Name: 心と脳。科学のクラッシュコースの歴史 #30 (The Mind/Brain: Crash Course History of Science #30)
Uploaded: 2021-01-14T10:27:49.000Z
Duration: 12 min 47 s
Description: VoiceTubeの動画で発音を聞きながら英語表現を覚えよう！学べる英語：

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.

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

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

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

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

Over the 1800s, proto-neuroscientists shifted from offering moral explanations for madness

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.

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

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

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

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

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

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

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

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

In 1885, the young Freud attended Charcot's lectures on hysteria and became obsessed with