Stages of sleep
The stages of sleep can be largely classified into REM sleep and non-REM sleep. In these two stages, the human brain and body react differently. Depending on brain activity as well as eyeball and muscle movement patterns, the stages of sleep can be detailed into four stages (Sharma, 2022).
- Stage 1 (Non-REM)
The first stage can be seen as a drowsy stage. At this stage, the body does not fully relax, but the brain and body’s activity slow down for a while. In this sleep phase, sudden muscle contraction called hypnic jerk can occur. The first stage can be easily broken if the surroundings are disturbed (Sharma, 2022).
- Stage 2 (Non-REM)
The second stage can be seen as a mild sleep state. At this stage, reactions such as muscle relaxation, eye movement stops, and heart rate slowness occur. In the second stage, the body becomes calmer than in the first stage and becomes insensitive to external stimuli (Sharma, 2022).
- Stage 3 (Non-REM)
Stage 3 is a deep sleep state. At this stage, the body becomes more relaxed and muscle activity and eye movements disappear. During this period, the brain produces slow waves called delta waves, which are difficult to break due to external stimuli. Experts believe that the third stage is related to restoring the body and strengthening the immune system (Sharma, 2022).
- REM
The REM sleep phase increases brain activity, which can speed up heart rate, respiratory rate, and eye movements similar to waking conditions. However, muscles are temporarily unable to move. It is known that people can dream the most vivid and intense dreams at this stage. People can dream at all stages of sleep, but it occurs rarely at the non-REM stage (Sharma, 2022).
The reasons for dreams
Many sleep experts have yet to find an exact answer to why people dream when they sleep. Dreams are closely related to human brain activity. Neuroscience and psychology experts continue to study what changes occur in the human brain during sleep. However, the human brain has the most complicated and mysterious part of numerous scientific studies. Therefore, even if research on dreams continues, it will be difficult to find an answer to the exact reason for dreaming (Nichols, 2018).
- Memory classification and integration
We accumulate a lot of memories every day. It is too much to remember each of these memories vividly. So, our brains sort and integrate the information we get, remembering what’s important and erasing information that’s not helpful. This process appears when you dream (Nichols, 2018).
- Psychical cure
We face various emotional situations in real life. Our brains face emotional problems through dreams, allowing us to deal with these emotions in new ways and new perspectives that we have not normally thought about. This process helps to identify and resolve specific causes of emotions, especially anger, fear, and sadness (Nichols, 2018).
- An unconscious expression
People’s unconscious desires, thoughts, and wishes can appear in their dreams. This process assists in confronting and resolving emotions and thoughts that are difficult to confront and resolve in real life (Nichols, 2018).
Do dreams affect the quality of sleep?
It’s normal to dream when you sleep. In general, dreaming does not negatively affect sleep quality. However, nightmares can interfere with mental health and lower the quality of sleep. Nightmares make it difficult for people to fall asleep again. This ruins people’s sleep time, and their sleep cycle, making them tired during the day (Conte et al., 2021).
Why do we forget our dreams easily?
Many people quickly forget their dreams. It is not known exactly why dreams are hard to remember and quickly forgotten. The most compelling explanation is that the cerebral cortex, an area of the brain that is activated when dreaming, quickly forgets unconscious thinking. It is information that is not important to remember the contents of the dream one by one, and in general, the memory is quickly lost because the dream is an unconscious area. Most dreams disappear, but there can be memorable dreams. The dream attracts attention because it is impressive and activates the memory-promoting area of the brain, the dorsolateral prefrontal cortex. The increased activity of DLPFC increases the likelihood of remembering the dream (Hartmann, 2011).
Conclusion
Sleeping well is very helpful for maintaining mental health as well as the body. Lack of sleep, depression, and sleep disorders can cause nightmares that negatively affect sleep quality. To avoid nightmares, regular living, good sleep hygiene, and medication for sleep disorders can help. Research on why we dream when we sleep is still ongoing and no answer has been found. Dreams are spaces that reflect unconscious thoughts and emotions. The reason why there is no answer to the reason for dreaming may be because it is deeply related to mysterious human brain activity.
References
Sharma, K. (2022). Sleep Cycle: Four Stages To A Good Sleep. [online] TheHealthSite. Available at: https://www.thehealthsite.com/photo-gallery/sleep-cycle-four-stages-to-a-good-sleep-909986/sleep-5-2-909991/ [Accessed 23 September 2022].
Nichols, H. (2018). Dreams: Causes, types, meaning, what they are, and more. [online] www.medicalnewstoday.com. Available at: https://www.medicalnewstoday.com/articles/284378#causes [Accessed 23 September 2022].
Hartmann, E. (2011). Ask the Brains. Scientific American Mind, [online] 22(2), pp.70–70. doi:10.1038/scientificamericanmind0511-70/ [Accessed 23 September 2022].
Conte, F., Cellini, N., De Rosa, O., Rescott, M.L., Malloggi, S., Giganti, F. and Ficca, G. (2021). The Effects of Sleep Quality on Dream and Waking Emotions. International Journal of Environmental Research and Public Health, [online] 18(2). doi:10.3390/ijerph18020431/ [Accessed 23 September 2022].
