Neurobiology of language

Question 1

What regions of the brain are implicated in language from ‘lesion analysis’?

Answer 1

left inferior frontal, temporal and inferior parietal lobes

Question 2

Which patients did Broca describe with expressive dysphasia?

Answer 2

Leborgne and Lelong published by Broca 1861

Question 3

What is the problem of lesion analysis to determine functional significance of the brain?

Answer 3

The lesions are often extensive i.e. not specific enough to a single brain region and extent of compensatory plasticity is unknown

Question 4

What is the modern understanding of language representation?

Answer 4

1) Language is distributed into large scale cortical and subcortical networks;
2) How different brain regions are connected by particular fibre pathways (hodology);
3) Language regions are also involved in other non-languistic regions

Question 5

What are the steps of speech production?

Answer 5

1) Prelexical intention to communicate
2) Translation into lexical units (words)
3) Temporal sequence of words
4) Phonological encoding
5) Speech generation

Question 6

What systems are involved with speech generation?

Answer 6

Close coordination of the sensory-motor system with respiratory system, laryngeal motor (phonation) and face motor (phonation) involving multiple cortical / subcortical regions, 6 cranial nerves (5, 7, 9, 10, 11 & 12)