A seizure is a sudden, uncontrolled electrical disturbance in the brain, causing temporary changes in movement, sensation, behavior, or consciousness. This abnormal electrical activity can manifest in various ways, from brief staring spells to full-body convulsions. Understanding the origins of these events is important to differentiate between actual seizures and other conditions that might appear similar. This article clarifies common causes of seizures and distinguishes them from conditions that do not.
Common Causes of Seizures
One of the most frequent reasons for recurrent seizures is epilepsy, a neurological condition characterized by a predisposition to generate unprovoked seizures. Physical trauma to the brain, such as a severe head injury, can disrupt normal brain function and lead to seizures. The immediate impact or subsequent scar tissue formation can create areas of abnormal electrical activity.
Vascular events like strokes, which result from interrupted blood flow to the brain, can also cause seizures. Both ischemic strokes (due to blockages) and hemorrhagic strokes (due to bleeding) can damage brain tissue, making it prone to uncontrolled electrical discharges. Brain infections, including meningitis (inflammation of the membranes surrounding the brain and spinal cord) and encephalitis (inflammation of the brain itself), can irritate brain tissue and trigger seizures.
A brain tumor, whether benign or malignant, can exert pressure on brain tissue or alter its electrical properties, leading to seizure activity. The abrupt cessation of certain substances, such as alcohol or sedative drugs, can induce withdrawal seizures. This occurs as the brain, accustomed to the depressant effects of these substances, becomes overactive when they are no longer present.
Significant imbalances in the body’s electrolytes, like very low sodium levels (hyponatremia) or very high calcium levels (hypercalcemia), can disrupt the electrical signaling within brain cells, causing seizures. In young children, high fevers can provoke febrile seizures, which are generally brief and resolve as the fever subsides. A prolonged lack of oxygen to the brain, often resulting from cardiac arrest or severe respiratory distress, can also lead to widespread neuronal damage and subsequent seizure activity.
Conditions Not Typically Causing Seizures
While some conditions may present with symptoms that resemble seizures, they do not involve the same abnormal electrical brain activity. Fainting, medically known as syncope, involves a temporary loss of consciousness due to a sudden drop in blood flow to the brain. Although some brief, minor jerking movements might occur during a faint, this is a result of the brain’s temporary lack of oxygen, not an uncontrolled electrical discharge within the brain itself.
Panic attacks, characterized by intense anxiety and physical symptoms such as rapid heart rate, dizziness, and trembling, can sometimes be mistaken for seizures. These events are rooted in the body’s “fight or flight” response and do not involve the disordered brain electrical activity seen in epileptic seizures. The individual remains conscious and aware, even if distressed, unlike many seizure types.
Psychogenic non-epileptic seizures (PNES) are another category of seizure-like events not caused by abnormal brain electrical discharges. These events are psychological in origin, often linked to stress or trauma, and manifest with physical symptoms that can closely mimic epileptic seizures. Despite their psychological basis, PNES are involuntary and real experiences for the individual.
Simple stress or general anxiety is not a common direct cause of seizures in otherwise healthy individuals. While severe psychological stress can act as a trigger for seizures in people already diagnosed with epilepsy, it does not induce a seizure in someone without an underlying predisposition or neurological condition. The brain’s electrical stability is generally maintained even under significant emotional strain.
Recognizing When to Seek Medical Attention
Prompt medical evaluation is important for anyone experiencing a seizure. Immediate medical attention should be sought in several situations:
- First occurrence of a seizure.
- Seizure lasting longer than five minutes (potential status epilepticus).
- Multiple seizures without regaining full consciousness between them.
- Difficulty breathing or failure to regain consciousness/alertness after a seizure.
- Injury sustained during a seizure (e.g., head trauma, fracture).
- Seizures in pregnant individuals.
- Seizures in those with pre-existing serious medical conditions (e.g., diabetes).
- Prolonged confusion or unresponsiveness after a seizure.