Cog Neuro: L4 - Neuroscience of Language

Language structure

Rules are language specific

Semantics: the meaning of words, or larger linguistic units

Syntax: how words combine to make a sentence - all the rules in the language that allow us to put sentences together.

Morphology: how words are made – we have bits of words that stand in isolation and carries meaning.
e.g., /desk/ vs. /desk/+/s/

Bound morphemes (s) cant stand in isolation but it carries a meaning (pleural) can only attach to free morphemes that are nouns.

Phonology: how sounds combine to make words
e.g., /spring/ vs. /fpring/

Investigating the neural foundations of language

Unlike other cognitive processes, there is no animal model of language

  • Cannot use techniques like cell recordings and ablations

Lesion-deficit correlation studies

  • Traditional
  • Lesions identified at post-mortem

Brain stimulation studies

  • During operation for epilepsy

Functional neuroimaging studies

  • Use the “subtraction method” to identify differentially active cerebral regions
  • An experimental task and a baseline task and you subtract one from the other to see what is working.

Aetiology of Aphasia

Language deficit caused by damage to the brain

Cerebrovascular accident (CVA – stroke; i.e., sudden damage or death of cells in a localised area of the brain, due to inadequate blood flow therefore death of cells.

  • Embolism – material travels through artery till reaches smaller artery until blocks.
  • Thrombosis – blockage of blood vessels (atherosclerotic material)
  • Haemorrhage- brain bleed (not enough blood reaching/ blood leaking).


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For language, in Middle Cerebral Artery (MCA) – lateral surface we find language areas so this artery is vital.

Not all CVAs are persistent; Transient Ischemic Attacks (TIA) recover fast - mini stroke so don’t leave serious long lasting effects.

Traumatic brain injury (TBI)

Brain tumour

Infection and inflammation (e.g., herpes encephalitis)

Most common cause of aphasia is from a stroke.

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How serious a stroke is depends on where the blockage or Haemorrhage is.

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Who has Aphasia?

Anyone can get it but most people who have aphasia are middle-aged or older. Men and women are equally affected.

According to the National Aphasia Association, 80,000 individuals acquire aphasia each year from strokes

1/5 of all stroke victims will experience some aphasia after stroke

However, most people have never heard of it - just released a stroke awareness questionnaire in UK to test awareness for all ages.

Aphasia = difficulty retrieving words but intelligence is intact - can be mistaken as mentally ill or stupid.