What dreams they see animals
“It is noticed that almost all animals, whether aquatic, aerial or terrestrial, it is evident fall into a dream state,” wrote Aristotle in his treatise “On sleep and wakefulness”. But go to our “lesser brothers” in their dreams?
Jason Goldman, a graduate student at the University of southern California (Los Angeles), evolutionary psychology examines human and animal. The young scientist said that today there are two main ways to look into the minds of sleeping cats, birds and other living creatures. The first method is to observe the physical behavior of animals during the different phases of the cycle “sleep-Wake”. The second is whether their brain in the sleep state similarly to how this state operates our brain.
Since school biology lessons, we know that during sleep the brain passes through several periods with different activity levels. One of them, with relatively lower activity, called slow wave sleep. The second, during which brain activity is almost the same as during wakefulness, was named the fast phase, or REM-phase (from the English. REM – rapid eye movement, rapid eye movement). At this time, the spinal cord sends a powerful braking impulses, paralyzing all our body and making it impossible to move, speak or scream.
However, in accordance with the International classification of sleep disorders (mCRs), “during sleep, people can strike blows with fists, kicking, jump out of bed and even run. Such manifestations generally are consistent with described upon waking dreams”. For such people (and those who sleep next to them) injuries are not uncommon, much of the mass of the hazards of “lunatics”, and can not speak.
The same Greek philosopher, mentioned by us earlier, in his “History of animals” argued that because dogs sometimes bark in my sleep, it means that they have dreams. Seriously interested in this issue in the 60-ies of the: blocking the neurons that sends the spinal cord in order to paralyze all the muscles, scientists could freely observe the actions of the cats and dogs in the process of dreams. It turned out that the animals have actions, usually committed by them in the waking state. They are looking for imaginary prey and attacking her, defending their territory and running away from invisible enemies, etc.
However, observation of the movements of sleeping is not the only way to look into their dreams. Today, researchers more opportunity to study electrical and chemical processes that occur in brain cells of animals, without any harm to them. Scientists from the Massachusetts Institute of technology, Kenuey Louis and Matthew Wilson recorded the activity of hippocampal neurons of rats. This part of the brain is involved in the mechanisms of formation of emotions and memory consolidation. Comparing the activity of the same neurons during wakefulness, when the rats ran on the maze and during sleep, the researchers found virtually no differences. In other words, during sleep rats mentally ran through the familiar maze of his own design – and even was not difficult to determine the exact location of the sleeping rodent in its nooks and crannies.
Biologists from the University of Chicago, Amish Dave and Daniel Margoliash, discovered something similar when studying the Zebra Finch brain. These birds are born without genetic models of singing: their melodies they have to learn. When the birds were awake, the special robutus archistriatalis neurons in their forebrain came in arousal in response to individual songs. Scientists can determine which cells are responsible for a particular note, and was able to reconstruct the whole song from beginning to end. Then they examined the electrical activity of the brain of sleeping Finch and came to the conclusion that during sleep the bird’s loud, note for note, practicing for their “Aria”!
But realize whether rats that mentally run through their mazes, while in the dream state? Guess if the birds that in the dream master the technique of singing? To these questions yet hard to answer – because even people very rarely understand in the dream that sleep, no matter how absurd and implausible the plot is revealed only after waking up. Although I must admit that we are the only ones who after some training are able to realize themselves in their own dreams and start to manage it at their discretion.