7B. Aphasia

• What is aphasia?

  A language disorder caused by brain damage
• Why must language research be conducted on humans?

  There are no animal models for language
• What are the methods used to study language in neuroscience?

  • Anatomy: Insights from the articulatory tract
  • Dysfunction: Research on aphasia
  • Brain imaging: Techniques like fMRI and PET
• What does linguistics focus on?

  The composition of language
• What is psycholinguistics?

  The study of psychological processes in language
• Which hemisphere is typically specialized for linguistic operations?

  The left hemisphere
• How does handedness affect language lateralisation?

  Left-handed individuals are more likely to have right language dominance, but it is still rare
• Who were Paul Broca and Carl Wernicke?

  Researchers who discovered language areas in the brain
• What did Broca's patient "Tan" demonstrate?

  Could only produce one word but understood speech
• What area of the brain is associated with Broca's aphasia?

  Broca's area in the left inferior frontal gyrus
• What are the characteristics of Broca's aphasia?

  Difficulties with language production but comprehension intact
• What test assesses the extent of Broca's aphasia?

  The Boston Diagnostic Aphasia Test
• How do patients with Broca's aphasia typically feel about their condition?

  They are usually aware and frustrated
• What is a key feature of Wernicke's aphasia?

  Fluent speech that lacks meaning
• What brain damage is associated with Wernicke's aphasia?

  Damage in the posterior left hemisphere
• What are the types of aphasia and their characteristics?

  • Conduction aphasia: Understands and produces speech, struggles to repeat
  • Global aphasia: Cannot understand or produce speech
  • Transcortical motor aphasia: Similar to Broca's, but repetition intact
  • Transcortical sensory aphasia: Similar to Wernicke's, but repetition intact
  • Isolation aphasia: Cannot understand or produce speech, but repetition intact
  • Anomic aphasia: Struggles to name objects
• What does Lichtheim’s model of speech perception and production involve?

  1. Auditory cortex processes heard words
  2. Wernicke's area interprets speech sounds
  3. Arcuate fasciculus connects Wernicke's and Broca's areas
  4. Broca's area generates speech content
  5. Motor cortex controls speech output
• What is the Wernicke-Geschwind model?

  A model of language processing in the brain