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Archive for June 2008

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Written by Joseph Eulo

June 13, 2008 at 10:06 pm

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Past, Present, and Promise (Video 1)

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Past, Present, and Promise is the first program in the DISCOVERING PSYCHOLOGY series. It provides an introduction to and overview of psychology, from its origins in the nineteenth century to current study of the brain’s biochemistry. You’ll explore the development of psychology in general and some of the paths scientists take to determine relationships among the mind, the brain, and behavior.

Psychology is defined as the scientific study of the behavior of individuals and their mental processes. Like many sciences, psychology has evolved with technology, giving doctors and researchers new tools to measure human behavior and analyze its causes.

In this program, Dr. Mahzarin Banaji from Yale University uses the Implicit Association Test (IAT) to measure how quickly positive or negative values are associated with white or black faces. Her subjects are shown a series of words and pictures and instructed to respond immediately by pushing a button to indicate their most automatic, reflex-like reactions. For example, they may be told to press a button in their right hand if the automatic association is good and to press a button in their left hand if the association is bad. The speed with which the subjects respond is an important element of the experiment because these quick, unconscious connections can reveal biases that differ from conscious beliefs.

The IAT results are matched against functional Magnetic Resonance Imaging (fMRI) data to track activity in the amygdala, the region of the brain that responds to fearful or negative images. By correlating data on the buttons subjects pushed with fMRI information about activity in the amygdala, Dr. Banaji and her colleagues have found some interesting results. The majority of the white American respondents showed an unconscious association of white with good and black with bad, while the African American respondents showed mixed results. Half more quickly associated black with good, and the other half associated white with good.

Tracking brain activity in controlled experiments reveals not only the region of the brain at work, but also the power of images and messages in our culture on the subconscious human psyche, bringing psychologists one step closer to understanding human behavior. Read the rest of this entry »

Written by Joseph Eulo

June 8, 2008 at 2:55 am

The Human Brain

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Your brain can be considered the most complex organ in your body and the
centerpiece of your nervous system. Although your brain works as a
unified whole, neuroscientists can identify areas within it that
perform specific functions. Your brain is organized into three
interconnected layers: the central core, limbic system, and cerebral cortex, all of which contain structures that regulate everyday life. Explore the human brain and its role in regulating your life.

The Brain

Written by Joseph Eulo

June 8, 2008 at 2:44 am

History of Psychology

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1879

 First psychology laboratory
Wilhelm Wundt opens first experimental laboratory in psychology at the
University of Leipzig, Germany. Credited with establishing psychology
as an academic discipline, Wundt’s students include Emil Kraepelin,
James McKeen Cattell, and G. Stanley Hall.

1883

 First American psychology laboratory
G. Stanley Hall, a student of Wilhelm Wundt, establishes first U.S.
experimental psychology laboratory at Johns Hopkins University.

1886

 First doctorate in psychology
The first doctorate in psychology is given to Joseph Jastrow, a student
of G. Stanley Hall at Johns Hopkins University. Jastrow later becomes
professor of psychology at the University of Wisconsin and serves as
president of the American Psychological Association in 1900.

1888

 First professor of psychology
The academic title “professor of psychology” is given to James McKeen
Cattell in 1888, the first use of this designation in the United
States. A student of Wilhelm Wundt’s, Cattell serves as professor of
psychology at University of Pennsylvania and Columbia University.

1892

 APA founded
G. Stanley Hall founds the American Psychological Association (APA) and
serves as its first president. He later establishes two key journals in
the field: American Journal of Psychology (1887) and Journal of Applied
Psychology (1917).

1896

 Functionalism
Functionalism, an early school of psychology, focuses on the acts and
functions of the mind rather than its internal contents. Its most
prominent American advocates are William James and John Dewey, whose
1896 article “The Reflex Arc Concept in Psychology” promotes
functionalism.Psychoanalysis
The founder of psychoanalysis, Sigmund Freud, introduces the term in a
scholarly paper. Freud’s psychoanalytic approach asserts that people
are motivated by powerful, unconscious drives and conflicts. He
develops an influential therapy based on this assertion, using free
association and dream analysis.

Structuralism
Edward B. Titchener, a leading proponent of structuralism, publishes
his Outline of Psychology. Structuralism is the view that all mental
experience can be understood as a combination of simple elements or
events. This approach focuses on the contents of the mind, contrasting
with functionalism.

  First psychology clinic
After heading a laboratory at University of Pennsylvania, Lightner
Witmer opens world’s first psychological clinic to patients, shifting
his focus from experimental work to practical application of his
findings.

1900

 Interpretation of Dreams
Sigmund Freud introduces his theory of psychoanalysis in The Interpretation of Dreams,
the first of 24 books he would write exploring such topics as the
unconscious, techniques of free association, and sexuality as a driving
force in human psychology.

1901

 Manual of Experimental Psychology
With publication of the Manual of Experimental Psychology,
Edward Bradford Titchener introduces structuralism to the United
States. Structuralism, an approach which seeks to identify the basic
elements of consciousness, fades after Titchener’s death in 1927.

1904

 First woman president of the APA
Mary Calkins is elected president of the APA. Calkins, a professor and
researcher at Wellesley College, studied with William James at Harvard
University, but Harvard denied her a Ph.D. because of her gender.

1905

 IQ tests developed
Using standardized tests, Alfred Binet and Theodore Simon develop a
scale of general intelligence on the basis of mental age. Later
researchers refine this work into the concept of intelligence quotient;
IQ, mental age over physical age. From their beginning, such tests’
accuracy and fairness are challenged.

1908

 A Mind That Found Itself
Clifford Beers publishes A Mind That Found Itself,
detailing his experiences as a patient in 19th-century mental asylums.
Calling for more humane treatment of patients and better education
about mental illness for the general population, the book inspires the
mental hygiene movement in the United States.

1909

 Psychoanalysts visit Clark University
Sigmund Freud and Carl Jung visit the United States for a
Psychoanalysis Symposium at Clark University organized by G. Stanley
Hall. At the symposium, Freud gives his only speech in the United
States.

1913

 Behaviorism
John B. Watson publishes “Psychology as Behavior,” launching
behaviorism. In contrast to psychoanalysis, behaviorism focuses on
observable and measurable behavior.

1917

 Army intelligence tests implemented
Standardized intelligence and aptitude tests are administered to two
million U. S. soldiers during WWI. Soon after, such tests are used in
all U.S. armed forces branches and in many areas of civilian life,
including academic and work settings.

1920

 First African American doctorate in psychology
Francis Cecil Sumner earns a Ph.D. in psychology under G. Stanley Hall
at Clark University. Sumner later serves as chair of the Howard
University psychology department.
 The Child’s Conception of the World
Swiss psychologist Jean Piaget publishes The Child’s Conception of the World, prompting the study of cognition in the developing child.

1921

 Rorschach test created
Swiss psychiatrist Hermann Rorschach devises a personality test based on patients’ interpretations of inkblots.

1925

 Menninger Clinic founded
Charles Frederick Menninger and his sons Karl Augustus and William
Clair found The Menninger Clinic in Topeka, Kansas. They take a
compassionate approach to the treatment of mental illness, emphasizing
both psychological and psychiatric disciplines.

1927

 Menninger Clinic founded
First Nobel Prize for psychological research

1929

 Electroencephalogram invented
Psychiatrist Hans Berger invents the electroencephalogram and tests it
on his son. The device graphs the electrical activity of the brain by
means of electrodes attached to the head.

1933

 Nazi persecution of psychologists
After the Nazi party gains control of the government in Germany,
scholars and researchers in psychology and psychiatry are persecuted.
Many, including Freud, whose books are banned and burned in public
rallies, move to Britain or the United States.

1935

 Alcoholics Anonymous
Alcoholics Anonymous (AA) is founded by Bob Smith of Akron, Ohio. AA’s
group meetings format and 12-step program become the model for many
other mutual-support therapeutic groups.
 Gestalt psychology
Kurt Koffka, a founder of the movement, publishes Principles of Gestalt
Psychology in 1935. Gestalt (German for “whole” or “essence”)
psychology asserts that psychological phenomena must be viewed not as
individual elements but as a coherent whole.

1936

 First lobotomy in the United States
Walter Freeman performs first frontal lobotomy in the United States at
George Washington University in Washington, D.C. By 1951, more than
18,000 such operations have been performed. The procedure, intended to
relieve severe and debilitating psychosis, is controversial.

1937

 The Neurotic Personality of Our Time
Psychologist Karen Horney publishes The Neurotic Personality of Our Time.
Horney goes on to challenge many of Freud’s theories, as have many
later psychologists and scholars. Specifically, she questions Freud’s
theories on the Oedipal Complex and castration anxiety.

1938

 The Behavior of Organisms
B.F. Skinner publishes The Behavior of Organisms,
introducing the concept of operant conditioning. The work draws
widespread attention to behaviorism and inspires laboratory research on
conditioning.
 Electroconvulsive therapy begun
Italian psychiatrist and neuropathologist Ugo Cerletti and his
associates treat human patients with electrical shocks to alleviate
schizophrenia and psychosis. ECT, while controversial, is proven
effective in some cases and is still in use in 2001.

1946

 The Psychoanalytic Treatment of Children
Anna Freud publishes The Psychoanalytic Treatment of Children,
introducing basic concepts in the theory and practice of child
psychoanalysis.
 National Mental Health Act Passed
U.S. President Harry Truman signs the National Mental Health Act,
providing generous funding for psychiatric education and research for
the first time in U.S. history. This act leads to the creation in 1949
of the National Institute of Mental Health (NIMH).

1951

 First drug to treat depression
Studies are published reporting that the drug imipramine may be able to
lessen depression. Eight years later, the FDA approves its use in the
United States under the name Tofranil.

1952

 Thorazine tested
The anti-psychotic drug chlorpromazine (known as Thorazine) is tested
on a patient in a Paris military hospital. Approved for use in the
United States in 1954, it becomes widely prescribed.

1953

 APA Ethical Standards
The American Psychological Association publishes the first edition of Ethical Standards of Psychologists. The document undergoes continuous review and is now known as APA’s Ethical Principles of Psychologists and Code of Conduct.

1954

 Epilepsy and the Functional Anatomy…
In Epilepsy and the Functional Anatomy of the Human Brain,
neurosurgeon Wilder G. Penfield publishes results from his study of the
neurology of epilepsy. His mapping of the brain’s cortex sets a
precedent for the brain-imaging techniques that become critical to
biopsychology and cognitive neuroscience.
  The Nature of Prejudice
Social Psychologist Gordon Allport publishes The Nature of Prejudice,
which draws on various approaches in psychology to examine prejudice
through different lenses. It is widely read by the general public and
influential in establishing psychology’s usefulness in understanding
social issues.
 Biopsychology
In his studies of epilepsy, neuroscientist Wilder G. Penfield begins to
uncover the relationship between chemical activity in the brain and
psychological phenomena. His findings set the stage for widespread
research on the biological role in psychological phenomena.
  Psychopharmacology
The development of psychoactive drugs in the 1950s and their approval
by the FDA initiates a new form of treatment for mental illness. Among
the first such drugs is Doriden, also known as Rorer, an anti-anxiety
medication approved in 1954.
  Humanistic Psychology
In the wake of psychoanalysis and behaviorism, humanistic psychology
emerges as the “third force” in psychology. Led by Carl Rogers and
Abraham Maslow, who publishes Motivation and Personality in 1954, this
approach centers on the conscious mind, free will, human dignity, and
the capacity for self-actualization.

1956

 Cognitive psychology
Inspired by work in mathematics and other disciplines, psychologists
begin to focus on cognitive states and processes. George A. Miller’s
1956 article “The Magical Number Seven, Plus or Minus Two” on
information processing is an early application of the cognitive
approach.

1957

 Syntactic Structures
Noam Chomsky publishes Syntactic Structures,
marking a major advancement in the study of linguistics. The book helps
spawn the field of psycholinguistics, the psychology of language.

1960

 FDA approves Librium
The FDA approves the use of chlordiazepoxide (known as Librium) for
treatment of non-psychotic anxiety in 1960. A similar drug, diazepam
(Valium), is approved in 1963.

1963

 Community Mental Health Centers Act passed
U.S. President John F. Kennedy calls for and later signs the Community
Mental Health Centers Act, which mandates the construction of community
facilities instead of large, regional mental hospitals. Congress ends
support for the program in 1981, reducing overall funds and folding
them into a mental health block-grant program.

1964

 First National Medal of Science to psychologist
Neal E. Miller receives the National Medal of Science, the highest
scientific honor given in the United States, for his studies of
motivation and learning. He is the first psychologist to be awarded
this honor.

1964

 FDA approves Lithium
The FDA approves lithium carbonate to treat patients with bipolar mood
disorders. It is marketed under the trade names Eskalith, Lithonate,
and Lithane.

1973

 Homosexuality removed from DSM
After intense debate, the American Psychiatric Association removes
homosexuality from the Diagnostic and Statistical Manual of Mental
Disorders (DSM). The widely used reference manual is revised to state
that sexual orientation “does not necessarily constitute a psychiatric
disorder.”

1974

 PET scanner tested
A new brain scanning technique, Positron Emission Tomography (PET), is
tested. By tracing chemical markers, PET maps brain function in more
detail than earlier techniques.

1976

 Evolutionary psychology
Richard Dawkins publishes The Selfish Gene, which begins to popularize
the idea of evolutionary psychology. This approach applies principles
from evolutionary biology to the structure and function of the human
brain. It offers new ways of looking at social phenomena such as
aggression and sexual behavior.
 The Selfish Gene
Richard Dawkins publishes The Selfish Gene,
a work which shifts focus from the individual animal as the unit of
evolution to individual genes themselves. The text popularizes the
field of evolutionary psychology, in which knowledge and principles
from evolutionary biology are applied in research on human brain
structure.

1979

 Standardized IQ tests found discriminatory
The U.S. District Court finds the use of standardized IQ tests in
California public schools illegal. The decision in the case, Larry P.
v. Wilson Riles, upholds the plaintiff’s position that the tests
discriminate against African American students.

1981

 AIDS and HIV first diagnosed
The epidemic of acquired immunodeficiency syndrome (AIDS) and human
immunodeficiency virus (HIV) infection presents mental health
professionals with challenges ranging from at-risk patients’ anxiety
and depression to AIDS-related dementia.

1984

 Insanity Defense Reform Act passed
U.S. Congress revises federal law on the insanity defense, partly in
response to the acquittal of John Hinckley, Jr. of charges of attempted
assassination after he had shot President Ronald Reagan. The act places
burden of proof for the insanity defense on the defendant.

1987

 Homeless Assistance Act passed
The Stewart B. McKinney Homeless Assistance Act provides the first
federal funds allocated specifically for the homeless population. The
act includes provisions for mental health services, and responds, in
part, to psychological studies on homelessness and mental disorders.
 Prozac, Paxil, and Zoloft made available
The FDA approves the new anti-depressant medication fluoxetine,
(Prozac). The drug, and other similar medications, acts on
neurotransmitters, specifically, serotonin. It is widely prescribed and
attracts attention and debate.

1990

 Cultural psychology
In Acts of Meaning, Four Lectures on Mind and Culture, Jerome Bruner
helps formulate cultural psychology, an approach drawing on philosophy,
linguistics, and anthropology. Refined and expanded by Hazel Markus and
other researchers, cultural psychology focuses on the influences and
relationship among mind, cultural community and behavior.

2000

 Sequencing of the Human Genome
Sixteen public research institutions around the world complete a
“working draft” mapping of the human genetic code, providing a research
basis for a new understanding of human development and disease. A
similar, privately funded, project is currently underway.
 DSM on PDA
The latest revision of the Diagnostic Statistical Manual of Mental
Disorders (DSM) is published in a version for personal digital
assistants (PDAs). The manual, first published in 1954, outlines
prevalence, diagnosis, and treatment of mental disorders. Only 132
pages on first printing, in 2000 it was 980 pages.

Understanding Research (Video 2)

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Understanding Research is the second program in the DISCOVERING PSYCHOLOGY series. This program examines how we know what we know. You’ll explore the scientific method, the distinction between fact and theory, and the different ways in which data are collected and applied, both in labs and in real-world settings.

Research often begins with a question. Traditionally, answers have been found in lab experiments, surveys, test groups, and interviews.

This program provides an example of research in a field setting. Psychologist Dr. Christina Maslach of the University of California at Berkeley studies job burnout, what causes it, and what can be done to prevent it. Instead of using traditional lab settings, Dr. Maslach conducts her research where the burnout is happening, in the workplace, using a real-world setting as a lab.

By taking this “fly-on-the-wall” approach, Dr. Maslach studies stress as it occurs, relying on subjects’ live experiences rather than just their memories or perceptions of past experiences. In this case, she has developed a scale to measure job burnout and a scale to measure the health of the workplace environment. Scientific methods to ensure accuracy are part of her approach. She collects data from carefully controlled measurements and observations, and the research process is methodical. The experiment can then be reproduced and the data tested by other researchers. By sharing data through publishing results, psychologists provide new understandings and new tools, as well as fodder for new questions and debates.

Through this consistent, long-term work, Dr. Maslach’s research has shed light not only on individual employees’ behavior, but also on the behavior of an entire organization. The application of this research helps individuals develop mechanisms for coping with stress, and assists organizations in evaluating the health and effectiveness of the workplace.

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Written by Joseph Eulo

June 8, 2008 at 2:22 am

The Behaving Brain (Video 3)

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The Behaving Brain is the third program in the DISCOVERING PSYCHOLOGY series. This program looks at the structure and composition of the human brain: how neurons function, how information is collected and transmitted, and how chemical reactions relate to thought and behavior.

The human brain is an extraordinarily complex organ made up of different regions and parts, each with its own function. Chemical molecules and electrical impulses constantly flow between regions of the brain, sending signals and messages to other parts of the brain and body. Much like an orchestra, brain functioning depends on many individual parts working together.

One example highlighted in this program is the brain’s role in our ability to remember. Psychologist Dr. Mieke Verfaellie studies the causes and effects of amnesia at the Memory Disorders Research Center in Boston. Her research draws on evidence of damage to the hippocampal region of the brain, the area responsible for laying down new memories.

Contrary to popular opinion, amnesia doesn’t result in the loss of all memory or identity. Amnesia affects our short-term, or anteograde memory, and our ability to learn and retain new information. What’s interesting and often surprising in amnesia cases is that other regions of the brain continue to function normally, such as long-term memory. But damage to even one area, such as short-term memory, can dramatically affect our ability to navigate through daily life.

Neuroscientists are learning from abnormal brain functioning, such as amnesia, to identify normal brain patterns. For instance, the interplay of brain regions and their role in thoughts, understanding, and behavior are now better understood.

For a more detailed breakdown of the human brain, go to the Brain Exploration feature of this site.

Dr. Verfaellie contributed to an article about memory distortions in amnesic patients, published in MIT’s Journal of Cognitive Neuroscience, “When True Recognition Suppresses False Recognition: Evidence from Amnesic Patients.” http://mitpress.mit.edu/journals/JOCN/jcn10602.pdf.

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Written by Joseph Eulo

June 8, 2008 at 1:30 am

The Responsive Brain (Video 4)

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T

he Responsive Brain is the fourth program in the DISCOVERING PSYCHOLOGY series. This program explores how the brain alters its structure and functioning in response to social situations. You’ll learn about the impact of different stimuli on human and animal brains, from the effect of human touch on premature babies to the effect of social status on the health of baboons.

Dr. Russell Fernald is a neuroethologist at Stanford University. Neuroethology integrates brain science with the study of behavior in natural habitats. The goal is to illustrate the interaction among brain, behavior, and environment. Dr. Fernald’s long-term work focuses on the African cichlid fish and how its social system regulates not only brain structures, but also bodily functions.

When a male cichlid fish recognizes an opportunity to become the dominant male, his body turns bright colors. The male fish then chases and attacks other male cichlid fish in an attempt to dominate and defend his territory. The physiological color change results from a response in the hypothalamus in the brain. In the cichlid fish, the signaling peptide cells grow eight times larger, sending the brain eight times the signal. The result is an enlargement of the fish gonads, physiologically preparing the fish to spawn with females.

When the cichlid fish loses control of the territory, he loses his bright coloring. Some fish, however, will then go into hiding, turn on the color signals of dominance, and pretend that they are still dominant for a period lasting up to three weeks.

The human brain also contains the hypothalamus. Neuroethologists hypothesize that behavioral responses parallel to those cichlid fish take place in humans, beginning at puberty. Dr. Fernald’s research illustrates one example of how animal and human brains receive and translate signals from the social environment, resulting in physiological change.

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Written by Joseph Eulo

June 8, 2008 at 1:29 am

The Developing Child (Video 5)

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The Developing Child is the fifth program in the DISCOVERING PSYCHOLOGY series. This program introduces examples of cognitive, perceptual, and behavioral development in children. You’ll explore the roles of heredity and environment in child development, and children’s incremental understanding of such phenomena as object permanence, symbolic reasoning, and perception of visual depth.

One of the most distinctive human characteristics is the ability to understand and use symbols. We have a variety of symbol systems in our everyday lives. We use language, we read, we use pictures, and we understand computer programs. We’re not born with this ability, so what I’m studying are the earliest forms of symbolic reasoning that a child understands, and when that cognitive ability to reason develops.

Specifically, I’m concerned with a child’s understanding of a scale model, a symbol, that represents a larger space. When the child sees the scale model of a miniature playroom, does the child understand that this little playroom represents a bigger room? And when does a child acquire symbolic understanding? The interesting feature of this research is that we see an abrupt change between ages two-and-a-half and three in a child’s ability to understand scale models. When we experiment with scale models of playrooms, the two-and-a-half-year-old doesn’t understand the relationship between the symbolic room and the actual room, and instead treats it as a separate object. The three-year-old, on the other hand, understands immediately that the model is a symbol for an actual room.

In becoming symbolic creatures, we learn to think abstractly. At age three, children acquire the ability to think about things in two different ways at the same time: as both an object and a symbol for something else. Acquiring symbolic understanding is an important milestone in the cognitive development that helps us figure out how the world operates. Later in life, for example, we use it to read maps and understand languages.

This research helps us appreciate the complexity of human thought in young children. The clearer our knowledge of what children know, the better we can work with them as educators and as parents. Read the rest of this entry »

Written by Joseph Eulo

June 8, 2008 at 1:25 am

Language Development (Video 6)

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Language Development is the sixth program in the DISCOVERING PSYCHOLOGY series. This program outlines the development of language in children. It highlights linguist Noam Chomsky’s theories about the human brain’s predisposition to understand language, and then profiles three scientists working on aspects of psycholinguistics.

One of our main concerns as psycholinguists is figuring out the strategies that children use to discover the grammar of their languages. If you ask ordinary parents how their child learned to talk, they would probably say, “He just imitated. What’s the problem?” Well, one problem is that if you listen to what children say, they often say things they couldn’t have imitated. So a child might say something like “I breaked the glass” or “I falled down.”

Adults don’t say things like “breaked” and “falled,” but children do. These errors are to us the best evidence that the child is doing something creative. The child is in fact working out the structure of the grammar. When you hear a child saying things like “breaked” and “falled,” this means that the child has worked out the pattern for forming the past tense in English. English doesn’t always follow that pattern, but the child has discovered a pattern.

All through the years of language learning, the child is struggling between two opposite problems. On the one hand, he or she wants to adapt language, a particular language, to the natural patterns of thought. On the other hand, the child has to accommodate to the particular grammar of that language. The result, of course, is our adult linguistic capabilities. But along the way, if you look carefully, you can see the interplay between these two factors.

Language is perhaps the most complex cognitive product we have. It’s something that all human beings acquire within the first few years of life, regardless of the circumstances in which they grow up, and to a great extent regardless even of their intelligence. Language reflects something about the basic nature of the human mind. The fact that language is universally so patterned, and that it universally follows such stages of development in its acquisition by children, raises deep questions about the organization of knowledge.

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Written by Joseph Eulo

June 8, 2008 at 1:23 am

Sensation and Perception (Video 7)

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Sensation and Perception is the seventh program in the DISCOVERING PSYCHOLOGY series. This program unravels the complex process of how we see. You’ll learn about visual illusions and what causes them, the biology of perception, the visual pathway, and how the human brain processes information during perception.

Dr. David Hubel explains how cellular structures in the nervous system create the visual pathway between eyesight and brain processing.

In order to understand what we mean by pathway, you need to understand that cells are clustered in the nervous system. They’re aggregated into groups the size of a grain of rice or a marble. One region is connected to another by cables.

So in the case of the visual pathway, you start with the retina where rods and cones are connected by cells. The output is the optic nerve, which contains a million fibers. They end up in one of two regions in the brain, and they connect to other regions, or to the many regions in the cortex. This whole trail is the pathway.

Our studies of single cells tell us that the pathway consists of at least three separate sub-pathways, each with a specific role: one is concerned with color, a second, with form, and a third with movement and depth. If we record any individual cell, depending on the channel, the cell will only respond to one of these three areas.

I want to see how individual cells work when we perceive. We’ve only studied a couple of the visual areas intensely, and there seem to be 18 to 24 different visual areas in the occipital lobe at the back of the brain. Most of our work is on the primary visual cortex, just the first of these areas. It’s exceedingly complex, but we’ll know more about all of the sensory pathways in the brain with more research and experimenting.

Written by Joseph Eulo

June 8, 2008 at 1:22 am