An overview of dreams
Adult humans sleep (at an average) for about eight hours every day. This period of time is divided into REM (rapid-eye-movement) sleep, which occurs periodically with NREM (non-rapid-eye-movement) sleep. The physiological state of REM occurs periodically with NREM (non-rapid-eye movement) about every ninety minutes, and lasts for about 20-30 minutes. Differences between NREM and REM can be measured using an electroencephalogram (EEG), electrooptogram (EOG), and electromyelogram (EMG), which measure brainwaves, eye-movement, and muscle tone, respectively. REM is categorized by high-frequency, low-amplitude, more irregular waves in EEG, rapid, coordinated movement in EOG, and weak EMG. During such kind of sleep, brain activation increases along with breathing and heart rates, and body movement is paralyzed.
Which part of the brain is responsible for dreaming?
REM Sleep
Although dreams and REM are not synonymous, most dreaming occurs during REM sleep. While as many as 70-95% of people awakened during REM remember their dreams, only 5-10% of those awakened during NREM report dreams. Areas Located in the Back Parts of the Brain Even though high rates of correlation were found between REM sleep and dreaming, recent studies have shown that areas in the back end of the brain are the root cause of human dreams. In order to arrive at this conclusion, researchers studied a patient who had recently had a stroke and had stopped dreaming shortly after. The researchers decided to monitor and examine the patient in order to discover which part of the brain was affected in other people with a similar condition.
After reviewing the brainwaves transmitted, the researchers realized that the patient's sleep was not disrupted, and she continued to have REM (rapid eye movement) sleep as normal. The researchers stated that areas in the back of the patient's brain were damaged, suggesting that these areas were the root cause of dreaming, not REM sleep. Other studies have shown that some of this region is involved in the visual processing of faces and landmarks, as well as the processing of emotions and visual memories, a logical set of functions for a brain area that would generate or control dreams. Because most dreaming does occur during REM sleep, however, the REM state can be thought of as one of the triggers for dreaming. The pons' paralyzing of the muscles is an important precondition for dreaming, since without that paralysis dreamers might act out their dreams (the effects of this problem can be seen in individuals suffering from REM Behavior Disorder). What will happen if we don't dream? Nothing. The description of the experiences of the patient (explained above) is the perfect example; areas in the back of her brain were damaged after a stroke and she was not able to dream. Even though she lost this function, she did not suffer any external or internal disorders, and continued to live a normal life. Why do we dream? As of now, there is no substantial explanation as to why we dream. Some studies suggest that dreaming has a direct relation to the emotions and experiences we do not express in our daily lives, but no theory has yet been scientifically proven. Resources The study can be found at http://news.bbc.co.uk/2/hi/healt...
A description of dreaming can be found at http://serendip.brynmawr.edu/bb/...
More interesting information about the parts of the brain involved in dreaming can be found at http://www.livestrong.com/articl... Hope this helps! Feel free to comment on this answer, A2A or PM me if there are any further questions, comments, or concerns.
