Understanding Epilepsy and Seizures

A seizure is a neurological event caused by a sudden surge of abnormal electrical activity in the brain’s neurons. It may indicate an underlying neurological disorder or dysfunction within the brain.

What Is a Seizure?

Under normal circumstances, neurons in the brain generate small, controlled electrical impulses that enable highly coordinated communication between different regions of the brain.
A seizure refers to a neurological event caused by a sudden burst of abnormal electrical activity in the brain’s neurons. Its occurrence may indicate underlying dysfunction or disease within the brain.

Mechanism of Seizure Onset:

In certain cases, neurons in a specific region of the brain begin to produce abnormal electrical discharges without external stimulation. These abnormal impulses may spread locally or diffusely to other areas, activating otherwise inactive neurons.
This synchronous overactivation disrupts normal brain coordination, leading to the symptoms observed during a seizure.

Symptoms of Seizures

The symptoms, duration, and severity of a seizure vary depending on the affected brain region and the type of seizure.

Common manifestations include:

Motor symptoms: Sudden violent shaking or convulsions, tonic–clonic muscle stiffness, or loss of motor control. Severe seizures may cause urinary or faecal incontinence.
Sensory disturbances: Tingling, numbness, pain, hallucinations, or visual disturbances.
Autonomic changes: Fluctuations in heart rate, sweating, or nausea.
Altered consciousness or behaviour: Staring episodes or confusion.
Loss of consciousness: Some seizures lead to complete unresponsiveness, followed by profound fatigue.

Typical Features of a Seizure

Sudden onset: Seizures usually occur without warning.
Short duration: Most last from a few seconds to a few minutes.
Reversibility: Normal brain function typically resumes afterwards, although patients may experience confusion or tiredness following an episode.

Types and Severity of Seizures

As described above, symptoms depend on which part of the brain is affected, and the severity can vary significantly.

1. Focal (Partial) Seizures

Focal seizures originate from a specific region within one hemisphere of the brain and affect only that side. According to the level of consciousness, they are categorised as:

Focal aware seizures: The patient remains conscious during the episode, often experiencing localised muscle twitching, unusual sensations, or vertigo.
Focal impaired awareness seizures: Consciousness is altered. The patient may exhibit automatisms such as staring, slow responses, confusion, or brief loss of awareness.

2. Generalised Seizures

Generalised seizures involve both hemispheres of the brain simultaneously, causing widespread, intense symptoms:

Absence seizures: Brief loss of consciousness lasting a few seconds, often mistaken for daydreaming.
Myoclonic seizures: Sudden, brief muscle jerks.
Atonic seizures: Sudden loss of muscle tone leading to collapse.
Tonic–clonic seizures: Characterised by abrupt loss of consciousness, muscular rigidity, convulsions, and sometimes urinary or faecal incontinence.

A seizure represents a temporary disturbance of normal brain electrical activity that can result in tonic–clonic movements and impaired consciousness.

What Is Epilepsy?

Epilepsy is a chronic neurological disorder characterised by recurrent, unprovoked seizures occurring over time.

The underlying cause of epilepsy lies in a long-term disruption of the brain’s electrical activity, leading to recurrent, spontaneous, synchronised discharges among neurons.

According to the World Health Organisation (WHO), epilepsy affects approximately 50 million people worldwide, making it one of the most common and significant neurological disorders. It can occur across all age groups and has major implications for public health and quality of life.

Although epilepsy is common, public understanding of its causes, symptoms, diagnosis, and management remains limited.

A formal diagnosis of epilepsy must be based on the pattern, frequency, and underlying cause of seizures, alongside diagnostic test results, and should be made by a qualified medical specialist.