An Introduction to Sleep & it’s Effects

Sleep is the naturally recurring state of mind in which our consciousness is altered and awareness to external stimuli is reduced. Humans can spend around 1/3 of their life in this state. We can think of sleep as an almost ‘calming balm’ for our brains, and even our bodies. So, when individuals struggle with sleep, it can create a detrimental impact to their day-to-day functions. Sleep is one of the most fundamental layers of physical and mental health, and is broken down into stages.

5 Stages of Sleep

Stage 1:

Very light sleep; described as relaxed wakefulness, muscle tension lessens, slower brain wave patterns begin to occur, but we are still easily awakened

Stage 2:

Light sleep; the body is calmer, brain-wave patterns begin to occur which represent intermittent attempts to preserve awareness before we fall asleep. We are still easily awakened in this stage.

Stage 3:

Deep sleep; continued decrease in muscle tension, respiration, and heart rate. Very slow brain wave patterns begin to occur.

Stage 4:

Very deep sleep; this is the deepest stage of sleep, muscular energy is replenished, the brain is most inactive in this stage and immune system activation occurs. If you are awakened in this stage, you will feel disoriented and groggy and may not even remember it later.

Stage 5:

Rapid eye movement (REM); this is your dream sleep stage. Our brain-wave patterns in this stage are more similar to the state as when we are awake. In this stage our brains can process and save information we learned during the day.

Each stage of sleep has specific functions which supports relaxation, respiratory and circulatory regulation, tissue restoration, your immune system, learning etc. We progress from Stage 1-4 and then to REM Sleep about every 90 minutes.

Sleep and it’s Effects on Pain

  • 50% to 80% of people with chronic pain report poor sleep
  • Pain awakens us and disrupts our sleep
  • Being sleep deprived and disrupted sleep makes us more sensitive and vulnerable to pain
  • There can be a vicious cycle between disrupted sleep and chronic pain, maintaining and contributing to each other
  • Sleep deprivation has been shown to reduce pain threshold in controlled laboratory studies
  • Pain increases the amount of time in Stage 1 sleep (light sleep) and decreases the amount of time in Stage 4 sleep (deep sleep).

Pain interferes with sleep and disturbed sleep makes pain feel worse.  However, there are proven ways to improve your ability to allow your brain and your body to rest, to improve your sleep quality, to reduce your pain experience, and improve your quality of life.

Sleep and it’s Effects on TBI

Sleep disturbance is common following traumatic brain injury (TBI), affecting 30–70% of individuals, many occurring after mild injuries. Insomnia, fatigue, and sleepiness are the most frequent post-TBI sleep complaints. In addition, depression, anxiety, and pain are common TBI co-morbidities with substantial influence on sleep quality [1]

Where to start if you are struggling with sleep:

  • Begin to improve your sleep efficiency: This means reduce the amount of time in bed in which you are not sleeping. The goal is to associate your bedroom with sleep so use your bed for sleep only. If you don’t fall asleep within 20 to 30 minutes, or if you awaken during the night and don’t fall back to sleep within that time, don’t lie in bed tossing and turning. Instead, either go to another room or sit up in bed and engage in a quiet relaxing activity until you are drowsy.  Repeat this process as often as necessary until you fall asleep.
  • Remove all the clocks from your bedroom and resist checking the time on your phone
  • Regular exercise is a good idea to help with good sleep, but try not to do strenuous exercise in the 4 hours before bedtime
  • Create a proper sleeping environment. A cooler room with enough blankets to stay warm is best, and make sure you have curtains or an eye mask to block out early morning light and earplugs if there is noise outside your room.
  • Keep your daytime routine the same. Even if you have a bad night sleep and are tired it is important that you try to keep your daytime activities the same as you had planned. That is, don’t avoid activities because you feel tired. This can reinforce the insomnia.

Sleep is Unique

It is important to note that the above recommendations may not always work for everyone. Sleep is personal, and everyone has unique internal and external factors that affect their ability to sleep. These factors may include the type of work you do, the environment you live and sleep in, medical history, pain and function, lifestyle changes, etc. Our Clinician’s will always look at the individual as a whole and consider these factors when addressing sleep. Our Clinicians can also address an individual’s thoughts and feelings about sleep, as negative sleep thoughts can have a profound adverse affect on our sleep. If you or someone you know is struggling with sleep, please reach out to the team at Complex Injury Rehab for more information.

 -Bronwyn Westlaken 


[1] Viola-Saltzman, M., & Watson, N. F. (2012). Traumatic brain injury and sleep disorders. Neurologic clinics30(4), 1299–1312.