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Brain Activity

      The most important part of sleep that rejuvenates the body and brain is the rapid eye movement (REM) cycle. After an hour of sleep, the person moves into REM, which consists of extreme levels of dreaming and rapid eye movements. As a child, they experience longer periods of sleep compared to adults. On average, an adult experiences REM sleep every 90 minutes frequently switches back and forth, REM sleep to non-REM sleep, throughout the night. According to Cass, “without enough REM sleep [,] it becomes harder to focus on day-today activities” (par 12). People with insomnia have a decrease in the amount of REM sleep. In fact, the REM sleep stage is often associated with dreams and is responsible for keeping focus while awake and is though to improve and restore mental health.

      According to Brownlee in “Insomniac brains are both asleep and awake,” the brain may be active while one sleeps at night. Thanks to Clif Saper and Georgina Cano of Harvard University, they were able to test induced anxiety on rats. The controls involved a clean cage versus a dirty cage of another rat. Since rats are territorial, the animals exhibit signs of stress and have trouble falling back to sleep. In fact, if they do fall asleep, they have many cases of waking up in the middle of the night. After looking at the rats’ brains, the cortex was found to be active during their sleep, which is only supposed to be active when awake. However, the ventral lateral preoptic area was on as normal and this appears to make the rats’ brain neither awake nor asleep. In addition, Cano has been reported that insomniacs are awake while they sleep, but their brain waves show that they are asleep (qtd. in Brownlee 1). This gives additional support that insomniacs' brains are working twice as much while they sleep and more reasons that many people might become more tired then the night before because of certain factors such as stress.

      From “Insomnia Subtypes and their Relationships to Daytime Sleepiness in Patients with Obstructive Sleep Apnea,” Chung wanted to conclude if there was a relationship between insomnia subtypes and daytime sleepiness. In Chung’s report, he starts a test that shows the affects of patients with Obstructive Sleep Apnea (OPA). People who have obstructive sleep apnea usually have insomnia. He begins by testing the differences between patients with sleep onset insomnia, sleep maintenance insomnia and no insomnia symptom. Chung believes that sleep onset problem is caused by hyperarousal and sleep maintenance difficulty. The test consists of questionnaires, polysomnography and Multiple Sleep Latency Test (MSLT). From 157 obstructive sleep apnea patients, it has been found that there is an increase in elecgromyogram, heart rate, body temperature, urinary cortisol, adrenaline excretion, and metabolic rate. From the data values, people with severe sleep onset insomnia tend to have higher sleep latencies and lower ESS scores. It was shown that there were more male patients then female with a 44.5 ± 9.6 years of age. Most of the patients had a body mass index of 27.8 ± 4.5 kg/m² (462). Over 42% of patients with OSA had one or more insomnia symptoms. In the end, there is a dependent relationship between insomnia subtypes and daytime sleepiness. This proved that most OSA patients suffer from insomnia because of hyperarousal and would have frequently waked up at night. The results were similar to a previous test that tested patients with sleep maintenance problem.