If you're a new parent, you may have experienced the surprise of seeing your baby twitch or jerk while they're supposed to be peacefully sleeping. It can be a bit alarming at first, but rest assured, these movements are perfectly normal and harmless. In fact, they are often attributed to a phenomenon called myoclonus. In this article, we'll dive into the world of infant sleep patterns and explore what myoclonus is, why it happens, and how you can ensure your little one gets the best sleep possible.
Understanding Sleep Myoclonus
Myoclonus is a clinical term used to describe sudden and involuntary muscle spasms. In the case of babies, there are two main categories of myoclonus to consider: physiologic myoclonus and pathologic myoclonus.
Physiologic myoclonus refers to muscle spasms that have a physiological explanation and are considered normal. Hiccups are a common form of physiologic myoclonus that you may have noticed in your baby. These types of spasms are nothing to worry about and are often a sign of healthy development.
On the other hand, pathologic myoclonus is abnormal and may indicate an underlying condition. However, it's important to note that most of your baby's muscle spasms will fall under the physiologic category, which is completely normal and expected.
Is Your Baby's Twitching Normal?
If your baby experiences jerky movements primarily during sleep, there's typically no cause for concern. Benign neonatal sleep myoclonus is limited to the hours spent sleeping, which should be around 12 to 18 hours per day for babies under one year old. As long as the twitches don't disrupt their deep sleep or prevent them from getting the rest they need, everything is fine.
If your baby twitches right before falling asleep, it's also nothing to worry about. These twitches, known as hypnic jerks, are a type of myoclonus that occur during the transition from wakefulness to sleep. It's a common phenomenon experienced by both babies and adults.
However, if your baby twitches after waking up, it's advisable to consult a doctor. These twitches may be a sign of infantile spasms, which are brief seizures characterized by the sudden stiffening of the body and bending of the arms, legs, and head. Infantile spasms rarely occur during sleep and should be evaluated by a healthcare professional.
The Science of Infant Sleep
Sleep is crucial for infants' growth and development. Although there is still much to learn about the complexities of sleep and the brain, we know that young infants require a significant amount of sleep. In fact, healthy children will have spent more time asleep than awake before their third birthday.
Twitching during sleep is completely normal for infants, and it may vary depending on their age. Here's a breakdown of sleep twitching patterns from newborns to one-year-olds:
- The first few weeks: During this stage, you'll notice various movements like sucking, smiling, frowning, limb-twitching, and irregular breath cycles. These behaviors are all part of normal sleeping patterns for newborns.
- From 1 to 6 months old: Babies in this age range quickly enter REM (rapid eye movement) sleep after closing their eyelids. REM sleep is characterized by rapid eye movements and muscle twitches. Therefore, you're likely to observe twitchy behavior shortly after your baby falls asleep.
- By the 1st birthday: By the time your baby reaches one year old, their sleep patterns will have become more regulated. They will experience longer stretches of uninterrupted sleep, and you may notice fewer myoclonus-related twitches.
Experts agree that sleep plays a vital role in an infant's overall well-being and future development. Surprisingly, these twitches are an integral part of their neural development.
The Importance of Sleep Myoclonus
Rather than being a sign of sleep disturbance, researchers believe that sleep myoclonus indicates significant developmental progress during the first year of life. The most common areas affected by these twitches are the feet and legs, neck, face, cheeks, and arms and hands.
During sleep, your baby's brain is actively forming neural connections that will enable them to perform various actions as they grow. These twitches are physical manifestations of the brain exploring and building these connections. If you pay close attention, you may notice a correlation between your baby's daytime activities and the body parts that twitch while they're asleep.
For example, if your baby has been practicing finger painting with sweet potato puree, you may notice more twitching in their hands during sleep. These movements are all part of the natural developmental process.
Understanding Myoclonus vs. REM
Do babies dream? The answer is yes! REM (rapid eye movement) sleep occurs in humans of all ages and is the stage of sleep associated with dreaming. Babies spend approximately half of their sleeping hours in REM sleep, which is essential for learning, memory retention, and overall brain development.
Both myoclonus and REM involve involuntary movements. However, REM specifically refers to a phase of sleep where the eyes display rapid-paced movement. While myoclonus often occurs during REM cycles, it is not synonymous with REM sleep.
When Should You Be Concerned?
While most twitching and spasms are normal in infants, there are instances where more severe spasms may indicate an underlying issue. Here are some red flags to watch out for:
- Convulsions while awake: If your baby experiences spasms while awake, it's important to consult a healthcare professional. While it may not be a cause for immediate concern, certain types of spasms can be associated with abnormal infant behavior and should be evaluated.
- Pauses in breathing: If your baby's spasms are accompanied by pauses in breathing, it could be a sign of sleep apnea. In such cases, it's advisable to seek medical attention to rule out any neurological or physiological breathing issues. However, it's worth noting that pauses in breathing during sleep are often normal for infants.
- Fever: Febrile seizures can occur in babies as young as six months old when their temperature suddenly rises due to illness. Most febrile seizures last only a couple of minutes, but complex febrile seizures can last up to 15 minutes or occur in recurring episodes. If your baby experiences both a high temperature and convulsions, it's important to contact a healthcare professional.
While these instances are relatively rare, it's crucial to seek medical advice if you notice any concerning symptoms or behaviors in your baby.
Paroxysmal Nonepileptic Events and Epilepsy
Two common conditions associated with severe spasms in infants are paroxysmal nonepileptic events (PNE) and epilepsy.
Paroxysmal nonepileptic events refer to sudden and intense spasms that may be more severe than typical myoclonus twitches. Approximately 9% of newborns experience PNE, but only some will be diagnosed with an underlying disorder like epilepsy. While the exact cause of PNE is unknown, studies have found a correlation between maternal smoking during pregnancy and the incidence of PNE in newborns. Most cases of PNE are benign and will resolve as the baby grows, with no long-term health consequences.
Epilepsy is a common concern for parents who witness their child twitching during sleep. If you suspect that your baby's twitches may be a sign of epilepsy, your pediatrician can perform various tests, such as white blood tests, imaging tests, and electroencephalography, to rule out the condition. However, it's important to note that the incidence of epilepsy in children is extremely low, affecting only 0.6% of kids between the ages of 0 and 17.
While observing your baby twitching in their sleep may initially cause concern, it's generally a natural occurrence associated with myoclonus and an essential part of their neural development. However, if the twitching extends beyond sleep or is accompanied by other concerning symptoms, it's always best to consult with a healthcare professional to ensure your baby's well-being and development are on track.
Sources:
- Myoclonus Fact Sheet
- On the development of sleep states in the first weeks of life
- Sleep physiology and sleep disorders in childhood
- Infant sleep and its relation with cognition and growth: a narrative review
- What’s going on when babies twitch in their sleep?
- Benign myoclonus of early infancy
- Spontaneous and apnea arousals from sleep in preterm infants
- What Is a Febrile Seizure?
- Paroxysmal disorders in infancy and their risk factors in a population-based cohort: the Generation R Study
- Is it really a seizure? The challenge of paroxysmal nonepileptic events in young infants
- Epilepsy Fast Facts
- Transient benign paroxysmal movement disorders in infancy