NEUROLINGUISTICS

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NEUROLINGUISTICS

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Contents

• The meaning of Neuro linguistics.
• Brain and language.
• Neuroanatomy of the language.
• Brain and the linguistic capacity.
• Language and Brain Lateralization.
• An amazing fact.
• Second Language acquisition and Brain plasticity.
• Topic notes.

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What is the Meaning ofNEUROLINGUISTICS ?

• Neurolinguistics is the branch of linguistics
  that is concerned with the brain mechanism and
  that underlines the acquisition and use of human
  language, through the study of the neurobiology
  of language.

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Brain and Language,Historical background

• The hypothesis which states the brain is the
  source of language has started by the ancient
  Egyptians and the ancient Greeks.
• The assumption reoccupied peoples attention
  again when
• Paul Broca introduced what is called Brocas
  aphasia, and stated that we speak with the left
  hemisphere in 1869.
• Carl Wernicke introduced another variety of
  aphasia language disorder that occurred to
  patients with lesions.

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Neuroanatomy of the Language

• It is now accepted that the Brocas area and the
  Wernickes area are in the left hemisphere and
  are the two brain regions most closely associated
  with language ability.

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Brain and the Linguistic Capacity

• The fundamental component of linguistic
• capacity is the ability to name or/and to
  associate
• a symbol to an object or an action. That
• ability is dependant on the ability to form
• cross-modals associations between modalities
  (Geschwind, 1964).
• Therefore, nonhumans are incapable, even with
  intense training, of forming the type of modal
  representation
• necessary for metaphorical matching.

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Language And Brain Lateralization
Left hemisphere
Right hemisphere
Corpus Callosum

• The human brain is separated by a longitudinal
  fissure called the Corpus Callosum which
  separates the brain into two distinct cerebral
  hemispheres.
• Language, as a reasoning function, is lateralized
  to the left hemisphere of the brain.

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Language And Brain Lateralization
Brocas Area

• Realizing brain function laterality is credited
  to Paul Broca who built his research on Tan, a
  patient who had speech deficit in 1861.
• After Performing a post-mortem autopsy, Broca
  determined that Tan had a lesion in the left
  cerebral hemisphere. This area is called Brocas
  area.
• Broca included that deficit in speech production,
  Brocas aphasia, is caused by damage in Brocas
  area.

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Language And Brain Lateralization
Wernicke Area

• In 1874, Wernicke announced another variety of
  aphasia, that occurred in patients
  
• with lesions in the back portion of the left
  hemisphere, known as Wernickes Area.
• Unlike Brocas patients, those patients spoke
  fluently but they had numerous
• instances of lexical errors word
  substitutions, or what is known as Wernickes
  aphasia.
• Those patients also had difficulty in
  comprehending speech.

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An Amazing Facts

• When baby utters his first Mama at age one,
  adults exult that he has finally begun learning
  to speak. But his lessons in language began long
  before. Even in the womb, the infants neural and
  vocal senses are being actively developed (John
  L Locke, 1994).
• Locke and others found out that the right
  hemisphere plays an important role in language
  during the first three to seven years of life.
• In the act of speaking, the right side of an
  adults mouth tends to open first because motor
  control of the right side of the body and control
  of the speech are both vested in the left
  hemisphere of the brain.
• In young children, both sides of the mouth are
  opened at the same time because the right side of
  the brain which controls the left side of the
  mouth houses speech centers

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Second Language Acquisition and Brain Plasticity

• Is human skill to learn more than one language
  mediated to functional or structural change in
  the brain?
• Learning a second language increases the
  density of the
• left inferior partial cortex.
• The degree of structural reorganization
  in this region is
• modulated by the proficiency attained
  and the age at
• acquisition.