Our World Tuesday
Like humans, dogs have two main types of sleep: rapid eye movement (REM) sleep and
In SWS, brain waves are slow, undulating and of high amplitude much like those in a
When REM sleep is achieved they are at their most relaxed and are most difficult to waken. It is during this more profound physical sleep that their eyes begin to dart and the brain waves pick up pace. Humans awakened from this state report that they have been dreaming; dogs are probably dreaming too when they are in REM sleep, although no dog has ever told anyone about a dream he's had.
Incidentally, adult dogs spend about 10 to 12 percent of their sleeping time in REM sleep. Puppies spend a much greater proportion of their sleep time in REM sleep, no doubt compacting huge quantities of newly acquired data.
And if you've ever wondered whether dogs that seem to be running during sleep are dreaming of catching rabbits or something similar, you can safely say they are.