language.
- Semantic: referred to as the ‘meaning system’ allowing for the understanding and expression of language nuances.
- Pragmatic: functional use of language influenced by culture and context.
- Syntactic: relates to language structure (ie word order, sentence structure and grammar).
People with receptive aphasia may experience the following:
- be unable to understand what others are saying
- experience difficulty in following long and complex sentences/discussions
- lose focus when background noise/distractions are present, or when one or more people are speaking
- be able to read headlines but not able to comprehend the text body
- be able to write but not able to read what was just written.
The main treatment for aphasia is speech therapy. Speech pathologists are able to assess strengths and weaknesses of the aphasic patient’s language and communication skills. By identifying individual strengths, a base can be established from which communication enhancement, comprehension and expression can be improved.
General Aphasia Communication Tips
When caring for a person with aphasia, consider implementing some of the tips below as they will assist the person with aphasia to communicate more easily.
- Reduce background noise and distractions.
- Use clear and simple language.
- Allow appropriate time for conversation, giving the person time to respond.
- Stay on one topic at a time.
- Augment the ‘message’ with other communication modalities, e.g. gestures, facial expression and pictures.
- Converse using adult language (don’t talk down to them).
- Gain the person’s attention first before commencing a conversation.
- Keep your voice at a normal, stable volume.
- Establish the topic of conversation with the person prior to communication.
- Ensure sensory aides are within reach, e.g. glasses, hearing aides, dentures etc.
Specific Receptive Aphasia Communication Tips
Ask questions requiring yes/no responses – determining comprehension through screening is necessary for nurses to modify communication in response to screen outcome. The process you should follow involves asking a yes/no response question to which the answer is known – e.g. “are the lights on in this room?” and then “are the lights off in this room?”. Being able to consistently respond correctly to yes/no questions allows the patient to express their preferences, wants and needs.
Integrate one – to three-stage commands as per the person’s level of understanding. Being able to determine the person’s level of comprehension and capacity to follow directions is important, particularly in regard to safety instructions. Without giving any visual cues ask the patient to follow a simple one-step command, e.g. “make a fist”. If you give a visual cue to the patient, they may simply be following the cue or imitating your movement, rather than following the command. Increase complexity by progressing from a one-stage command to a two- or three-stage command. “Take this piece of paper in your right hand, fold the piece of paper in half with both hands and place it in your lap” is a good example of a three-stage command. This is part of Folstein’s Mini Mental State Examination (MMSE) tool.
Receptive aphasia is initially difficult to treat and less experienced stroke-clinicians on the multidisciplinary team might believe that the prognosis of speech recovery is limited. Despite this belief, receptive aphasia is more likely to resolve than any other form of aphasia. Treatment is centred on establishing the most appropriate mode of communication, gradually increasing frequency and complexity, introducing other communication modalities and exposing the patient to supported social interaction.
- National Stroke Foundation. Clinical Guidelines for Stroke Management 2010. Melbourne Australia ISSBNO-978-0-9805933-3-4, https://strokefoundation.com.au.
- Robson H, Zahn R, Keidel JL, Binney RJ, Sage K, Lambon Ralph MA. The anterior temporal lobes support residual comprehension in Wernicke’s aphasia brain. 2014 Mar;137 (Pt 3):931-43. doi: 10.1093/brain/awt373. Epub 2014 Feb 10.
- Panagiotis G. Simos, Dimitrios Kasselimis, Constantin Potagas, and Ioannis Evdokimidis, Verbal Comprehension Ability in Aphasia: Demographic and Lexical Knowledge Effects, Behavioural Neurology, vol. 2014, Article ID 258303, 8 pages, 2014. doi:10.1155/2014/258303.
- Price CJ1, Seghier ML, Leff AP, Predicting language outcome and recovery after stroke: the PLORAS system. Nat Rev Neurol. 2010 Apr;6(4):202-10. doi: 10.1038/nrneurol.2010.15. Epub 2010 Mar 9/.