Language and brain

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Language and the Brain

Where is the ability to use language?

In the brain

Neurolinguistics

• The study of the relationship between language and the brain

Parts of the Brain

• The left hemisphere

• The right hemisphere

Brain Areas

• Boca’s area: described as anterior or speech cortex. Boca, a French surgeon reported in

1860s that damage to this specific part of the brain was related to extreme difficulty in producing speech.

• It was noted that damage to the corresponding area on the right hemisphere had no such effect.

• This finding was first used to argue that language must be located in the left hemisphere

Wernicke’s Area

• Carl Wernicke was a German doctor who, in

1870s, reported that damage to this part of the brain was found among patients who had speech comprehension difficulties.

• This finding confirmed the left-hemisphere location of language ability and led to the view that Wernicke’s area is part of the brain crucially involved in the understanding of the speech.

The motor cortex

• This part generally controls movement of the muscles (for movement of hands, feet, arms, etc)

• Evidence that this area is involved in the actual physical articulation of speech comes from the work reported in 1950s by Penfield and Roberts.

• These researchers found that by applying minutes amounts of electrical current to the specific areas of the brain, they could identify those areas where electrical stimulation would interfere with normal speech production.

The Arcuate Fasciculus

• It is a bundle of nerve fibers that forms a crucial connection between Wernicke’s area and Broca’s area

The Localization View

• The brain activity involved in hearing a word, understanding it, then saying it, would follow a definite pattern

• The word is heard and comprehended via

Wernicke’s area.

• The signal is then transferred via the arcuate fasciculus to Broca’s area where preparations are made to produce it.

• A signal is then sent to the motor cortex to physically articulate the word.

• The localization view is one way of saying that our linguistic abilities have identifiable locations in the brain

Tongue Tips and Slips

• Language users experience occasional difficulty in getting the brain and speech production to work together smoothly

• There is, for example, the tip-of-the-tongue phenomenon, viz. you know the word, but it just won’t come to the surface

• A similar type of speech error is commonly described as a slip-of-the-tongue, which results in tangled expression such as a long

shory stort ( for ‘make a long story short’), and the ‘thine sing’ (for ‘the sign thing’), or word reversals, as in use the door to open the

key and a fifty-pound dog of bag food

• This type of slip is also known as Spoonerism, after Reverend William A. Spooner at Oxford

University who was renowned for his tongue slips.

• Most of the slips attributed to him involve interchange of two initial sounds as when he addressed a rural group as Noble tons of the

soil, or complaint to a student who had been absent from classes: You have hissed all my mystery classes.

• A less commonly documented type of slip is the slip of the ear; it results from hearing

“grey tape” as “great ape”.

Aphasia

• It is an impairment of language function due to localized cerebral (i.e. brain) damage which leads to difficulty in understanding and/or producing linguistic forms.

• The most common cause of aphasia a stroke resulting from violence on the head

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