Aphasia


Introduction and definition[edit | edit source]

Aphasia is defined language disorder, a condition where a person has difficulty with their language or speech which is most commonly caused by damage to the left side of the brain for example, after a stroke, head injury or brain tumor. Aphasia leaves a person unable to communicate effectively with others.[1][2][3][4]

Description[edit | edit source]

As mentioned above aphasia is a condition resulting from damage to areas of the brain responsible for language, which for most people is located in the left hemisphere of the brain if the person is right handed [5][6]. The condition presents as an impairment to comprehension or formulation of language and is often caused by diseases and disorders affecting the brain, with cerebrovascular accident being the most common cause[7].

[8]

Anatomical relevance[edit | edit source]

Areas of the brain responsible for language:

  • Werncike's area
  • Broca's area
  • Arcuate fasciculus

The Wernicke's area is located in the temporal lobe and is responsible for processing visual and auditory information. It is the center for comprehension and planning of words. Broca's area on the other hand is located in the frontal lobe of the brain. It is responsible for motor execution of speech and sentence formation. While the arcuate fasciculus is the neural connection between both areas[9].

Symptoms of aphasia[edit | edit source]

People suffering from aphasia have difficulty reading, listening, speaking, typing or writing which makes it difficult for them to understand language.

Speaking is most commonly affected and the person affected with aphasia struggles with choosing the right word to speak. They either sound the word wrong or they fail to put together the right words to form a sentence.  

Aphasia can occur all by itself or in conjunction with other disorders, like visual difficulties, mobility problems, limb weakness, and problems with memory or thinking skills.

Patient speaks in short or incomplete sentences that don’t make sense or use unrecognisable words as they have difficulty finding words to use.

Patients do not understand other people's conversation. Patient also do not understand what they read and while writing, their sentences don’t make sense.

A vital point to remember is; aphasia affects a person's ability to communicate, it doesn't affect their intelligence.[1][10]

Causes of aphasia[edit | edit source]

Aphasia can occur from a number of brain injuries and conditions such as:[1][10]

Types of aphasia[edit | edit source]

Aphasia can be broadly classified as either fluent or non-fluent.[11]

  1. Non-Fluent aphasia includes:
    • Broca's
    • Transcortical motor
    • Mixed transcortical
    • Global
  2. Fluent aphasia types are:
    • Wernicke's
    • Transcortical sensory
    • Conduction
    • Anomic[7]

The most common types of aphasia include:

  • Broca's aphasia.
    • Occurs from damage to the frontal lobe.
    • Patients may understand what is being said them, know what response to give but may often reply with short phrases with so much effort.
    • Patients may become frustrated from their difficulty in communicating clearly making some sliding into depression.
    • May often present with right hemiparesis/hemiplegia as the frontal lobe is also important for motor movements.
    • Also referred to as expressive aphasia.
  • Wernicke's aphasia
    • Occurs from damage to Brodmann area 22 of the temporal lobe also known as Wernicke's area
    • Is characterised by patients composing and speaking long, complete sentences that have no meaning. They may even formulate non-existent new words to express themselves.
    • They experience difficulty in understanding speech.
    • These patients are often unaware of their speaking blunders.
    • It is also known as receptive aphasia.
  • Global Aphasia
    • May have trouble understanding simple words and sentences.
    • May be limited in their ability to speak and comprehend language.[5]

Other forms of aphasia are:[7]

  • Conduction Aphasia is caused by lesion located in the arcuate fasciculus. Patients with this type of aphasia experience difficulties with or are unable to repeat words spoken to them. They realise the errors they make and endeavour to correct them.
  • Transcortical Sensory Aphasia is caused by lesions around but not affecting the Wernicke's area. Patients may be able to repeat speech fluently but have difficulties with comprehension.
  • Transcortical Motor Aphasia is from lesions around but that do not affect the Broca's area. Patients have a tendency to remain silent and may repeat one to two words. They may also be able to repeat long complex phrases although their speech may not be fluent.
  • Mixed Transcortical Aphasia results from lesions around the language areas of the brain but that do not affect them. Patients in this category have severe speaking and comprehension impairment but can repeat long, complex sentences.
  • Anomia is the mildest form of aphasia and is from damage to angular gyrus. It is characterised by patients having difficulties with finding words.

Diagnosis of aphasia[edit | edit source]

  • As per NHS, diagnosis of aphasia can be carried out by clinician – either a speech and language therapist or a doctor.
  • Diagnosis of aphasia can be reached by performing a simple exercise where the patient is asked to name objects in the room, repeat words and sentences, and read and write. The aim of the tests is to understand a person's ability to understand basic speech and grammar along with expressing words, phrases and sentences. It also tests the patients ability to communicate, read and write.
  • Making a diagnosis may also include the use of imaging procedures like Computed tomography (CT), Magnetic resonance imaging (MRI), Positron emission tomography (PET).[1][10][5][11]

Differential diagnoses[edit | edit source]

  • Dysphonia
  • Dysarthria
  • Cognitive communication disorder
  • Altered mental status from encephalopathy or delirium[7]
  • Apraxia of speech
  • Deafness[12]

Treatment of aphasia[edit | edit source]

  • Recovery of language skills is usually a slow process, though if the brain damage is minimal, it's possible to recover language skills without treatment. Although most people make significant progress, few people regain full pre-injury communication levels.
  • Most people undergo speech and language therapy to rehabilitate their language skills and improve communication. Chance of recovery is poorer for people with aphasia resulting from a progressive neurological condition.
  • Speech therapy and language therapy is beneficial for patients with aphasia; however, no single treatment has proven most advantageous, it mainly aims to improve the ability to communicate. It helps by restoring as much language as possible, teaching how to make up for lost language skills and finding other methods of communicating. Speech therapy and language therapy is most effective when it begins soon after the brain injury. This may include use of computers and computer-assisted therapy is especially helpful for relearning words.
  • Example of speech and language therapy technique: The aim of these tasks is to improve patients ability to remember the meanings of words and link them with other words. If a patient has difficulty expressing him/her self, patient is asked to practise naming pictures or judge whether certain words rhyme or mean the same or opposite. Patient is also asked to repeat words that they say, with prompting if necessary. If the patient is able to complete tasks with single words, therapist will work on patients ability to construct sentences further progressing to brief paragraphs.
  • Patients therapist also helps the patient to develop alternatives to talking, such as using gestures, writing, drawing or communication charts.
  • Promising strategies to reduce permanent language deficits, such as pharmacological agents, for example drugs that are known to improve blood flow to the brain and enhance the brain's recovery ability by helping reproduce the depleted neurotransmitters; are being studied as a treatment of aphasia. But more research is needed before these treatments can be recommended.[13]
  • Other treatments include brain stimulation which is being studied and is under research for treatment of aphasia. Research has shown, it may help improve the patients ability to name things. But no long-term research has been performed as of yet.
  • Family involvement is a crucial component in treatment of aphasia and family members are encouraged to participate in therapy sessions, simplify language, clarify meaning as needed, minimise distractions such as a loud radio or TV whenever possible during the conversation; family is also asked to include the patient in conversations and ask the patient for their opinion in family matters; family members are asked to avoid correcting the patients speech and allow the patient plenty of time to talk. It is also vital to help the patient get involved outside the home and seek out for support groups.[1][5][11][12]

Relevance to physiotherapy[edit | edit source]

Physiotherapists get to manage patients with neurological conditions that may and often lead to aphasia. It is important to be knowledgeable about the condition and types to aid appropriate referral if/when detected by the physiotherapist in the course of patient care, and also to optimise interaction with patients.

References[edit | edit source]

  1. 1.0 1.1 1.2 1.3 1.4 NHS choices. NHS; 2021 March 23. Available from: https://www.nhs.uk/conditions/aphasia/
  2. Damasio AR. Aphasia. New England Journal of Medicine. 1992 Feb 20;326(8):531-9.
  3. Berthier ML. Poststroke aphasia. Drugs & aging. 2005 Feb;22(2):163-82.
  4. Geschwind N. Aphasia. New England Journal of Medicine. 1971 Mar 25;284(12):654-6.
  5. 5.0 5.1 5.2 5.3 5.4 National Institute on Deafness and Other Communication Disorders, Aphasia. Available from: https://www.nidcd.nih.gov/health/aphasia (accessed 28 July, 2021)
  6. Fridriksson J, den Ouden DB, Hillis AE, Hickok G, Rorden C, Basilakos A, Yourganov G, Bonilha L. Anatomy of aphasia revisited. Brain. 2018 Mar 1;141(3):848-62.
  7. 7.0 7.1 7.2 7.3 Le H, Lui MY. Aphasia. StatPearls [Internet]. 2021 Jun 13.
  8. TED-Ed. Aphasia: The disorder that makes you lose your words - Susan Wortman-Jutt. Available from: http://www.youtu.be/-GsVhbmecJA [last accessed 29/7/2021]
  9. Ochfeld E, Newhart M, Molitoris J, Leigh R, Cloutman L, Davis C, Crinion J, Hillis AE. Ischemia in broca area is associated with broca aphasia more reliably in acute than in chronic stroke. Stroke. 2010 Feb 1;41(2):325-30.
  10. 10.0 10.1 10.2 Aphasia . Johns Hopkins Medicine. Available from: https://www.hopkinsmedicine.org/health/conditions-and-diseases/aphasia
  11. 11.0 11.1 11.2 Aphasia. NIH. Available from https://www.nidcd.nih.gov/health/aphasia [last accessed 11/11/2021]
  12. 12.0 12.1 Le H, Lui MY. Aphasia. InStatPearls. 2021 Jun 13. StatPearls Publishing.
  13. Wortman-Jutt S, Edwards. Poststroke Aphasia Rehabilitation: Why All Talk and No Action? Neurorehabilitation and Neural Repair. 2019 Mar 22;33(4):235–44. ‌