Whole Brain Teaching and Learning
by Sue Leonard
This article reviews the concepts of Ned Herrmann’s Brain Dominance theory and instrument. Herrmann’s Whole Brain Model can be used to build learning experiences to enhance learning and make it more memorable for all participants.
Ned Herrmann’s Research
Ned Herrman's Whole Brain Model combines Roger Sperry's left/right brain theory and Paul MacLean's triune model (rational brain, intermediate brain and primitive brain) to produce a quadrant model of the brain. The quadrants are:
Left Cerebral (upper left)
Left Limbic (lower left)
Right Limbic (lower right)
Right Cerebral (upper right
As with the other brain models, each area has functions associated it to create a model of thinking and learning. Practitioners of HBDT use the following labels each quadrant for persons whose strongest preference is in that quadrant:
Left Cerebral: Theorists
Left Limbic: Organizers
Right Limbic: Humanitarians
Right Cerebral: Innovators
Theorists: These are people who like lecture, facts, and details, critical thinking, textbooks and readings, etc. The brain dominance for theorists is the upper left (cerebral).
Organizers: These are people who prefer to learn by outlining, checklists, exercises and problem solving with steps, policies and procedures. People with these preferences have lower left (limbic) brain dominance.
Innovators: Innovators prefer brainstorming, metaphors, illustrations and pictures, mind mapping and synthesis, and holistic approaches. The brain dominance for innovators is upper right (cerebral).Humanitarians: Prefer cooperative learning and group discussion, role-playing, and dramatization. Their brain preference is lower right (limbic)
Preferred Learning Activities
Knowledge of HBDT can help people in the training and education fields develop and deliver training that is more applicable to everyone and is also better remembered. Each quadrant has a preferred style of learning and preferences for particular types of learning activities. When the activity matches a learner’s preference, there is an increased probability that learning will occur. Below are some activities with the HBDI preference that prefers that activity shown in parentheses:
Precise definitions (theorist)
To-the-point, factual learnings (theorist)
Step-by-step instructions (organizer)
History, timelines (organizer)
Brainstorming or free association activities (innovator)
Visual or graphic mind-maps (innovator)
Use of personal impact stories (humanist)
Collaborative activities (humanist)
Frustrations in Learning
When training is biased mostly toward one HBDI preference, persons with other preferences will experience a great deal of frustration. Participants can check out mentally when the training environment has too many of the frustrations for their HDBI preference. Below are some of the types of frustrations people can experience. The HBDI preference that might experience that frustration is shown in parentheses after the frustration:
Vague, ambiguous instructions (theorist)
Inefficient use of time (theorist)
Too slow a pace (innovator)
Lack of overview/conceptual framework (innovator)
Disorganization, poor sequencing, hopping around (organizer)
Lack of practice time (organizer)
Impersonal approach or examples (humanist)
No sensory input; sterile learning climate (humanist)
Teaching & Learning Assumptions
The Whole Brain teaching approach starts with several teaching and learning assumptions that are very consistent with MBTI principles:
People have different preferred modes of thinking and learning
Those preferences influence how we:
process and store information
retrieve information
make meaning out of information
All learning groups are made up of people with different thinking style preferences, different ways of knowing, and different learning styles.
Effective learning is “whole brained”, taking advantage of the all the mental processes of the brain
Teachers and trainers typically design learning experiences that reflect their own thinking/learning preferences.
In light of the above, we need to re-examine all of our previous assumptions about teaching and learning
The content, design and delivery of each learning point must be whole brained to meet the diverse learning and thinking styles of the learners. This is achieved by “paraphrasing” the learning point in each of the different modes of the whole brain model.
Herman International has designed a training kit that helps developers and trainers pick activities to ensure whole brain training. The kit has cards with several learning activities for each HBDI preference. The idea is that each learning module or segment should have activities for each quadrant’s preferences. One recommendation is to pick two activities for each quadrant.
So a balanced training might look like this:
Agenda (quadrant B)
Overview (quadrant D)
Warm-up (quadrant C)
Factual lecture (quadrant A)
Concrete examples (quadrant B)
Brainstorming or mind-mapping (quadrant D)
Critical review of material (quadrant A)
Journaling or stories (quadrant C)
When teaching, managing and communicating are going well, they are most likely whole-brained. They also noted that when things don’t seem to be working, it’s likely we’ve forgotten one or more of the quadrants.
Correlation Myers-Briggs Type Indicator ®
As Myers-Briggs Type Indicator (MBTI®) enthusiasts might speculate, there is a correlation between MBTI® preference and HBDI preference. Sally Power, Jean Kummerow and Lorman Lundsten (1999) conducted multiple studies based on some previous work done by Power and Lundsten (1997). Figure 2 shows the relationships. The results were mixed, with the strongest correlations between Introverted Thinking and Cerebral Left (theorists) and Extraverted iNtuition and Cerebral Right (innovators).
Group Preferences
THE HBDI has been given to over one million people. Hermann has discovered that in groups of 15 or more with ‘normal’ characteristics, the group will be spread among the four quadrants. However, brain dominance data also indicate that people with similar occupations tend to have the same general profile. Data also show there is a strong and direct correlation between a person’s personal profile and his or her occupational profile, and his or her learning profile. This shows that it is essential to consider the uniqueness of the learning group when designing educational programs for the group.
HBD Instrument
Hermann Developed an instrument, the Herrmann Brain Dominance Instrument™ (HBDI) in 1979. The HBDI™ is a thinking styles assessment tool which allows a person to learn more about how his or her brain functions and thinking and learning preferences. The HBDI™ is the result of extensive validation and has been developed and modified taking into account the results of continuing brain research. Three examples of the rigorous validation for the HBDI™ are:
Validation studies of C. Victor Bunderson and James Olsen of Wicat and later by C. Victor Bunderson and Kevin Ho. Schadty and Potvin at the University of Texas carried out validation experiments in conjunction with these validation studies.
Through the research and experimentation of leaders in the field including Roger Sperry, Robert Ornstein, Henry Mintzberg, and Michael Gazzaniga.
Hundreds of EEG experiments carried out by Ned Herrmann.
Other features of the HBDI include:
The results of the scoring are free of value judgment and cultural bias.
The HBDI is adaptable and takes account of the fact that we can grow and change. This encourages many people to discover and design a pathway for change.
References
Herrmann, Ned, The Creative Brain, Insights into creativity, communication, management, education and self-understanding, The Ned Herrmann Group, 1995.
Herrmann, Ned, The Whole Brain Business Book, New YorkMcGrtaw-Hill, 1996.
Power, Sally J. and Lundsten, Lorman, Studies That Compare Type Theory and Lef-Brain-Right-Brain Theory, Journal of Psychological Type, Vol 43, 1997.
Power, Sally J, Kummerow, Jean M. and Lundsten, Lorman, A Herrmann Brain Dominance Profile Analysis of the Sixteen MBTI Types In a Sample of MBA Students, Journal of Psychological Type, Vol 49, 1999.
Hermann International, The Ned Herrmann Group -- http://www.hbdi.com/
Dynamic Thinking: http://www.dynamicthinking.com/HBDI.htm
Hope Unlimited http://www.hopellc.com/bdsi.html
ACCSYS Corporation: FAQs: http://www.accsys-corp.com/HBDI_FAQ/hbdi_faq.html
Paul McLean’s Triune Model http://www.kheper.auz.com/gaia/intelligence/MacLean.htm
For more about whole-brain learning contact Leonard Consulting at 847-692-1911.
11/06/2007
10/04/2007
Various Tests
BEYOND MYERS-BRIGGS: THE ART OF USING YOUR WHOLE BRAIN Lya Sorano
This article first appeared in the Jan/Feb 2001 issue of Competitive Edge® magazine.
"The workshop had barely run 10 minutes, when the hunched-over woman in the blue dress in the front row raised her hand. “Is Myers-Briggs ever wrong?” With graphs and drawings plastered all over the walls and a standing-room only crowd in attendance, the facilitator had encouraged questions, but this one came too soon, too early on. Except that . . . it was such a good question! Others in the audience had wondered about this also, even if they had never voiced their doubts. Myers-Briggs, after all, is the widely-used, undisputed vehicle for personality testing, isn’t it? Companies use it all the time, to find out if a new hire should become a financial analyst or join the marketing team. Women who hire coaches for personal growth and development – such a nineties thing! – are routinely given the test and offered advice and encouragement based upon its results. Is Myers-Briggs ever wrong? How could that be possible?“Yes, yes,” the facilitator’s eyes lit up, her engaging smile became a beam and she was obviously thrilled with the interlocutor’s question, “and let me tell you why!”Based upon the groundbreaking work of Dr. Carl G. Jung, the Swiss psychiatrist who first developed a theory of psychological types and identified eight elements that became the tools for understanding, guiding and helping people, both the mother-daughter team of Myers and Briggs (in the 1950s), and Katherine Benziger, Ph.D. (in the 1990s) designed instruments for personality assessment. The difference between the two instruments (Myers-Briggs’s MBTI and Benziger’s BTSA) is that the former is based on only the first five of Jung’s elements, while the latter makes use of all eight. Dr. Jung developed his theory in the 1930s and had absolutely no interest in a popular/commercial application. Myers-Briggs had the application interest, but stopped short of the more complicated – and interesting! – science behind Jung’s theory. Then, thirty years after the MBTI was introduced, Dr. Benziger, a neuropsychologist by training, took the whole thing and designed her BTSA, which is now available for personal assessment as well as a workplace testing tool, both online and in print.Once you have an understanding of your preference, you will be able to use the guidelines provided in Thriving in Mind to help you lessen the extent to which you falsify type - by leveraging your preference consciously and frequently each day, and by consciously managing how you handle all tasks that require skills not managed by your preference.“The person who gave me the test,” the woman in blue continued, “told me I was an extravert and should think about a career in sales, but I know I am an introvert and I don’t think selling is my strong point.” “Myers-Briggs works very well,” the workshop leader commented, “if the person being tested thinks true to his or her type. But if type is falsified, the outcome of the test is often wrong.” Jung, Myers-Briggs and Benziger work with the same types of thinking: intuitive, thinking, feeling and sensing (Jung’s element 1); they also use the two established directions of focusing energy (introversion and extraversion: element 2). They agree that everyone has a dominant (preferred, lead) mode of thinking (element 3) and that this mode combines (Jung’s 4th element) with the focused energy direction to form a person’s personality type: the introverted thinker and the extraverted thinker, the introverted feeler and the extraverted feeler, the introverted intuitive and the extraverted intuitive, the introverted sensor and the extraverted sensor. Element 5 of Jung’s theory is described as “Living True to Type” – the extraverted thinker acts as an extraverted thinker, the introverted intuitive acts as an introverted intuitive, etc. – and this is where Myers-Briggs leaves us. Katherine Benziger, however, continued with elements 6, 7 and 8 of Jung’s theory (e.g. “Falsifying Type”, “The Cost of Falsification” and “Links between Living True to Type and Wellness on the one hand and Falsifying Type and Illness on the other”) and offers the world her BTSA assessment tool.The woman in the front row was much relieved, but others in the audience now had their hands up: “What do you mean by falsified type?” “What makes us falsify type?” “How do we know if we falsify type?”Briefly, this is what the workshop leader conveyed to her audience:
If, during the day, day in and day out, you mostly use your non-dominant, non-preferred mode of thinking most of the time, your mode of thinking is falsified, not natural, not true to your innate thinking type.
Conditioning causes us to set aside our natural thinking type and adopt a false one. The US educational system is geared towards the adoption of a falsified thinking type and our workplaces perpetuate the process.
There is a simple test. If you lack energy and enthusiasm, if you feel tired or depressed, if you are prone to illnesses, even minor ones, if you experience boredom at work or lack of “centeredness” at home, chances are you are falsifying your natural thinking type. Hungry for far more than the 90-minute workshop was able to provide, the facilitator referred her audience to Dr. Benziger’s Web site (www.benziger.org) and her book “Thriving in Mind” (order information available on the Web site). The woman in the blue dress left the room with a smile on her face and noticeably straightened shoulders, her Myers-Briggs experience explained and well put behind her. Now she knew how to get beyond its limitations".
This article first appeared in the Jan/Feb 2001 issue of Competitive Edge® magazine.
"The workshop had barely run 10 minutes, when the hunched-over woman in the blue dress in the front row raised her hand. “Is Myers-Briggs ever wrong?” With graphs and drawings plastered all over the walls and a standing-room only crowd in attendance, the facilitator had encouraged questions, but this one came too soon, too early on. Except that . . . it was such a good question! Others in the audience had wondered about this also, even if they had never voiced their doubts. Myers-Briggs, after all, is the widely-used, undisputed vehicle for personality testing, isn’t it? Companies use it all the time, to find out if a new hire should become a financial analyst or join the marketing team. Women who hire coaches for personal growth and development – such a nineties thing! – are routinely given the test and offered advice and encouragement based upon its results. Is Myers-Briggs ever wrong? How could that be possible?“Yes, yes,” the facilitator’s eyes lit up, her engaging smile became a beam and she was obviously thrilled with the interlocutor’s question, “and let me tell you why!”Based upon the groundbreaking work of Dr. Carl G. Jung, the Swiss psychiatrist who first developed a theory of psychological types and identified eight elements that became the tools for understanding, guiding and helping people, both the mother-daughter team of Myers and Briggs (in the 1950s), and Katherine Benziger, Ph.D. (in the 1990s) designed instruments for personality assessment. The difference between the two instruments (Myers-Briggs’s MBTI and Benziger’s BTSA) is that the former is based on only the first five of Jung’s elements, while the latter makes use of all eight. Dr. Jung developed his theory in the 1930s and had absolutely no interest in a popular/commercial application. Myers-Briggs had the application interest, but stopped short of the more complicated – and interesting! – science behind Jung’s theory. Then, thirty years after the MBTI was introduced, Dr. Benziger, a neuropsychologist by training, took the whole thing and designed her BTSA, which is now available for personal assessment as well as a workplace testing tool, both online and in print.Once you have an understanding of your preference, you will be able to use the guidelines provided in Thriving in Mind to help you lessen the extent to which you falsify type - by leveraging your preference consciously and frequently each day, and by consciously managing how you handle all tasks that require skills not managed by your preference.“The person who gave me the test,” the woman in blue continued, “told me I was an extravert and should think about a career in sales, but I know I am an introvert and I don’t think selling is my strong point.” “Myers-Briggs works very well,” the workshop leader commented, “if the person being tested thinks true to his or her type. But if type is falsified, the outcome of the test is often wrong.” Jung, Myers-Briggs and Benziger work with the same types of thinking: intuitive, thinking, feeling and sensing (Jung’s element 1); they also use the two established directions of focusing energy (introversion and extraversion: element 2). They agree that everyone has a dominant (preferred, lead) mode of thinking (element 3) and that this mode combines (Jung’s 4th element) with the focused energy direction to form a person’s personality type: the introverted thinker and the extraverted thinker, the introverted feeler and the extraverted feeler, the introverted intuitive and the extraverted intuitive, the introverted sensor and the extraverted sensor. Element 5 of Jung’s theory is described as “Living True to Type” – the extraverted thinker acts as an extraverted thinker, the introverted intuitive acts as an introverted intuitive, etc. – and this is where Myers-Briggs leaves us. Katherine Benziger, however, continued with elements 6, 7 and 8 of Jung’s theory (e.g. “Falsifying Type”, “The Cost of Falsification” and “Links between Living True to Type and Wellness on the one hand and Falsifying Type and Illness on the other”) and offers the world her BTSA assessment tool.The woman in the front row was much relieved, but others in the audience now had their hands up: “What do you mean by falsified type?” “What makes us falsify type?” “How do we know if we falsify type?”Briefly, this is what the workshop leader conveyed to her audience:
If, during the day, day in and day out, you mostly use your non-dominant, non-preferred mode of thinking most of the time, your mode of thinking is falsified, not natural, not true to your innate thinking type.
Conditioning causes us to set aside our natural thinking type and adopt a false one. The US educational system is geared towards the adoption of a falsified thinking type and our workplaces perpetuate the process.
There is a simple test. If you lack energy and enthusiasm, if you feel tired or depressed, if you are prone to illnesses, even minor ones, if you experience boredom at work or lack of “centeredness” at home, chances are you are falsifying your natural thinking type. Hungry for far more than the 90-minute workshop was able to provide, the facilitator referred her audience to Dr. Benziger’s Web site (www.benziger.org) and her book “Thriving in Mind” (order information available on the Web site). The woman in the blue dress left the room with a smile on her face and noticeably straightened shoulders, her Myers-Briggs experience explained and well put behind her. Now she knew how to get beyond its limitations".
1/11/2007
For our basal left friends (green) a bit of history on brain study
History of the brain
From Wikipedia, the free encyclopedia
The history of the brain details the development of thoughts, speculations, and ideas as to the function of the central nervous system, over the last five-thousand years.
Early views on the function of the brain, regarded it to be a form of “cranial stuffing” of sorts. In Egypt, from the late Middle Kingdom onwards, in preparation for mummification, the brain was regularly removed, for it was the heart that was assumed to be the seat of intelligence. According to Herodotus, during the first step of mummification: ‘The most perfect practice is to extract as much of the brain as possible with an iron hook, and what the hook cannot reach is mixed with drugs.’ Over the next five-thousand years, this view came to be reversed; the brain is now known to be seat of intelligence, although colloquial variations of the former remain as in “memorizing something by heart”.
Earliest views
Hieroglyphic for the word "brain" (c.1700 BC)
The Edwin Smith Surgical Papyrus, written in the 17th century BC, contains the earliest recorded reference to the brain. The word brain (adjacent), occurring eight times in this papyrus, describes the symptoms, diagnosis, and prognosis of two patients, wounded in the head, who had compound fractures of the skull.[1]
During the second half of the first millennium BC, the Ancient Greeks developed differing views on the function of the brain. It is said that it was the pythagorean Alcmaeon of Croton (VI and V centuries BC) who first considered the brain to be the place where the mind was located. In the 4th BC Hippocrates, believed the brain to be the seat of intelligence (based, among others before him, on Alcmeon's work). During the 4th century BC Aristotle though that, while the heart was the seat of intelligence, the brain was a cooling mechanism for the blood . He reasoned that humans are more rational than the beasts because, among other reasons, they have a larger brain to cool their hot-bloodedness [2]. During the hellenistic period, Herophilus of Calcedonia (c.335/330-280/250 BC) and Erasistratus of Ceos (c. 300-240 BC) made fundamental contributions not only to brain and nervous systems' anatomy and physiology, but to almost every field of the bio-sciences. Their works are today almost completely lost, we know about their achievements due mostly to secondary sources. Their discoveries had to be re-discovered two millenia after their death.
Drawing of the base of the brain by Andrea Vesalius (1543).
During the Roman Empire, the greek anatomist Galen dissected the brains of sheep, monkeys, dogs, swine, among other non-human mammals. He concluded that, as the cerebellum was more dense than the brain, it must control the muscles, while as the cerebrum was soft, it must be where the senses were processed. Galen further theorized that the brain functioned by movement of fluids through the ventricles[3].
1600s
In the Age of Enlightenment, René Descartes espoused a fluid mechanical view of the brain similar to Galen's. However, Descartes thought that although this explanation was adequate for the brain functions of animals, the higher mental functions of humans were accomplished by the "soul". This theoretical separation of the mind and brain became known as the mind-body problem, with Descartes espousing the dualist view of the mind as separate from the brain[4].
In the mid-1600s great progress in describing the anatomy of the brain (neuroanatomy) was achieved by the English anatomist Thomas Willis and Flemish anatomist Vesalius. They dispelled many of the notions of Galen and Descartes, and resolved many facts about the macro structure of the brain.
1700s
In the 1700s, Luigi Galvani showed that electrically stimulating the sciatic nerve of a dissected frog caused movement of the attached muscle. His experiments moved scientists away from the fluid mechanical theory of the brain and toward an electrical theory. In the 19th century, Galvani's work led to research in bioelectricity and to the discovery of the membrane potential and action potential by researchers such as Emil du Bois-Reymond.
1800s
The scientists of the 1800s debated whether areas of the brain corresponded to specific functions or if the brain functioned as a whole (the "aggregate field theory"). Jean Pierre Flourens championed the aggregate field theory in opposition to the pseudoscience of phrenology, founded by Franz Joseph Gall. However, the work of Paul Broca, Karl Wernicke, and Korbinian Brodmann eventually helped to show that areas of the brain had specific functions. Their work showed that, while some functions were repeated, there is also a lateralization of brain function whereby some functions, such as speech and language, are usually controlled by a particular cerebral hemisphere. The redundancy of functioning has come to be known as parallel distributed processing [5].
1900s
First EEG trace recorded by Hans Berger (1929)
By the 20th century, the anatomical works of Santiago Ramón y Cajal and Camillo Golgi laid the foundation for the study of individual neurons. Charles Scott Sherrington and Edgar Douglas Adrian furthered the study of neurons with the new techniques using electrodes. Neurotransmitters were discovered and investigated by many scientists, including Otto Loewi, Henry Hallett Dale, and Arvid Carlsson. These neurochemicals are responsible for carrying signals from one neuron to another across the tiny gaps (synapses) between the neuronal connections.
In 1929, German physician Hans Berger recorded the first electrical potentials from a living brain. This technique—known as electroencephalography or EEG—led to the widespread use of neuroimaging on live, active humans and animals to study the processes of the mind.
Modern neuroscience is experiencing rapid growth due to the availability of computers capable of handling the intense processing required for understanding such a complex system. Neuroscientists use many different approaches to study the brain at different levels—from the molecules to systems. Considerable knowledge has accumulated about the electrophysiological properties of different types of neurons and their responses to neurotransmitters. Recordings from the brains of awake, behaving animals pioneered by Edward Evarts help to decode neuronal firing during different behaviors and cognitive processes. Miguel Nicolelis introduced multi-electrode recording techniques which led to creation of rudimentary brain-computer interfaces. Rapidly developing neuroimaging techniques such as functional magnetic resonance imaging (fMRI) allows scientists to study the brain in living humans and animals in ways that their predecessors could not.
References
↑ Bear, M.F.; B.W. Connors, and M.A. Paradiso (2001). Neuroscience: Exploring the Brain. Baltimore: Lippincott. ISBN 0-7817-3944-6.
↑ Kandel, ER; Schwartz JH, Jessell TM (2000). Principles of Neural Science, 4th ed., New York: McGraw-Hill. ISBN 0-8385-7701-6.
From Wikipedia, the free encyclopedia
The history of the brain details the development of thoughts, speculations, and ideas as to the function of the central nervous system, over the last five-thousand years.
Early views on the function of the brain, regarded it to be a form of “cranial stuffing” of sorts. In Egypt, from the late Middle Kingdom onwards, in preparation for mummification, the brain was regularly removed, for it was the heart that was assumed to be the seat of intelligence. According to Herodotus, during the first step of mummification: ‘The most perfect practice is to extract as much of the brain as possible with an iron hook, and what the hook cannot reach is mixed with drugs.’ Over the next five-thousand years, this view came to be reversed; the brain is now known to be seat of intelligence, although colloquial variations of the former remain as in “memorizing something by heart”.
Earliest views
Hieroglyphic for the word "brain" (c.1700 BC)
The Edwin Smith Surgical Papyrus, written in the 17th century BC, contains the earliest recorded reference to the brain. The word brain (adjacent), occurring eight times in this papyrus, describes the symptoms, diagnosis, and prognosis of two patients, wounded in the head, who had compound fractures of the skull.[1]
During the second half of the first millennium BC, the Ancient Greeks developed differing views on the function of the brain. It is said that it was the pythagorean Alcmaeon of Croton (VI and V centuries BC) who first considered the brain to be the place where the mind was located. In the 4th BC Hippocrates, believed the brain to be the seat of intelligence (based, among others before him, on Alcmeon's work). During the 4th century BC Aristotle though that, while the heart was the seat of intelligence, the brain was a cooling mechanism for the blood . He reasoned that humans are more rational than the beasts because, among other reasons, they have a larger brain to cool their hot-bloodedness [2]. During the hellenistic period, Herophilus of Calcedonia (c.335/330-280/250 BC) and Erasistratus of Ceos (c. 300-240 BC) made fundamental contributions not only to brain and nervous systems' anatomy and physiology, but to almost every field of the bio-sciences. Their works are today almost completely lost, we know about their achievements due mostly to secondary sources. Their discoveries had to be re-discovered two millenia after their death.
Drawing of the base of the brain by Andrea Vesalius (1543).
During the Roman Empire, the greek anatomist Galen dissected the brains of sheep, monkeys, dogs, swine, among other non-human mammals. He concluded that, as the cerebellum was more dense than the brain, it must control the muscles, while as the cerebrum was soft, it must be where the senses were processed. Galen further theorized that the brain functioned by movement of fluids through the ventricles[3].
1600s
In the Age of Enlightenment, René Descartes espoused a fluid mechanical view of the brain similar to Galen's. However, Descartes thought that although this explanation was adequate for the brain functions of animals, the higher mental functions of humans were accomplished by the "soul". This theoretical separation of the mind and brain became known as the mind-body problem, with Descartes espousing the dualist view of the mind as separate from the brain[4].
In the mid-1600s great progress in describing the anatomy of the brain (neuroanatomy) was achieved by the English anatomist Thomas Willis and Flemish anatomist Vesalius. They dispelled many of the notions of Galen and Descartes, and resolved many facts about the macro structure of the brain.
1700s
In the 1700s, Luigi Galvani showed that electrically stimulating the sciatic nerve of a dissected frog caused movement of the attached muscle. His experiments moved scientists away from the fluid mechanical theory of the brain and toward an electrical theory. In the 19th century, Galvani's work led to research in bioelectricity and to the discovery of the membrane potential and action potential by researchers such as Emil du Bois-Reymond.
1800s
The scientists of the 1800s debated whether areas of the brain corresponded to specific functions or if the brain functioned as a whole (the "aggregate field theory"). Jean Pierre Flourens championed the aggregate field theory in opposition to the pseudoscience of phrenology, founded by Franz Joseph Gall. However, the work of Paul Broca, Karl Wernicke, and Korbinian Brodmann eventually helped to show that areas of the brain had specific functions. Their work showed that, while some functions were repeated, there is also a lateralization of brain function whereby some functions, such as speech and language, are usually controlled by a particular cerebral hemisphere. The redundancy of functioning has come to be known as parallel distributed processing [5].
1900s
First EEG trace recorded by Hans Berger (1929)
By the 20th century, the anatomical works of Santiago Ramón y Cajal and Camillo Golgi laid the foundation for the study of individual neurons. Charles Scott Sherrington and Edgar Douglas Adrian furthered the study of neurons with the new techniques using electrodes. Neurotransmitters were discovered and investigated by many scientists, including Otto Loewi, Henry Hallett Dale, and Arvid Carlsson. These neurochemicals are responsible for carrying signals from one neuron to another across the tiny gaps (synapses) between the neuronal connections.
In 1929, German physician Hans Berger recorded the first electrical potentials from a living brain. This technique—known as electroencephalography or EEG—led to the widespread use of neuroimaging on live, active humans and animals to study the processes of the mind.
Modern neuroscience is experiencing rapid growth due to the availability of computers capable of handling the intense processing required for understanding such a complex system. Neuroscientists use many different approaches to study the brain at different levels—from the molecules to systems. Considerable knowledge has accumulated about the electrophysiological properties of different types of neurons and their responses to neurotransmitters. Recordings from the brains of awake, behaving animals pioneered by Edward Evarts help to decode neuronal firing during different behaviors and cognitive processes. Miguel Nicolelis introduced multi-electrode recording techniques which led to creation of rudimentary brain-computer interfaces. Rapidly developing neuroimaging techniques such as functional magnetic resonance imaging (fMRI) allows scientists to study the brain in living humans and animals in ways that their predecessors could not.
References
↑ Bear, M.F.; B.W. Connors, and M.A. Paradiso (2001). Neuroscience: Exploring the Brain. Baltimore: Lippincott. ISBN 0-7817-3944-6.
↑ Kandel, ER; Schwartz JH, Jessell TM (2000). Principles of Neural Science, 4th ed., New York: McGraw-Hill. ISBN 0-8385-7701-6.
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