Many people believe
that dogs do dream. Most dog owners have noticed that at various times during
their sleep, some dogs may quiver, make leg twitches or may even growl or snap
at some sleep-created phantom, giving the impression that they are dreaming about something. At the
structural level, the brains of dogs are similar to those of humans. Also,
during sleep the brain wave patterns of dogs are similar
that of people, and go through the same stages of electrical activity observed
in humans, all of which is consistent with the idea that dogs are dreaming.
Actually if dogs
didn't dream this would be a much greater surprise given that recent evidence suggests
that animals that are simpler and less intelligent than dogs
seem to dream. Matthew Wilson and Kenway Louie of the Massachusetts Institute
of Technology have evidence that the brains of sleeping rats are functioning in a
way that irresistibly suggests dreaming. Much of the dreaming that you do at
night is associated with the activities that you engaged in that day. The same
seems to be the case in rats. Thus if a rat ran a complex maze during the day
he might be expected to dream about it at night. While a rat was awake and
learning the maze, electrical recordings were taken from its hippocampus (an
area of the brain associated with memory formation and storage). Researchers
found that some of these electrical patterns were quite specific and
identifiable depending upon what the rat was doing. Later, when the rats were
asleep and their brain waves indicated that they had entered the stage where
humans normally dream, these same patterns of brain waves appeared. In fact the
patterns were so clear and specific that the researchers were able to tell
where in the maze the rat would be if it were awake, and whether it would be
moving or standing still. Wilson cautiously described the results, saying,
"The animal is certainly recalling memories of those events as they
occurred during the awake state, and it is doing so during dream sleep and
that's just what people do when they dream."
Since a dog's brain
is more complex and shows the same electrical sequences, it is reasonable to
assume that dogs are dreaming, as well. There is also evidence that they dream
about common dog activities. This kind of research takes advantage of the fact
that there is a special structure in the brainstem (the pons) that keeps all of
us from acting out our dreams. When scientists removed or inactivated the part
of the brain that suppresses acting out of dreams in dogs, they observed that
they began to move around, despite the fact that electrical recordings of their
brains indicated that the dogs were still fast asleep. The dogs only started to
move when the brain entered that stage of sleep associated with dreaming.
During the course of a dream episode these dogs actually began to execute the
actions that they were performing in their dreams. Thus researchers found that
a dreaming pointer may immediately start searching for game and may even go on
point, a sleeping Springer Spaniel may flush an imaginary bird in his dreams,
while a dreaming Doberman pincher may pick a fight with a dream burglar.
It is really quite
easy to determine when your dog is dreaming without resorting to brain surgery
or electrical recordings. All that you have to do is to watch him from the time
he starts to doze off. As the dog's sleep becomes deeper his breathing will
become more regular. After a period of about 20 minutes for an average-sized
dog his first dream should start. You will recognize the change because his
breathing will become shallow and irregular. There may be odd muscle twitches, and
you can even see the dog's eyes moving behind its closed lids if you look
closely enough. The eyes are moving because the dog is actually looking at the
dream images as if they were real images of the world. These eye movements are
most characteristic of dreaming sleep. When human beings are awakened during
this rapid eye movement or
REM sleep phase, they virtually always report that they were dreaming.
I recently received a
letter from Joseph Baker, which seems to confirm the idea of dogs having dreams
about their everyday activities. I have taken the liberty of reproducing part
of it here.
"I have an anecdote
that you may find interesting, however it requires some back story. About three
years ago I heard a story on the radio about a cognitive scientist
who was trying to understand sleep and dreams. He had a hypothesis describing
how sensory memories replay themselves during early REM sleep. The study he
published had subjects play Tetris [a computer game where you try to line up
falling blocks of various colors] and then report whether or not they saw the
little Tetris bricks in their dreams. This stuck with me because the previous
night I had very vivid dreams involving a hike I had been on earlier. I could
feel the snow and smell the air as though it were real.
"This brings me
to my dog. Goober is a basenji, and like many basenjis he hates water and being
bathed. As soon as my wife finishes bathing him he bolts out of the bathroom
door, finds me, and tries to hide behind me or under me. So one day Goober was
forced to be cleaned and underwent his ritual of hiding behind me. Later that
night he was sleep running. He awoke with a start, and then bolted to my location
to hide under my legs. This was very awkward as I was sitting on the toilet at
the time. I believe that he was dreaming, and I believe that he was dreaming
about having a bath. I believe this because he only engages in this behavior
when a bath is involved."
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