Language Centres Flashcards
Location of language centres
In most, brocas and wernickes in left hemisphere, where most Lang processing occurs
Broca’s area
Speech production
Posterior portion of the frontal lobe of the left hemisphere
Broca’s aphasia: problems producing speech
Discovered through observation of leborgne
Leborgne
Could only pronounce single syllable of ‘tan’
Post mortem found damage to posterior region of the frontal lobe, left hemisphere (broca’s)
Gardner and Zurich broca’s aphasia
Found terms of the classes of words that are relatively unaffected in some patients with BA
Nouns and verbs seem relatively unaffected but prepositions and conjunctions cannot be spoken
Wernickes area
Understanding language and accessing words
Posterior portion of the left temporal lobe of the left hemisphere
Wernickes aphasia
Impaired ability to understand language, inability to extract meaning from spoken/ written word
Damage to wernickes (research by wernickes)
Damage close to auditory cortex had specific language impairments, they could speak but unable to understand language and displayed anomia
Able to speak fluently when able to access words- doesn’t impact production
Interaction between two language centres
Wernickes area then broca’s then motor cortex to speech production
Neural loop between both
Negatives of localisation of brain function: holistic theory
- argues localisation is largely incorrect
Lashley (1950) found in rats brains no specific area involved in memory, stored all over
Equipotentiality theory: motor and sensory localised but not higher brain
Positive of localisation case studies
Support from case studies eg leborgne
Unable to produce speech and found damage to lesion on the posterior position of the frontal lobe
Rehabilitation suggests no localisation
Would be no plasticity if function was localised
Case of EB: recovered most language abilities despite removal of left hemisphere through intense rehab
Yet never fully recovered: some localisation
Could be how brain communicated rather than specific regions
Brain regions are interdependent in that they interact with each other in order to work
Process information such as reading and movement through different areas
Language production may not be confined to broca’s alone
More recent research (better equip such as brain imaging) shown diff results eg dronkers found when reexamined Leborgne using MRI that there was damage elsewhere
Involve networks rather than areas?
Individual differences in language areas
Pattern of activation observed in response to various language activities can vary from one person to the next
Significant gender differences in size of brain areas linked to language e.g. Women have proportionally larger brocas and wernickes than men
