There are four stages of Non-REM sleep. During Stage 1, the eyes are closed. One can be awakened without difficulty; however, if aroused from this stage of sleep, a person may feel as if he or she has not slept. The heart rate slows and the body temperature decreases during Stage 2. At this point, the body prepares to enter deep sleep. Stages 3 and 4 are deep sleep stages, with stage 4 being more intense than Stage 3. These stages are known as slow-wave, or delta, sleep. If aroused from sleep during these stages, a person may feel disoriented for a few minutes. REM sleep is the portion of sleep when there are rapid eye movements.
Dreams occur during REM sleep. We typically have 3 to 5 periods of REM sleep per night. REM sleep is characterized by a number of other features including rapid, low-voltage brain waves detectable on the electroencephalographic (EEG) recording, irregular breathing and heart rate and involuntary muscle jerks. A night terror is a sleep disruption that seems similar to a nightmare, but with a far more dramatic presentation. A nightmare is merely a frightening or unpleasant dream. If you asked Sigmund Freud "why do we dream? " he would say our dreams are a secret outlet for these repressed desires.
Freud used dream analysis to interpret the underlying language of dreams - which is very different from normal conscious thinking. I agree with this theory because in our society, people have the tendency to hold back their urges and repress their impulses. However, these urges and impulses ultimately must be released in some way; they have a way of coming to the surface in disguised forms. Most urges and impulses are usually released through an individual's dream. One major class of drugs are stimulants, drugs that stimulate the brain and central nervous system, speeding up communication between the two.
They usually increase alertness and physical activity. They include drugs such as amphetamines, cocaine, crack and some inhalants like amyl or butyl nitrites. Furthermore, depressants slow down the activity of the brain and nervous system, slowing down the communication between the two. For medical purposes they can calm nerves, relax muscles and useful for sleeping disorders such as insomnia. Some depressants include cannabis, inhalants, and morphine. Hallucinogens interfere with the brain and central nervous system in a way that results in radical distortions of a user’s perception of reality.
Profound images, sounds and sensations will be experienced, but they will not actually exist. These are vivid hallucinations. Some examples of hallucinogens are LSD, PCP, and Magic Mushrooms (Psilocybin). Dream sharing is an extremely interesting concept and I think it's totally possible. Dream sharing is possible because all people share some kind of mental link (even though we're not consciously aware of it). The Noosphere is the idea that all human thought exists on its own plane so to speak. It's almost a collective unconscious of sorts.
We all have access to it, but aren't consciously aware that we do or how we do. However, it is a very challenging goal; to share a dream. You really need to have friends that have a passion for lucid dreaming, and the skills to back up that passion. This is a totally next-to-impossible task for the casual enthusiast but well worth it when you finally connect and have this taste of objective mutual dreaming. A topic that has always bewildered me with curiosity is the idea of dreaming within a dream. We all saw that this was more than possible in the outstanding movie Inception.
However, is it actually possible in the real word and if so, what does it mean? Having a dream within a dream may be safer and more acceptable way to express material from your unconscious. The dream within a dream protects you, the dreamer from waking up. Such dreams often reflect a hidden but crucial issue which you need to acknowledge and confront. Researchers have developed technology that leads them to believe reading a person’s dreams will one day be possible. Extraction is the art of infiltrating the mind of any person to steal their secrets.
Extraction works through a process called dream-sharing— manufacturing the world of the dream and bringing the subject into that world, which feels completely real as long as they are in it. Those who commit extraction are called extractors. I don't quite know if I believe in this theory of extraction, perhaps if I saw it occur with my own two eyes I would. Are our dreams really vulnerable to manipulation? For extraction to be a viable means of employment, the dreams themselves must offer up something worth stealing — personal ideas. In general terms, the dreaming mind’s idea-generation process is largely autobiographical.
An experience during the day gets incorporated, often in a seemingly odd way, with a dream, leading the dreamer to make an association that is almost always personal. Inception is a bit different than extraction, but both go hand in hand. In Inception, dream time runs much slower than real time, and there is a scaling effect, such that if you dream within a dream, time passes even more slowly. Until the right technology is created to ensure that inception and extraction are possible, I am lead to believe that it is merely lucid dreaming and nothing more.