When people dream, their breathing becomes shallow, their heart beats faster, their blood pressure rises, their cerebral blood volume doubles, and their faces and limbs twitch. At this time, the eyeball can be measured by eye movement instrument, and fast waves must appear on EEG at the same time. Therefore, generally speaking, "rapid eye movement period" plus "EEG fast wave" can be used as a sign of dreaming. Some animals have been measured by the above method. When the frog sleeps, there are only a few slow wave curves, and there are no "EEG fast wave" and "REM" periods, which can confirm that the frog will not dream. Turtles have "rapid eye movement period" and "EEG fast wave" during sleep, but the time is very short, accounting for only 2% of the sleep time. It can be confirmed that turtles have very little time to dream. Cats, dogs and monkeys all dream, and the dream time is longer, among which monkeys are the longest, dogs are the second, and cats are the shortest. It is an interesting question to study animal dreaming.
Animals dream. What did they dream? People are eager to find out this problem. However, animals can't talk and can't tell us, which is really a problem. American scientists did an experiment on monkeys: set a screen in front of a monkey, and the same picture appeared repeatedly on the screen; Every time this photo appears on the screen, the monkey is forced to push a lever around it. If the monkey refuses to carry it out, hit it with an electric baton. After a few days, the monkey formed a conditioned reflex: as soon as he saw the picture, he took the initiative to push the lever. Later, scientists found that monkeys push the lever from time to time during sleep. This shows that the monkey "saw" the picture in his sleep. French physiologist poitiers. Noff made a very interesting experiment with cats. He chemically and surgically blocked the part of the cat's brain called pons. Therefore, the cat will act according to its dreams. After the operation, the sleeping cat suddenly looked up, looked around, and then got up and circled as if looking for food. Suddenly it raised its front paws, put its ears close to its head and pounced on the imaginary enemy. Noff also observed two cats that had been operated on together, and found that the two cats that had been living in harmony suddenly fought when they were asleep. In order to prove that these behaviors were made in his sleep, Noff deliberately knocked on the object next to the cat to make a sound, and even put the mouse next to it. But the two cats were indifferent to all the events around them, and they continued to attack their opponents. Noff believes that the two cats are facing their dream rivals. Cats can dream, but each dream lasts no more than 5 minutes.