The Power of Motivation: Crash Course Psychology #17
You’ve probably heard this story.
Aron Ralston was out climbing in Utah’s Bluejohn
Canyon when a giant rock shifted under his
feet, and he fell, pinning his right arm to
the canyon wall. He was stuck, and worse,
he hadn’t told anyone where we was going.
For the next five days, Ralston tried to move
and chip away at the rock. He ate his remaining
food, drank the last of his water. Eventually
he drank his own urine, and started videotaping
But then something happened. Ralston had a
dream. He saw himself as a father, picking
up his son, and with that vision, an overpowering
will to survive kicked in. He broke his arm
bones, sawed through his flesh with a dull
pocket knife, and freed himself.
Ralston harnessed some of our most powerful
psychological forces — hunger, thirst, desire
to be part of a family, need to return to
the human community — they ignited his tenacity,
which allowed him to do an incredible thing.
He harnessed the power of motivation.
Obviously, in a big, big way.
In its most basic sense, motivation is the
need or desire to do something. Whether that
need is biological, social, or emotional,
and whether that something is making dinner,
going to college, or cutting off your arm,
motivation is what gets you moving.
But the big question is, why? Why do we do
anything? I mean, why ever bother changing
out of my sweatpants?
Psychologists often view motivation in one
of four ways. On their own, none of these
theories is perfect, but taken together, they
help us understand what drives us. Let’s start
with the first theory: an evolutionary perspective.
For a while in the early 20th century, it
was popular to think of all behaviors as instincts,
or innate drives to act a certain way. But
this so-called Instinct Theory was misguided,
in part because the presence of a tendency
doesn’t always mean it’s supposed to be there.
Like, we can imagine why a bunch of people
might start rioting at a heated soccer match,
but to say that they’re supposed to — a little
Evolution is a far more complex, chaotic,
and interesting process than that. Plenty
of behaviors could just be accidents of evolution
— late paleontologist Stephen Jay Gould called
these accidents “spandrels,” or traits that
rather than being “adaptive” just stuck around
as byproducts of other processes.
Today we define instincts as complex, unlearned
behaviors that have a fixed pattern throughout
a species. For example, dogs instinctively
shake their fur when wet, salmon return to
the stream in which they hatched, and human
babies know how to suckle just minutes after
These are true, genetically-predisposed instincts
that do not require learning.
But today we understand that while certain
tendencies may be genetic, individual experience
plays a major role in behavior and motivation,
So another theory of motivation suggests that
a physiological need, or drive, simply compels
us to reduce that need. This is called the
drive-reduction theory. This can be as simple
as hearing my stomach growl, and looking for
a burrito. My need is food, my drive is hunger,
my drive-reduction behavior is burrito.
Drive reduction is all about maintaining your
body’s homeostasis — the physiological balance
of its systems.
As much as we’re pushed to reduce our drives,
we’re also pulled along by incentives — the
positive or negative stimuli that either entice
or repel us. The mouth-watering smell of that
burrito pulls me toward it, just as much as
my hunger pushes me there.
However, we’re also clearly more complicated
than our homeostatic systems, and drive-reduction
theory may over-simplify a lot of our behavior.
For example, a person may fast for days, ignoring
their body’s hunger to honor some spiritual
or political cause; and I know I’m not the
only one who sometimes eats when I’m not actually
So a third theory — the theory of optimal
arousal — attempts to fill in some of those
gaps. It suggests rather than just reducing
a drive or tension, like hunger, we’re motivated
to maintain a balance between stimulation
Say you’re holed up in your house all weekend
studying. You’re bored and lonely and gettin’
weird, so you call up some friends to go mountain
biking or to a karaoke bar or whatever you
like to do to for stimulation.
The idea here is that you want to hit the
right level of arousal — which, take note,
psychologists often use in a non-sexual sense
— without getting overstimulated and stressed.
So if you nearly break your face on that bike
ride, or if the Journey covers at karaoke
start getting too intense, you may need to
back off and take a nap.
Of course everyone has a different level of
optimal arousal, and I’m guessing Aron Ralston’s
was fairly high. Adrenaline junkies may jump
out of planes to hit their ideal level, whereas
others might be satiated by an engaging book,
or new knitting pattern. No matter which,
the optimal arousal theory suggests that we’re
motivated to avoid both boredom and stress.
And obviously not all needs are created equally.
If I’m suffocating and can’t catch a breath,
I’m not going to be thinking about eating
that burrito. And if I’m about to be ravaged
by lions, I’m not going to worrying about
American psychologist Abraham Maslow illustrated
this shuffling of priorities in the mid-1900’s
with his famous hierarchy of needs.
Down at the bottom of the pyramid you’ll find
our most basic physiological needs for food,
water, air, and moderate temperatures.
The next rung up speaks to our need for safety,
then comes love and belonging, followed by
esteem or respect, and finally, once all those
needs have been met, we have the relative
luxury of being motivated by self-actualization
and spiritual growth, and yoga retreats and
Of course there are problems with Maslow’s
vision. Empirical research hasn’t really supported
his hierarchy. We tend to skip around on that
pyramid all the time, and the importance of
those higher-level needs may vary depending
on our culture and finances and personalities.
But still, everyone is restricted by the lowest
levels of the pyramid. So, regardless of the
theories about why we have them, most schools
of psychological thought agree that we are
driven by at least three big motivators: sex,
hunger, and the need to belong.
We’ll do a whole lesson later about all sorts
of sex-related stuff, including how it motivates
us. There’s a lot there. For now, let’s just
say that sexual motivation is how we promote
the survival of our species through recreation
and/or procreation – both of which help human
communities bond and expand. Without it, none
of us would be here today, thinking about
burritos and severed arms and sex and stuff.
Internally, we are biologically driven to
knock boots by our sex hormones. We’re also
motivated by psychological and sociocultural
influences – ranging from suggestive external
stimuli plastered all over billboards, magazines,
and TVs in the form of, you know, scantily-clad
bodies sprawled out on beaches to more genteel
desires like love, family, or adherence to
personal, religious, or cultural values.
Sex is a big motivator, but it isn’t precisely
a need, no matter what anyone has told you.
People do not die without it.
After air and water, food is our body’s greatest
need, and thus obtaining food is one of our
Hunger may seem pretty simple. Eat food, stay
alive. But physiologically and psychologically,
there is a lot going on. And like so many
things, it starts in the brain.
The sensation of hunger usually begins with
a drop in your blood-sugar level. Glucose
is our body’s primary source of energy, and
while you might not initially feel it drop,
your brain will.
Your hypothalamus monitors your blood chemistry,
and responds to both high levels of the “hunger
hormone” ghrelin, and low levels of glucose
by triggering that feeling of hunger reminding
you to eat something. I am in fact experiencing
it right now!
Once you’ve eaten that burrito, your metabolism
takes over, converting that food into energy.
But while our physiological need for calories
varies depending on our body size and composition,
your gender, and your age, our hunger is also
shaped by our psychology, culture, and mood.
And these factors don’t just rule when we’re
hungry, they also guide what we’re hungry
Biologically speaking, most humans, and many
other animals, have a genetic taste for sweets
and fatty foods, because they’re typically
high in energy. But other taste preferences
are conditioned through experience and culture.
I may have an aversion to oysters because
they once made me sick, and love gingerbread
cookies because my grandma used to make them.
Although popular in Cambodia, I’m not too
keen on eating fried tarantulas, just as lots
of folks around the world think that the very
idea of peanut butter is gross.
Still, the feeling of hunger affects us the
During World War Two in the US, some conscientious
objectors volunteered for medical research
as an alternative way to serve their country.
Perhaps the most famous of these studies was
physiologist Ancel Keys’ Minnesota Hunger
Experiment, which measured the effects of
semistarvation, by partially starving its
While ethically dubious, the experiment was
geared toward understanding the many small
and large effects of hunger, which was plaguing
Europe at the time.
The study started in 1944, by feeding 36 young,
healthy men a normal diet for three months,
then halving their caloric intake for six
months, then slowly rehabilitating them to
normal weight during the last three months.
They ate mostly wartime-foods like root vegetables,
bread, and pastas, and were required to walk
22 miles, and participate in various work
and educational activities, for 40 hours each
week. The goal was to see a 25 percent drop
in body weight during the starvation period.
As you can imagine, the changes were dramatic.
The men became gaunt and listless, and showed
a decrease in strength, heart rate, and body
But the psychological effects were perhaps
even more dramatic. The men became totally
obsessed with food. They dreamed about it,
talked about it all the time, read cookbooks.
They lost interest in sex and jokes and social
activities. They were irritable, anxious,
In the end, they were all rehabilitated, but
the study gave us some understanding of the
devastating psychological effects of starvation.
It also showed us something of the social
effects, as the men withdrew from one another
and isolated themselves. As one fundamental
need was frustrated, these men experienced
the decline of another – the need to belong.
Humans are social animals. Evolutionarily
speaking, it’s fair to say that social bonding
has helped us survive. It’s a tough world
out there, and we’ve got a lot better shot
at thriving if we’re sharing resources and
responsibilities, protecting and supporting
each other in groups.
That isn’t say you need to be joined at the
hip with everyone–our social needs have to
be balanced with our autonomy, or sense of
personal control, so we feel both connected
But sometimes we’re denied that sense of belonging.
We’ve all experienced the pain of being ignored
or rejected at some point in our lives. It’s
worse than just about anything.
The evidence for this is abundant – one recent
study suggested that teenagers who had a sense
of belonging to their community had better
health and emotional outcomes than those who
didn’t feel like they belonged.
Cultures all over the world actually use ostracism,
or social exclusion, as a type of punishment.
Whether it’s kids in time-out, adults in exile,
or prisoners in solitary confinement, separation
feels like a punch in the gut.
Never underestimate the power behind what
motivates us. The need to survive, the need
to belong… if you can harness that motivation,
you can do just about anything. Just ask Aron
If you were motivated to learn today, hopefully
you took in four theories of motivation including
the evolutionary perspective, drive-reduction,
optimal arousal, and Maslow’s hierarchy of
needs, and how sex, hunger, and the need to
belong motivate us.
Thanks for watching, especially to our Subbable
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This episode was written by Kathleen Yale,
edited by Blake de Pastino, and our consultant
is Dr. Ranjit Bhagwat. Our director and editor
is Nicholas Jenkins, the script supervisor
is Michael Aranda, who’s also our sound designer,
and the graphics team is Thought Café.