Broca's area

Broca's area
Broca's area is made up of Brodmann areas 44 (pars opercularis) and 45 (pars triangularis).
Broca's area (shown in red)
Details
Part ofFrontal lobe
ArteryMiddle cerebral
VeinSuperior sagittal sinus
Identifiers
MeSHD065711
NeuroNames2062
FMA242176
Anatomical terms of neuroanatomy

Broca's area, or the Broca area (/ˈbroʊkə/,[1][2][3] also UK: /ˈbrɒkə/, US: /ˈbroʊkɑː/[4]), is a region in the frontal lobe of the dominant hemisphere, usually the left, of the brain[5] with functions linked to speech production.

Language processing has been linked to Broca's area since Pierre Paul Broca reported impairments in two patients.[6] They had lost the ability to speak after injury to the posterior inferior frontal gyrus (pars triangularis) (BA45) of the brain.[7] Since then, the approximate region he identified has become known as Broca's area, and the deficit in language production as Broca's aphasia, also called expressive aphasia. Broca's area is now typically defined in terms of the pars opercularis and pars triangularis of the inferior frontal gyrus, represented in Brodmann's cytoarchitectonic map as Brodmann area 44 and Brodmann area 45 of the dominant hemisphere.[7]

Functional magnetic resonance imaging (fMRI) has shown language processing to also involve the third part of the inferior frontal gyrus the pars orbitalis, as well as the ventral part of BA6 and these are now often included in a larger area called Broca's region.[8]

Studies of chronic aphasia have implicated an essential role of Broca's area in various speech and language functions. Further, fMRI studies have also identified activation patterns in Broca's area associated with various language tasks. However, slow destruction of Broca's area by brain tumors can leave speech relatively intact, suggesting its functions can shift to nearby areas in the brain.[9]

  1. ^ "Broca's area". The American Heritage Dictionary of the English Language (5th ed.). HarperCollins. Retrieved 8 September 2019.
  2. ^ "Broca's area". Lexico UK English Dictionary. Oxford University Press. Archived from the original on 2022-08-26.
  3. ^ "Broca's area". Merriam-Webster.com Dictionary. Merriam-Webster. Retrieved 8 September 2019.
  4. ^ "Broca's area". Collins English Dictionary. HarperCollins. Retrieved 8 September 2019.
  5. ^ Cantalupo C, Hopkins WD (November 2001). "Asymmetric Broca's area in great apes". Nature. 414 (6863): 505. Bibcode:2001Natur.414..505C. doi:10.1038/35107134. PMC 2043144. PMID 11734839.
  6. ^ Kennison, Sheila (2013). Introduction to language development. Los Angeles: Sage. ISBN 978-1-4522-5629-0.[page needed]
  7. ^ a b Dronkers NF, Plaisant O, Iba-Zizen MT, Cabanis EA (May 2007). "Paul Broca's historic cases: high resolution MR imaging of the brains of Leborgne and Lelong". Brain. 130 (Pt 5): 1432–41. doi:10.1093/brain/awm042. PMID 17405763.
  8. ^ Hagoort, P. (2014). "Nodes and networks in the neural architecture for language: Broca's region and beyond" (PDF). Current Opinion in Neurobiology. 28: 136–141. doi:10.1016/j.conb.2014.07.013. hdl:11858/00-001M-0000-0019-FEFE-C. PMID 25062474. S2CID 16858289. Archived (PDF) from the original on 2022-10-09.
  9. ^ Plaza M, Gatignol P, Leroy M, Duffau H (August 2009). "Speaking without Broca's area after tumor resection". Neurocase. 15 (4): 294–310. doi:10.1080/13554790902729473. PMID 19274574. S2CID 16683208.