![]() ![]() In dreams the mind tries to make sense of its own activity, resulting in dreams. In the waking world we must make sense of external events. ![]() In dreams, the planning and foresight areas of the brain are suppressed, allowing the mind to react creatively to wherever it wanders - much like a jazz improviser responds to fellow musicians to inspire what they play.Īs hypnic jerks escape during the struggle between wake and sleep, the mind is undergoing its own transition. When this does happen, it illustrates our mind's amazing capacity to generate plausible stories. This is an example of the rare phenomenon known as dream incorporation, where something external, such as an alarm clock, is built into your dreams. Some people report that hypnic jerks happen as they dream they are falling or tripping up. In other words, hypnic jerks are the last gasps of normal daytime motor control. As sleep paralysis sets in remaining daytime energy kindles and bursts out in seemingly random movements. Few battles are won completely in a single moment. What happens next is not fully clear, but it seems that part of the story is that the struggle for control of the motor system is not quite over yet. The VLPO drives sleepiness, and its location near the optic nerve is presumably so that it can collect information about the beginning and end of daylight hours, and so influence our sleep cycles.Īs the mind gives in to its normal task of interpreting the external world, and starts to generate its own entertainment, the struggle between the reticular activating system and VLPO tilts in favour of the latter. Opposing this system is the ventrolateral preoptic nucleus: 'ventrolateral' means it is on the underside and towards the edge in the brain, 'preoptic' means it is just before the point where the nerves from the eyes cross. When the reticular activating system is in full force we feel alert and restless - that is, we are awake. This is nestled among the parts of the brain that govern basic physiological processes, such as breathing. ON at night, OFF during the day), we have two opposing systems balanced against each other that go through a daily dance, where each has to wrest control from the other.ĭeep in the brain, below the cortex (the most evolved part of the human brain) lies one of them: a network of nerve cells called the reticular activating system. Rather than having a single “sleep-wake” switch in the brain for controlling our sleep (i.e. Instead, hypnic jerks seem to be a sign that the motor system can still exert some control over the body as sleep paralysis begins to take over. They are most common in children, when our dreams are most simple and they do not reflect what is happening in the dream world - if you dream of riding a bike you do not move your legs in circles. ![]() Seeing a sleeping persons' eyes move is the strongest sign that they are dreaming. These movements generated in the dream world escape from normal sleep paralysis and leak into the real world. ![]() If, for example, we dream we are watching a game of tennis our eyes will move from left to right with each volley. When we dream, our eyes move according to what we are dreaming about. The most common movements we make while asleep are rapid eye-movements. Two kinds of movements escape the dreaming brain, and they each have a different story to tell. Events in the outside world usually get ignored: not that I’d recommend doing this but experiments have shown that even if you sleep with your eyes taped open and someone flashes a light at you it is unlikely that it will affect your dreams.īut the door between the dreamer and the outside world is not completely closed. Even during the most vivid dreams our muscles stay relaxed and still, showing little sign of our internal excitement. Normally we are paralysed while we sleep. Nobody knows for sure what causes them, but to me they represent the side effects of a hidden battle for control in the brain that happens each night on the cusp between wakefulness and dreams. Me, I am fascinated by these twitches, known as hypnic jerks. Some people are startled by them, others are embarrassed. As we give up our bodies to sleep, sudden twitches escape our brains, causing our arms and legs to jerk. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |