Seizures in children, particularly those occurring during sleep, are a significant concern for many parents. A seizure represents a sudden, unregulated burst of electrical signals within the brain that temporarily disrupts normal brain function. When these events happen while a child is sleeping, they are referred to as nocturnal seizures.
Underlying Mechanisms in Children’s Brains
A child’s brain is in a continuous state of development, making it uniquely susceptible to disruptions in electrical activity. The brain’s nerve cells communicate through intricate electrical signals, and any interference with these connections can lead to a seizure. This developing nature means that the child’s brain may have different electrical activity patterns compared to an adult brain, contributing to a higher propensity for seizures.
Sleep stages significantly influence brain excitability and the likelihood of nocturnal seizures. Changes in the brain’s electrical activity during different sleep and waking stages are believed to trigger these events. Nocturnal seizures often manifest in the early morning hours, typically between 5:00 AM and 6:00 AM, or shortly after a child falls asleep.
While epileptic activity may sometimes lessen or even cease during REM sleep, specific patterns of brain activity during non-REM sleep can heighten seizure risk. Genetic predisposition also plays a role, as certain inherited gene variants can increase a child’s likelihood of experiencing seizures.
Specific Epilepsy Syndromes and Conditions
Several specific neurological conditions and epilepsy syndromes are commonly associated with nocturnal seizures in children. Benign Rolandic Epilepsy (BRE), also known as Benign Epilepsy with Centrotemporal Spikes (BECTS), is the most common focal epilepsy in childhood. Approximately 70% to 80% of seizures in children with BRE occur during sleep. These seizures typically involve twitching, numbness, or tingling in the face or tongue, sometimes accompanied by drooling or difficulty speaking, while the child may remain aware. This condition is considered “benign” because most children outgrow the seizures by their teenage years.
Another condition is Nocturnal Frontal Lobe Epilepsy (NFLE), now often termed sleep-related hypermotor epilepsy (SHE). This rare genetic disorder causes brief seizures that occur during sleep. These episodes can present with unusual behaviors such as screaming, laughing, or swearing, along with head or eye turning, leg kicking, or thrashing movements. Genetic mutations, including those in genes like CHRNA2, CHRNA4, and KCNT1, are linked to this condition, as are structural abnormalities like focal cortical dysplasia.
Landau-Kleffner Syndrome (LKS) is a rare epileptic encephalopathy that typically affects children between 3 and 9 years old. It is characterized by a regression in language skills and abnormal electrical activity in the brain, with seizures frequently occurring during sleep. While seizures are often focal motor and can generalize, “silent” electrical seizures during sleep are a notable feature.
Beyond these syndromes, structural brain abnormalities such as malformations, prior brain injuries, or tumors can also cause seizures by disrupting the brain’s normal electrical pathways. Scarring from past injuries, including those sustained at birth, can also elevate seizure risk. Beyond specific syndromes, genetic mutations, whether inherited or spontaneous, play a broad role in epilepsy by influencing proteins critical for brain signal transmission.
Factors That Can Provoke Seizures
Beyond underlying medical conditions, certain factors can provoke seizures in a child who is already susceptible. These factors do not cause epilepsy but can lower the seizure threshold, making an event more likely. One common trigger is fever, leading to what are known as febrile seizures. These typically occur in children between 6 months and 5 years of age when their fever rises above 100.4°F (38°C). Febrile seizures are generally distinct from epilepsy, though complex or prolonged episodes may slightly increase the risk of developing epilepsy later.
Sleep deprivation is another significant seizure trigger, especially for children prone to nocturnal seizures. Insufficient sleep can also hinder a child’s ability to manage stress, which can further contribute to seizure activity. Certain medications, both prescription and over-the-counter, can lower the seizure threshold. Antidepressants, particularly bupropion, and antihistamines like diphenhydramine, have been identified as common medications that can induce seizures in children.
Electrolyte imbalances, such as abnormal levels of sodium (hyponatremia or hypernatremia), calcium (hypocalcemia), or magnesium (hypomagnesemia), can also provoke seizures. Severe hyponatremia is a frequent cause of seizures in infants. Lastly, stress, though subjective, can increase both the frequency and susceptibility to seizures in children with epilepsy. Both acute stressful events and ongoing daily stressors can act as precipitating factors. Stress can also negatively impact sleep quality, creating a cycle that further increases seizure risk.