Scientists in the nineteenth century discovered
a lot about life and matter. But exactly what
kind of stuff is the human brain? That one
was—and remains—tricky.
The brain sciences—with experiments and
therapies tied to biological theories of the
body—emerged in the nineteenth century and
came into their own in the early twentieth.
I’m Hank Green and it’s time to look at
some… upsetting stuff.
[INTRO MUSIC PLAYS]
People have always had theories of the mind
and psychological disorder, or “madness.”
Madness was often thought to be a divine punishment,
an act of possession by spirits, or the result
of an imbalance of the humors.
Doctors and priests cared for people dealing
with mental disorders. And as capitalism took
off in Europe, the mentally ill were moved
from villages, where they were looked after
by families, to hospitals in cities—picture
Bedlam—run by a new class of professional
“mad doctors.”
But this wasn’t psychology or psychiatry
as we know it today. In fact, there really
wasn’t a scientific study of the human brain
or the astonishing mental activity it enables.
This only got going around the time of the
Industrial Revolution, with the rise of the
therapeutic asylum, or mental hospital aimed
at helping—and studying—the mentally ill.
Doctor Philippe Pinel of the Bicêtre hospital
in Paris often gets credit for creating the
modern asylum in the late 1700s by ordering
the patients to be unchained.
Credit should actually go to the hospital
superintendent, Jean-Baptiste Pussin—but
Pinel did advocate for moral treatment of
patients rather than physical restraint. And
his generation of asylum doctors marked the
beginning of a shift in thought from madness
to a medical condition of the mind.
But asylums and early psychiatry were only
one part of the story. Nerve doctors treated
anxious private patients. And early neurology
grew from doctors examining the brains of
criminals.
Over the 1800s, proto-neuroscientists shifted
from offering moral explanations for madness
to material explanations tied to brains.
This interest in gray matter came in part
from scientists such as Francis Galton who
looked for explanations about human behavior
in physical bodies, and who sought to make
the life sciences more quantifiable and useful.
Unfortunately, Galton’s version of “useful”
was eugenics, or “improving” the human
species through selective breeding. And scientists
in the 1800s tended to blur the lines between
mental illness, crime, low intelligence, and
a difficult childhood. So moral explanations
for mental illness snuck back into medicine
via “bad brains” instead of religion.
Several researchers looked for connections
between the physical brain and the mind. English
neurologist John Hughlings Jackson, for example,
studied epilepsy and influentially argued
that different bodily functions are tied to
different regions of the brain.
And German doctors Gustav Fritsch and Eduard
Hitzig electrically stimulated parts of the
exposed brains of dogs, making their paws
twitch. This showed experimentally that specific
parts of the brain coordinate motor functions.
And then we've got a name you've heard!
Russian physiologist Ivan Pavlov focused on
conditioned reflexes: he taught dogs to associate
the sound of a metronome with being fed, causing
them to salivate when presented with the sound
alone.
Pavlov’s stimulus–response work became
foundational to the school of psychology called
behaviorism. With this approach, psychologists
focused on environmental stimuli that affect
how someone behaves rather than what they’re
thinking and feeling.
Meanwhile, Spanish neuroscientist Santiago
Ramón y Cajal developed a method of staining
brain tissue and discovered that it is made
up of—wait for it—individual cells! Just
like the rest of the body.
After much painstaking lab work, he convinced
the rest of the scientific community of this
idea, called the “neuron doctrine” after
the name of the brain cell.
Around this time, other researchers set up
scientific laboratories to study the workings
of the human mind. BTW, we’re mostly focusing
on the mind today, but we’ll talk more about
the brain after World War II.
German doctor Wilhelm Wundt founded the first
psychology lab, at the University of Leipzig,
in 1879, establishing psychology as a discipline
separate from other sciences.
Wundt’s student, British psychologist Edward
Bradford Titchener, developed a structuralist
psychological theory based on Wundt’s ideas
starting in 1892. Structuralism is a philosophy
that tries to understand things by seeing
how their parts fit together, regardless of
what they do. Titchener tried to define the
“unit elements” of consciousness, hoping
to work out a periodic table for the mind.
Meanwhile—heavily influenced by Charles
Darwin—American philosopher William James
developed functionalism theory, writing the
Principles of Psychology in 1890. Functionalism
is a philosophy that tries to understand things
by working out the purpose for them.
Finally, American psychologist G. Stanley
Hall, who studied under both Wundt and James,
set up the experimental psychology lab at
Johns Hopkins and went on to professionalize
the whole field. He started the American Journal
of Psychology in 1887 and founded the American
Psychological Association in 1892.
Thus, by the early 1900s, both the scientists
studying brains and nerves, and those studying
consciousness and human behavior had set up
professional labs to explore shared research
questions.
But the sciences of the brain and mind became
more well known due to the application of
psychological theories outside of the lab.
Y’all know who I’m talking about, right?
Austrian physician-turned-talk therapist-turned-controversial
philosopher Sigmund Freud became so famous
that historians sometimes call the twentieth
century “the Freudian century.”
To introduce him, let’s head back to 1862,
when Europe’s most famous brain doctor,
Jean‑Martin Charcot, worked at Paris’s
Salpêtrière hospital, then the largest in
the world.
Charcot saw patients but was also a big-time
brain collector. And he realized that maybe
there were other, new ideas worth trying.
His blend of brain research-plus-therapy,
the clinico-anatomical method, was the basis
for Freud’s work.
Charcot focused on trying to understand the
“laws” governing hysteria—which has
a long, problematic history and isn’t a
disease today.
But back in the nineteenth century, it was
a way of describing various problems, including
loss of motor control, paralysis, unexplained
fears, fainting, emotional outbursts, and
a host of other ailments. It was a diagnostic
trash can. Plus, a way to describe
women with independent ideas!
Charcot tried out a lot of methods: he was
one of the first users of the camera in medicine,
moving toward mechanical objectivity, or trusting
instruments over human senses.
A lot of his photos of hysteric patients were
lurid and super weird by today’s standards.
But the point of the history of science isn’t
to prove how awesome and ethical we are today,
but to understand how people in the past made
sense of their worlds.
Charcot also explored mesmerism, or hypnosis.
He showed that hypnosis can cause physical
symptoms, which he took to prove that hysteria
was a neurological, not a psychological illness.
That is, he thought people with mental illnesses
were more likely to be affected by hypnosis
because they had bad physical brains.
In 1885, the young Freud attended Charcot’s
lectures on hysteria and became obsessed with
mental illness.
Now, it’s important to understand the halfway
position that Freud occupied in medicine.
He couldn’t take an M.D. in Germany because
he was too… Jewish. Instead, he became a
“nerve doctor,” treating neurasthenia,
or bad or exhausted nerves—which was the
rich-person term for hysteria.
But he was open to new ideas. Freud learned
a lot from Charcot. But then he found out
that Josef Breuer, a senior nerve doctor in
Vienna, was using hypnosis to encourage patients
to talk rather than move.
Freud started working with talk therapy and
realized that many hysterical patients were
smart and otherwise “normal.” And those
suffering from hysterical “paralysis”
were paralyzed in ways that didn’t make
anatomical sense. He decided that hysterical
paralysis was not an anatomical problem.
In 1893, Breuer and Freud published Studies
on Hysteria, theorizing that mental disorders
are not the result of bad biology but bad
memories, such as sexual abuse. They suggested
that the best therapy was helping them recover
those memories, which were often suppressed.
Breuer and Freud fell out, but from their
work together, Freud developed a new form
of therapy, psychoanalysis, that caught on
worldwide.
Help us out, ThoughtBubble:
Psychoanalysis was based on talking about
early childhood experiences, relationships
with parents, early sexual encounters, and
dreams. The couch became a therapeutic tool.
And dreams became important for therapists
after Freud’s influential 1900 book, Interpretation
of Dreams.
Through his work listening to patients and
trying to decode their anxieties, Freud also
opened up the study of sexuality—or, to
coin another big question: where do funny
feelings come from? For Freud the answer was
a form of psychic energy called libido that
floated around the brain and had to go somewhere.
Eventually, Freud’s work led him to develop
a three-part framework for how the human mind
functions and what it even is:
At the bottom, there is a fairly animalistic
layer called the id or unconscious drives,
deep-seated fears and desires.
Above that sits the ego, or the waking, conscious
mental interface with reality. Hey, it me!
And finally, metaphorically on top of the
ego sits the superego, the mind’s internalized
censor and the voice of society, religion,
and moral norms.
For Freud, our minds are the outcome of a
conflict between these basic desires, rational
desires, and social desires. This “iceberg
theory” of consciousness—that we only
understand a small part of our own minds—has
had an enormous influence on popular culture.
Thanks ThoughtBubble. Freud emphasized that
this was not an anatomical model, but a medical
one, intended to help therapists access their
patients’ unconsciousness, and a sociocultural
one that accounted for… all of history and
religion.
To Freud, civilization represses sexual and
aggressive drives, so it’s a necessary evil.
But… was this sort of theorizing even still
science?
Regardless, psychoanalysis blew up. And Freud
treated it as a foregone success: in 1914,
he published—maybe a little prematurely—On
the History of the Psychoanalytic Movement.
Something else happened in 1914: the Great
War, or World War I, broke out. Over the next
four years, thousands of soldiers returned
from the front complaining of sensory and
motor disorders and loss of memories, but
with no obvious physical causes.
This became “shell shock,” later rethought
of as post-traumatic stress disorder. Talk
therapists played a role in treating soldiers,
and psychiatrists found a steady source of
patients.
Freud also continued to collaborate with other
psychologists. His Swiss colleague Carl Jung
invented the word association test and the
theory of the collective unconscious, or a
deep part of the mind supposedly derived from
ancestral memory and myth, not individual
experience.
And Freudian ideas entered mainstream psychiatry
through Swiss psychiatrist Eugen Bleuler,
who coined the term “schizophrenia.”
The mind sciences found perhaps an even more
fertile home in industry. Advertisers including
Freud’s nephew, Edward Bernays, adopted
theories of mind and behavior in order to
sell consumers increasingly mass-produced
goods. And J. B. Watson—the founder of behaviorism—became
an advertising executive.
In a way, Freud helped sell Fords. And other
industries looked to theories of mind in order
to make their organizations run more smoothly.
Next time—let’s get radioactive with a
legit family of geniuses: it’s time to meet
Marie Curie.
Crash Course History of Science is filmed
in the Dr. Cheryl C. Kinney Studio in Missoula,
MT and It’s made with the help of all of
these nice people. Our animation team is Thought Cafe.
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