Name: 心理学研究 - クラッシュコース心理学 #2 (Psychological Research - Crash Course Psychology #2)
Uploaded: 2021-01-14T05:37:52.000Z
Duration: 10 min 51 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：

Can week-old pizza cause psychedelic hallucinations? Does coffee make you smarter? Or does it just

Like a bunch of psychology itself, questions like this can seem pretty intuitive. I mean,

people may not be the easiest organisms to understand, but you're a person, right? So

you must be qualified to draw, like, some conclusions about other people and what makes

But it's important to realize that your intuition isn't always right. In fact, sometimes it

is exactly wrong, and we tend to grossly underestimate the dangers of false intuition. If you have

an idea about a person and their behavior that turns out to be right, that reinforces

your trust in your intuition. Like if one of my buddies, Bob, begins eating that deep-dish

pizza that's been in the fridge for the past week but he eats it anyway and soon starts

to wig out, I'll say "Dude, I told you so". But if I'm wrong and he's totally fine, I

probably won't even think about it ever again.

This is known as 'Hindsight Bias" or the "I-Knew-It-All-Along" phenomenon. This doesn't mean the common sense

is wrong, it just means that our intuitive sense more easily describes what just happened,

than what will happen in the future. Another reason you can't blindly trust your intuition

is your natural tendency toward overconfidence. Sometimes, you just really, really feel like

you're right about people when actually you're really, really wrong. We've all been there.

We also tend to perceive order in random events, which can lead to false assumptions. For example,

if you flip a coin five times you have equal chances of getting all tails as you do getting

alternating heads and tails. But we see the series of five tails as something unusual,

as a streak, and thus giving that result some kind of meaning that it very definitely does

That is why we have the methods and safe-guards of psychological research and experimentation,

and the glorious process of scientific inquiry. They help us to get around these problems

and basically save the study of our minds from the stupidity of our minds. So I hope

that it won't be a spoiler if I tell you now that pizza won't make you trip, and coffee

In most ways psychological research is no different than any other scientific discipline,

like step one is always figuring out how to ask general questions about your subject and

turn them into measurable, testable propositions. This is called operationalizing your questions.

So you know how the scientific method works -- it starts with a question and a theory,

and I don't mean theory in the sense of like, a hunch that say, a quad-shot of espresso

makes you think better. Instead, in science a theory is what explains and organizes lots

of different observations and predicts outcomes. And when you come up with a testable prediction,

Once your theory and hypothesis are in place, you need a clear and common language to report

them with, so for example, defining exactly what you mean by "thinking better" with your

espresso hypothesis will allow other researchers to replicate the experiment. And replication

is key. You can watch a person exhibit a certain behavior once, and it won't prove very much,

but if you keep getting consistent results, even as you change subjects or situations,

This is a problem with one popular type of psychological research: case studies, which

take an in-depth look at one individual. Case studies can sometimes be misleading, because

by their nature, they can't be replicated, so they run the risk of over-generalizing.

Still, they're good at showing us what CAN happen, and end up framing questions for more

extensive and generalizable studies. They're also often memorable and a great story telling

device psychologists use to observe and describe behavior. Like, say the smell of coffee makes

Carl suddenly anxious and irritable -- that obviously doesn't mean that it has that same

effect on everyone. In fact, Carl has terrible memories associated with that smell, and so

his case is actually quite rare. Poor Carl. But you would still have to look at lots of

other cases to determine that conclusively.

Another popular method of psychological research is naturalistic observation, where researchers

simply watch behavior in a natural environment, whether that's chimps poking ant-hills in

the jungle, kids clowning in a classroom or drunk dudes yelling at soccer games. The idea

is to let the subjects just do their thing without trying to manipulate or control the

situation. So yeah, basically just spying on people. Like case studies, naturalistic

observations are great at describing behavior, but they're very limited in explaining it.

Psychologists can also collect behavioral data using surveys or interviews, asking people

to report their opinions and behaviors. Sexuality researcher Alfred Kinsey famously used this

technique when he surveyed thousands of men and women on their sexual history and published

his findings in a pair of revolutionary texts, Sexual Behavior in the Human Male and Female

Surveys are a great way to access consciously held attitudes and beliefs, but how to ask

the questions can be tricky; subtle word choices can influence results. For example more forceful

words like "ban" or "censor" may elicit different reactions than "limit" or "not allow". Asking

"Do you believe in space aliens?" is a much different question than "Do you think that

there is intelligent life somewhere else in the universe?" It's the same question, but

in the first the subject might assume you mean aliens visiting earth, and making crop

circles and abducting people and poking them.

And if how you phrase surveys is important, so is who you ask. I could ask a room full

of students at a pacifist club meeting what they think about arms control, but the result

wouldn't be a representative measure of where students stand, because there's a pretty clear

sampling bias at work here. To fairly represent a population, I'd need to get a random sample

where all members of the target group, in this case students, had an equal chance of

So once you've described behavior with surveys, case studies, or naturalistic observation,

you can start making sense out of it, and even predict future behavior. One way to do

that is to look at one trait or behavior is related to another, or how they correlate.

So let's get back to my buddy Bob who seems to think that his refrigerator is actually

some kind of time machine that can preserve food indefinitely. Let's say that Bob has

just tucked into a lunch of questionable leftovers, pizza that may very well have had a little

bit of fungus on it. But he was hungry, and lazy, and so he doused it in Sriracha. Suddenly,

he starts seeing things: green armadillos with laser beam eyes.

From here we could deduce that eating unknown fungus predicts hallucination, that's a correlation.

But correlation is not causation. Yes, it makes sense that eating questionable fungus

would cause hallucinations, but it's possible that Bob was already on the verge of a psychotic

episode, and those fuzzy leftovers were actually benign. Or there could be an entirely different

factor involved, like maybe he hadn't slept in 72 hours, or had an intense migraine coming

on, and one of those factors caused his hallucinations. It's tempting to draw conclusions from correlations,

but it's super-important to remember that correlations predict the possibility of cause-and-effect

So we've talked about how to describe behavior without manipulating it and how to make connections

and predictions from those findings. But that can only take you so far; to really get to

the bottom of cause-and-effect behaviors, you're gonna have to start experimenting.

Experiments allow investigators to isolate different effects by manipulating an independent

variable, and keeping all other variables constant, or as constant as you can. This

means that they need at least two groups: the experimental group, which is gonna get

messed with, and the control group, which is not gonna get messed with.