Four Factors That Alter Your Sleep Architecture

Sleep architecture significantly determines how restful our sleep can be. Discover the consequences of a possible alteration in this architecture, aspects that can affect us all.

Written and verified by the psychologist Elena Sanz.

Last update: 08 April, 2023

Sleep is a crucial physiological process for your well-being. In fact, increasingly more professionals are echoing the importance of taking care of rest and promoting lifestyles that protect it. You must also ensure that your rest is good quality. For this, you need to know what sleep architecture is and what factors can alter it.

The relevance of this aspect lies in the fact that sleep isn’t the same at all times, but goes through various phases. Each of them fulfils specific functions that must take place if you want your body to function properly.

As a matter of fact, when the architecture of sleep is altered, your quality of rest is affected and you can deprive yourself of necessary processes.

Sleep architecture

Sleep architecture refers to the basic structural organization of sleep. It also includes its different phases and characteristics of each. Indeed, sleep can’t merely be conceptualized as a unique and homogeneous state that’s different from wakefulness. We must pay attention to its form and how it’s structured at each moment.

In a healthy adult, sleep is organized in cycles of about 90-120 minutes that are made up of different phases. Each complete cycle includes the following:

• Phase 1. This is a drowsy stage characterized by the presence of theta brain waves. You begin to feel drowsy, but you’re still able to perceive most environmental stimuli.
• Phase 2. At this stage, your brain activity slows down, your heart and respiratory rates decrease, and your muscle tone is reduced. At the brain level, delta waves are present in small amounts.
• Phase 3. By this time, sleep has become deeper and you’re less able to perceive stimuli from the environment. This stage is dominated by delta waves and lasts a couple of minutes.
• Phase 4. In this phase, you enter a state of deep relaxation. Both your blood pressure and heart rate remain low. There’s no muscle tone and, due to your sleep being deep, it’s difficult to wake up at this time. It’s a crucial phase in terms of restorative rest.
• REM sleep. In the previous stages, non-REM sleep predominates. This differs from the last stage, known as REM sleep. In this phase, your brain is extremely active and the characteristic rapid eye movements appear. It’s also the time when you dream. Due to the fact that it’s the final phase, it’s common to experience small micro-awakenings at the end of it.

Factors affecting sleep architecture

Each moment of sleep has its own characteristics and particularities, and all of them are necessary. As such, and in order to maintain optimal health, it’s vital that you complete each cycle of sleep.

If your sleep architecture is altered, the biological and psychological recovery and restoration processes that take place while you rest don’t occur properly, affecting your quality of life.

So, what factors can alter the architecture of sleep?

Age

Age is the main factor as sleep architecture varies remarkably throughout life. On the one hand, it’s known that babies have sleep cycles of about 50 minutes made up of only two phases: REM sleep and slow sleep. Newborns spend more time in REM sleep.

On the other hand, it’s been observed that, as we grow older, the amount of slow-wave sleep follows a non-linear progression. It reaches its maximum peak in adolescence. From that moment on, it begins to decrease. In the elderly, it’s extremely scarce.

These differences in sleep architecture that occur with age are natural and not pathological. However, they signify how your needs change over time and how your sleep structure adapts to them. For example, the fact that babies spend more time in the REM phase allows them to consolidate the huge amount of information and new learning that they’re acquiring from their environments. Indeed, it’s during the REM phase that this process occurs.

Your environment

Your environment can also impair the quality of your sleep and alter its structure. For example, environmental noise, exposure to light at night, and interruptions caused by other people can lead you to experience fragmented sleep which isn’t particularly restful.

For instance, you may get all the hours of sleep you need, but frequent awakenings (no matter how small) might prevent you from completing your natural sleep cycles. Therefore, it’s crucial to ensure you’re surrounded by the right conditions when you’re resting.

Internal factors

There are certain individual aspects that can also have an influence. One of the most common is stress. When this is present at high levels, it not only causes insomnia but also poor-quality sleep. This is due to the fact that the production of cortisol and hypocretins (substances that promote wakefulness) is stimulated, which makes sleep eminently light and fragmented, leading to early awakenings.

In addition, both physical and psychological health problems must be considered. In fact, pain (acute or chronic) and other symptoms of diseases that cause discomfort undoubtedly affect the ability to rest correctly. Similarly, various psychological disorders have been shown to alter the architecture of sleep in sufferers.

For example, ADHD appears to result in a higher percentage of sleep stage changes and lower sleep efficiency compared with individuals without the disorder. Similarly, sufferers of bipolar disorder appear to experience increased REM activity.

Drugs and substances

It shouldn’t be forgotten that certain substances can have an effect on sleep architecture.

For example, selective serotonin reuptake inhibitors have been associated with a possible suppressive effect on REM sleep. While methylphenidate used to treat ADHD appears to increase sleep latency. Similarly, drug use affects sleep architecture, both during periods of use and withdrawal.

Taking care of your sleep architecture is a healthy habit

In short, there are several factors that can alter the structure or form of sleep and have a negative impact. Moreover, poor quality sleep has been linked to daytime sleepiness, irritability, concentration problems, and impaired emotional and physical well-being. For this reason, it’s important that you take care of the quality of your rest and not just the number of hours you sleep.