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Exploring the Brain - Three Regions Named after Scientists

Updated on July 28, 2016
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Linda Crampton is a teacher with a first class honors degree in biology. She writes about human biology and the scientific basis of disease.

This illustration shows colour-coded lobes of the cerebral cortex. Pink = frontal lobe, blue = parietal lobe, orange = temporal lobe, green = occipital lobe
This illustration shows colour-coded lobes of the cerebral cortex. Pink = frontal lobe, blue = parietal lobe, orange = temporal lobe, green = occipital lobe | Source

The Amazing Human Brain

The human brain is a fascinating and very complex organ that is only slowly giving up its secrets. It has taken us thousands of years to reach our current state of knowledge about the brain. We still don't understand everything about its structure and function. Many researchers are investigating the brain's activities, however, since it's such a vital part of our lives.

In the past, there was a tendency to name newly discovered body structures after their discoverer. This article describes three brain regions and also includes some facts about the physician-scientists who are forever (as far as we know) linked to them.

Broca's area was named after Paul Broca, a French doctor of the nineteenth century. Carl Wernicke was a German physician. He gave his name to Wernicke's area and lived until the start of the twentieth century. The circle of Willis was named after Thomas Willis, an English doctor from the seventeenth century.

Broca's area (red) is located in the frontal lobe of the cerebrum (yellow), which is the largest part of the brain. The cerebral cortex is the surface layer of the cerebrum.
Broca's area (red) is located in the frontal lobe of the cerebrum (yellow), which is the largest part of the brain. The cerebral cortex is the surface layer of the cerebrum. | Source

Broca's Area

The cerebrum is the largest and most obvious part of the brain. It consists of two halves, which are known as cerebral hemispheres. The hemispheres are joined together by a band of tissue called the corpus callosum. Each hemisphere consists of four visible lobes known as the frontal, parietal, temporal and occipital lobes, as shown in the illustration at the start of this article. Broca's area is a patch of tissue located in one of the two frontal lobes. It's usually found in the left hemisphere, but it's sometimes located in the right one.

Broca's area plays an important role in the creation of speech. People who have damage in this area have great difficulty in speaking, even when there is nothing wrong with the rest of their brain or with the body's mechanical components for forming spoken words. Patients may be able to speak a few to a significant number of words but can generally create only short sentences. They often need to pause as they speak. The reasoning and thinking parts of their brain are usually unaffected, which can make the situation very frustrating for them. The disorder is commonly known as Broca's aphasia. It's also referred to as expressive or non-fluent aphasia.

The cerebral hemispheres as viewed from the front of the brain
The cerebral hemispheres as viewed from the front of the brain | Source

Aphasia is an impairment in the ability to produce or understand speech or written material. The disorder ranges from a mild condition to a severe one. Modern treatment techniques (and in some cases the body's healing mechanisms after an injury) may help aphasia.

Recovering from a Stroke and Broca's Aphasia

Paul Broca

Broca's area was discovered by a French neurosurgeon named Paul Broca (1824-1880). In 1861, Broca examined the brain of a man who had recently died. Although the man had been able to produce sounds, the only recognizable word that he had been able to say was "tan". Broca discovered a damaged area in the man's left frontal lobe. He subsequently found damage in the same brain area in other people with similar speech problems. Broca concluded that he had found the part of the brain that was responsible for speech.

Two of the brains that Broca examined were preserved, including the brain of his first patient. Both patients had been severely limited in their speech. In 2007, scientists performed an MRI scan of the preserved brains. They found that although in each case Broca's area was damaged, the injury extended further into the brain. The extent of an injury as well as its exact location likely contribute to the problems experienced by someone with Broca's aphasia.

Broca's area isn't directly responsible for speech. It sends nerve signals to the motor cortex, which stimulates the muscles in the mouth and face to contract in order to produce words.

Wernicke's area is located where the parietal lobe joins the temporal lobe.
Wernicke's area is located where the parietal lobe joins the temporal lobe. | Source

Wernicke's Area

About ten years after Broca's discovery, a scientist named Carl Wernicke discovered another area that is often located on the left side of the brain and is related to speech. Wernicke's area is located mostly in the temporal lobe and partially in the parietal lobe. It's involved in understanding the meaning of spoken words.

People with damage to Wernicke's area can often speak fluently, but what they say makes no sense in relation to the situation. They may sometimes use made-up words as well as real ones and may not show any awareness that they've done this. In addition, they sometimes have a tendency to speak excessively. The disorder is known as Wernicke's aphasia. It's also referred to as receptive or fluent aphasia. Patients may have trouble with understanding written language as well as speech.

Broca's area and Wernicke's area are connected by a bundle of nerve fibres, forming what is known as a language loop. Both areas are important in producing intelligible speech.

This language loop is found in the left hemisphere in about 90% of right-handed persons and 70% of left-handed persons, language being one of the functions that is performed asymmetrically in the brain.

— The Brain page from McGill University

Broca's Area versus Wernicke's Area

Carl Wernicke

Carl Wernicke was a German doctor who was born in 1848. He was killed in an accident in 1905, reportedly while riding his bike. Wernicke is often classified as a neuropsychiatrist. He believed that patients with psychiatric problems had problems in a specific region or pathway in their brain rather than in the brain as a whole.

Wernicke discovered the region that we now call Wernicke's area and found that damage in the area produced aphasia. He was only 26 years old when he published the results of his discovery. He referred to the disorder resulting from the damage as sensory aphasia. The name was later changed to honour his work.

Aphasia is often caused by strokes, especially in older people. Strokes occur in younger people as well, however. Aphasia may also develop due to tumours, head trauma and infections.

Circle of Willis

The circle of Willis is a roughly circular network of arteries located on the undersurface of the brain. Although it belongs to the circulatory system instead of the nervous system, it's often referred to as part of the brain. The arteries play a role in the circulation of blood through the brain.

The circle of Willis is an example of a circulatory anastomosis - a structure in which there is a cross-connection between blood vessels that we would expect to stay separate, such as two different arteries. An anastomosis can provide a backup route for blood if the main passageway is blocked. Interestingly, many people have an atypical circle of Willis. Nevertheless, it's thought that the alternate blood route that it provides can be very useful in certain disorders.

Arteries on the Undersurface of the Brain

Most of the arteries in this illustration are present in a right and a left form. Only one of each pair is labelled. The circle of Willis is the roughly circular section at the top of the illustration.
Most of the arteries in this illustration are present in a right and a left form. Only one of each pair is labelled. The circle of Willis is the roughly circular section at the top of the illustration. | Source

Components of the Circle of Willis

The arteries that make up the circle of Willis are often divided into an anterior group (located at the front of the brain) and a posterior group (located at the back of the brain), which makes them easier to follow.

All of the arteries named below are shown in the above diagram. In order to make the diagram easier to understand, the arteries are cut off at the ends where they disappear from view, change direction or are no longer considered to be part of the circle of Willis. The blood vessels that make up the circulatory system are actually continuous. They branch and merge and change in diameter and direction, but they never simply end.

The anterior group of arteries in the circle of Willis consists of the following blood vessels.

  • Right and left anterior cerebral artery
  • Anterior communicating artery (not paired)
  • Right and left internal carotid artery

The posterior group consists of these vessels.

  • Right and left posterior communicating artery
  • The horizontal parts of the right and left posterior cerebral arteries
  • The tip of the basilar artery (not paired)

Artery Positions in Relation to the Undersurface of the Brain

Source

Thomas Willis

Thomas Willis was an English physician who was born in 1621 and died in 1675. He is often said to be the father of neurology. Neurology is the study of the nervous system.

Since the blood vessels at the base of the brain are visible to the unaided eye, other people noticed the circle of arteries before Willis did. Willis is credited with the circle's discovery, however, due to his meticulous and detailed observations that were far superior to previous attempts to describe the region.

Willis's discoveries were published along with other brain observations in 1664 in a book entitled Cerebri Anatome. The title is a Latin term meaning Anatomy of the Brain. At the time when Willis was alive, scientists created their publications in Latin. Christopher Wren created the illustrations for Cerebri Anatome. He is famous today for his design of St. Paul's Cathedral in London.

Brain Anatomy, Circle of Willis and Stroke

Brain Research

The brain still holds many mysteries. In July 2016, scientists working on the Human Connectome Project announced that they had discovered 97 new regions of the brain. The project is run by the National Institutes of Health in the United States. Its goal is to map the neural pathways in the brain. The plan is very ambitious but has enormous implications in the realm of health and disease.

In the future, scientists may well discover new information about the function of Broca's and Wernicke's areas and the circle of Willis. This will not only be interesting biologically but may also be useful in helping people recover from brain damage. Discovering how the brain works is fascinating and potentially very important.

© 2016 Linda Crampton

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    • FlourishAnyway profile image

      FlourishAnyway 8 months ago from USA

      I recall learning about the first two in college but not the Circles of Willis. Thanks for giving some of the biographical information behind the doctors. Well written and interesting. I find it fascinating that they are still discovering many specify parts of the brain and what they do.

    • AliciaC profile image
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      Linda Crampton 8 months ago from British Columbia, Canada

      Thank you for the visit and the comment, Flourish. I find it very interesting that scientists are still learning more about the brain, too. It's an awesome organ!

    • Mel Carriere profile image

      Mel Carriere 8 months ago from San Diego California

      Fascinating study about the language centers of the brain. The brain is more vast of an unexplored area than the cosmos, I think. Fantastic research!

    • AliciaC profile image
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      Linda Crampton 8 months ago from British Columbia, Canada

      Thank you very much, Mel. I appreciate your comment. I like your description of the brain!

    • bdegiulio profile image

      Bill De Giulio 8 months ago from Massachusetts

      Fascinating Linda. As always, thank you for the education. The brain is an amazing organ. As much as we know about it there seems to be much that we have yet to learn. Thank you for explaining things in simple, easy to understand language, which you do exceedingly well.

    • AliciaC profile image
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      Linda Crampton 8 months ago from British Columbia, Canada

      Hi, Bill. Thank you very much for the comment. I agree - the brain is definitely amazing. It's a very interesting organ to study.

    • Buildreps profile image

      Buildreps 8 months ago from Europe

      Interesting research and your article is fascinating. There is still so much to discover about the brain. A few years ago I watched a scientific series about the brain (don't know the name anymore; my brain is letting me down..), and what specifically fascinated me was a research where they attached sensors on the "subject's" head, and asked this person all kinds of questions (and tests etc). It appeared that the sensors/computer already picked up activity in the specific part that was expected to solve that specific question, but the person was not yet aware of the fact that he/she already solved the question. The research suggested that the unconscious part of the brain already solved it, but that it yet had to boil up to the conscious brain. Fascinating stuff. Not sure whether my comment is completely on topic though. Thanks for the great article.

    • billybuc profile image

      Bill Holland 8 months ago from Olympia, WA

      What's really amazing is that many Americans don't use theirs. LOL

      Great science lesson, as always. I love this stuff, so thank you!

    • AliciaC profile image
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      Linda Crampton 8 months ago from British Columbia, Canada

      Thank you very much for the interesting comment, Buildreps. I remember reading about the research that you describe. It certainly is fascinating! The activity of the brain is so intriguing.

    • AliciaC profile image
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      Linda Crampton 8 months ago from British Columbia, Canada

      Hi, Bill. I appreciate your visit and comment, as always. I think that science is a very interesting topic.

    • Larry Rankin profile image

      Larry Rankin 8 months ago from Oklahoma

      Really interesting science history. Wonderfully informative.

    • AliciaC profile image
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      Linda Crampton 8 months ago from British Columbia, Canada

      Thank you very much, Larry. I appreciate your comment.

    • profile image

      manatita44 8 months ago

      An inspirational piece with very well-researched and sound knowledge. I was reading a little about Bruce Lee today. He feels that nothing is perfect, that there is and will always be scope for improvement. In this Light, I have no doubt that man will go further and yet further is this interesting study of the anatomy and indeed himself. Excellent Alicia.

    • AliciaC profile image
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      Linda Crampton 8 months ago from British Columbia, Canada

      Thank you, Manatita. I appreciate your kind comment and the interesting information about Bruce Lee. I like his idea!

    • Faith Reaper profile image

      Faith Reaper 8 months ago from southern USA

      Fascinating and well-written article on the amazing brain, Linda! Nothing man can ever come up with to come close to imitating the brain, even the most advanced computer in the world, nothing compares to the brain. This would fit nicely in my series, Our Amazing Bodies ... and I know I couldn't have covered the brain as well as you have here, no doubt!

      It is certainly amazing they are still discovering new areas of the brain.

      As always, I learned a lot once again.

      I hope you are enjoying a peaceful weekend.

    • AliciaC profile image
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      Linda Crampton 8 months ago from British Columbia, Canada

      Thank you for the lovely comment, Faith. I appreciate it very much! The human brain is definitely awesome. It has many very impressive and amazing abilities.

      I hope you're having a good weekend and that the week ahead is enjoyable for you.

    • profile image

      MsDora 7 months ago

      Alicia, thanks for this very informative lesson. I will save it as a reference article to read again.

    • AliciaC profile image
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      Linda Crampton 7 months ago from British Columbia, Canada

      Thank you very much, MsDora. I appreciate your visit a great deal.

    • profile image

      DDE 7 months ago

      Hi a fascinating subject and you presented in detail. A must read hub indeed.

    • teaches12345 profile image

      Dianna Mendez 7 months ago

      I enjoyed your post on the brain. I always learn so much from your sharing.

    • AliciaC profile image
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      Linda Crampton 7 months ago from British Columbia, Canada

      Hi, Devika. Thank you for the kind comment.

    • AliciaC profile image
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      Linda Crampton 7 months ago from British Columbia, Canada

      Thanks, Dianna. I appreciate your visit and comment, as I always do.

    • profile image

      Deb Hirt 6 months ago

      It will still take time to learn the functions of the complicated makeup of the brain, for it controls so much of our bodily functions. This was a wonderful and fascinating read.

    • AliciaC profile image
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      Linda Crampton 6 months ago from British Columbia, Canada

      Thank you for the comment, Deb. I appreciate it very much. I agree with you - it's going to take time to understand the brain in more detail. It's a complicated and amazing organ.

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