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Speech - The Brain

aphasia language motor center

The speech center lies in the parietal lobe of the left hemisphere of the brain for right-handed persons and most left-handed. The area of the brain responsible for motor control of the anatomic structures is called Broca's motor speech area. It is named for Pierre Paul Broca (1824-80) a French anatomist and surgeon who carried out extensive studies on the brain. The motor nerves leading to the neck and face control movements of the tongue, lips, and jaws.

The language recognition center usually is situated in the right hemisphere. Thus a person who loses the capacity for speech still may be able to understand what is spoken to him or her and vice versa. The loss of the power of speech or the ability to understand speech or the written word is called aphasia.

Three speech disorders-dysarthria, dysphonia, and aphasia-result from damage to the speech center. Dysarthria is a defect in the articulation and rhythm of speech because of weakness in the muscles that form words. Amyotrophic lateral sclerosis (Lou Gehrig's disease) and myasthenia gravis are two diseases with which such muscle weakness can be associated. Dysphonia is a hoarseness of the voice that can be caused by a brain tumor or any number of nonneurologic factors. Aphasia can be either motor aphasia, which is the inability to express thoughts in speech or writing, or sensory aphasia, the inability to read or to understand speech.

The ability to speak is inherent in the human species. An infant is born with the ability to learn language but not to speak. Language is passed from one generation to the next. Children learn basic language easily and at a young age. From that time they add to their vocabulary as they accrue education and experience. A child will learn a language with the regional inflections inherent in his parents' and peers' speech.


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about 4 years ago

I am 50 years old. Last March I became ill and my vice slurred. It sounded as if I was drunk even though I don't drink. I went to the emergency room and they performed immediate surgery on me. When I finally awoke (which the doctors did not think I would) my voice was affected and still is. I was told I had suffered a mastoid infection so severe it penetrated my skull and entered the left side of my brain. My voice was affected but not the comprehension of words or sounds. Even though I lived for which I am thankful my voice impediment aggravates me. I live in Toledo, OH and would like to find a good therapist who can help me with this problem. Is there any help? If so, who?

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over 6 years ago

I have not seen anything in your article that helps me. My mother in law who is 75, has been experiencing slurred speech only when she is up and about, when she is laying down, her speech is fine, her legs are also affected in that they are lifeless when this happens, could this be because of a pinched nerve? or is it an artery problem.

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about 4 years ago

my mom is 79. for the past 3 years she gets her words mixed up. her words are not always reliable or they are not always appropriate.she can not speak in long sentences anymore. she walks slow. she moves slow. she has not had a major stroke but maybe a tia which may have left a lesion in the speech center of her brain. i am looking in the boston area for clinical trials which may help regain her reliable and appropriate speech . mom understands what you are saying however she can not always respond with her thoughts or her feeling on what is being said. does anyone have a suggestion?

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over 4 years ago

I am looking for information and hope that my 40 year old son will recover his speech after a stroke that impacted his entire right side and of course, his speech...this is most disheartening...

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almost 5 years ago

Are you serious, sounds like she is suffering from permanent deficits of a stroke.

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almost 5 years ago

Very helpful - my daughter has some brain damage which is affecting her Broca's area and it makes sense now with the frontal lobe damage why she searches for words and finds it hard to understand new words.

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over 1 year ago

oops please ignore the post I just sent it had the wrong email address...LYME needs to be ruled out for many neurological issues including aphasia and Dysarthia;

Do not overlook Lyme disease,even a negative blood result does not necessarily mean its not a false negative

PEACE,

Kathy

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over 1 year ago

I will continue to send you all the information. As an Advocate I have often networked with some great MDs and know some on the faculty of Harvard. Do NOT lose hope...until we have turned over all the stones on your mother's journey. read below it is my guess some of these indiv have LYME Love and prayers,

Kathy

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about 3 years ago

speech