Neural Conditions: Epilepsy/Seizures

Written by: Caroline Kim

July 27, 2024

Epilepsy is described by Cleveland Clinic as the  “long-term (chronic) disease that causes repeated seizures due to abnormal electrical signals produced by damaged brain cells”. These seizures are caused by bursts of electrical activity in the brain, which ensues changes in awareness/consciousness, muscle control, sensations, behavior, and emotions (professional). It is important to note that epilepsy can affect anyone and is not limited to any specific group. Data shows that in just the U.S., as many as 3.4 million individuals have epilepsy of which 470,000 are children; worldwide, there are 65 million people with epilepsy (professional). 

Epilepsies are categorized by where they start in the brain, the individual's level of awareness, and the variance of muscle movement (professional). There are two main categories of seizures: focal onset seizures and generalized onset seizures. Focal onset aware seizures are described by Cleveland Clinic as starting in “one area, or network of cells, on one side of your brain”. Symptoms of focal seizures include awareness but changes in the senses, emotions, muscle jerking (often in the arms/legs), seeing flashing lights, and dizziness (professional). The counterpart is Focal onset impaired awareness seizures, in which the individual experiences a loss of consciousness, confusion, blank stare, and repetitive movements (professional). The latter of the two main seizure types is described as affecting “a widespread network of cells on both sides of your brain at the same time”, and can be further categorized as an absence seizure, atonic seizure, tonic seizure, clonic seizure, tonic-clonic seizure, or myoclonic seizure (professional). Cleveland describes absent seizures as a momentary loss of awareness with minor muscle movements (blinking, lip smacking, and chewing motions); atonic seizures are characterized by a “droop” in which muscle control is lost. On the flip side, tonic seizures carry a component of muscle stiffening in which the individual's body becomes tense. Clonic seizures involve muscle jerking, tonic-clonic seizures involve a combination of both muscle jerking and stiffness, and myoclonic seizures shock like twitching/muscle jerking (professional). Under the category of generalized seizures there are subcategories of infantile spasms where infants under the age of 6 months can experience as many as hundreds of seizures in a day; additionally febrile seizures affect children between the ages of 6 months and 5 years (Nationwide Children's). 

Seizures can be triggered for a variety of reasons including stress, sleep troubles, alcohol/drug use, illness, hormonal change, caffeine, dehydration, and flashing lights (professional). Cleveland Clinic states that in up to 70% of cases, the causes of seizures are unknown, but a few possibilities include genetics, head injuries, brain infections, mesial temporal sclerosis, immune disorders, developmental disorders, metabolic disorders, and brain abnormalities. Additional risk factors for epilepsy include premature birth, low birth weight, brain bleeds, cerebral palsy, and Alzheimer’s (American Association of Neurological Surgeons). Some tests utilized to diagnose epilepsy and seizures are electroencephalography (EEG), magnetic resonance imaging (MRI) brain scans, blood tests, computer tomography scans (CT or CAT), and lumbar punctures (spinal tap); treatments include anti seizure medications, diets, and surgeries (Nationwide Children's). Other treatment options may involve Vagus Nerve Stimulation, Responsive Stimulation, and Deep Brain Stimulation (NIH). 

Sources:

1. professional, Cleveland Clinic medical. “Epilepsy: What It Is, Causes, Symptoms, Diagnosis & Treatment.” Cleveland Clinic, my.clevelandclinic.org/health/diseases/17636-epilepsy. Accessed 27 July 2024. 

1. Nationwide Children's. “Epilepsy.” Causes, Symptoms, Diagnosis and Treatment, www.nationwidechildrens.org/conditions/epilepsy. Accessed 28 July 2024. 

1. American Association of Neurological Surgeons. “Epilepsy.” AANS, 15 Apr. 2024, www.aans.org/patients/conditions-treatments/epilepsy/. Accessed 28 July 2024. 

1. NIH. “Epilepsy and Seizures.” National Institute of Neurological Disorders and Stroke, U.S. Department of Health and Human Services, www.ninds.nih.gov/health-information/disorders/epilepsy-and-seizures. Accessed 28 July 2024.