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This is Luna.
You guys know Luna.
She's my adorable labradoodle.
I might be a little bit biased, but I
think that dogs are pretty clever,
and research has shown that dogs miss us when we're gone,
they can understand our language,
and they can have optimistic or pessimistic personalities.
On average, dogs sleep for 14 hours a day,
and when I see Luna sleeping, I often wonder, do dogs dream?
You know, like, humans do.
I've mentioned before that when humans sleep,
we cycle through stages of light and deep sleep.
The first and second stages are light sleep,
and we can be woken up easily.
When you reach the third stage, you enter deep sleep,
and following that is rapid eye movement,
REM sleep, where your eyes actually move back and forth
and you're most likely to dream.
Researchers have found that animals
go through the same series of sleep cycles as we do,
and some researchers dug a little deeper.
One study at MIT trained rats to run around a circular track
for a food reward.
Researchers monitored their brain during that task
and again when they were sleeping.
When the rats entered REM sleep, you know,
when most dreaming occurs, researchers
observed that half of their REM episode
showed the same unique brain activity as when they were
running along the track, awake.
Their memories were even replayed
at about the same speed.
In fact, their brain activity, asleep and awake,
was so similar, the researchers said
they could reconstruct where the rat was on the track
and whether it was running or walking.
It's generally thought that sleep
allows us to consolidate and encode memories
to learn things.
So the rats were learning about that circular track,
and a later study, also an MIT, found
that the visual areas of rats' brains
are active in dreaming as well as their memory areas,
suggesting that animals dream in pictures, too.
In fact, most land mammals experience REM sleep,
whether it's those mice dreaming of cheese or us
dreaming about pizza.
You've probably seen a dog in REM sleep before.
In dogs, rapid eye movement sleep
is like rapid everything movement.
They twitch their little noises, they move their mouths,
and they often look like they're running or digging.
So I wonder, what would dogs dream about?
Trace here for D News.
A new study has found that squirrels
are meant to be chased.
It's their only purpose in the ecosystem.
Science says that the secret to good health
is 10 Milk-Bones a day; that's 9 more than previously thought.
Researchers from the University of "Barkansas"
suggest that you're a really good dog, Luna.
Yep, I'm talking to you.
Even though we can't ask dogs, based on human brain activity
and what we've observed in animals,
we're pretty sure that dogs do dream,
and their doggie dreams are based
on their daily activities.
Whether it be chasing chipmunks, their food, or maybe
they even dream about their owners.
And the smaller a dog is, the more it will dream.
A toy poodle may dream once every 10 minutes.
An Irish wolfhound once every hour or two.
In his work, The History of Animals,
Aristotle wrote, it would appear that
not only do men dream, but horses also, and dogs,
and oxen; aye, and sheep, and goats.
And dogs show their dreaming by barking in their sleep.
And Aristotle was pretty close to the truth.
We know now that dogs can have nightmares,
they can sleephunt, sleepwalk, and even sleep pounce.
So while we can say that dogs do dream,
we can't say whether they know their dreams are dreams,
or if they remember them in the morning.
What do you think, Luna?
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And if you want more doggie science, follow me over
to D News where I ask, can dogs be pessimists?
And subscribe to Braincraft out for more brainy videos
every week.
Can they self "re-pawt"?
Is the water in their bowl half empty, half full?
Well, researchers at the University of Sydney
looked into this in a 2014 study using 40 dogs
that were all different breeds.
What do you think, Luna?
Luna don't care.