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Epilepsy made simple

Epilepsy Made Simple

Prof. Dr. U. Gauthamadas
MD PhD DPM DCBD
Neuro Behavioural Medicine Specialist
Website: www.docgautham.com

Epilepsy, sometimes called "fits” or "seizure disorder," refers to a sudden surge in electrical activity in the brain that may cause momentary loss of consciousness, staring spells, repetitive movements, or convulsions involving the entire body. To understand why seizures occur and why they induce a variety of physical manifestations, it is important to understand normal brain function as well as what causes cells in the brain to function abnormally.

The brain is the most complex organ in the human body, and the only evidence most of us have that it is functioning properly is the collection of abilities we so often take for granted. We wake, we walk and talk, our hearts beat, we taste, we breathe, and we think, all as a result of the highly coordinated electrical and chemical activity within and between the cells that make up our brains.

Occasionally, however, these cells function abnormally—they misfire. In some people, brain cells misfire repeatedly and this causes changes in behavior, sensation, or motor function. These occurrences are called seizures, and a person who has experienced two or more seizures is said to have epilepsy.

The brain is made up of three main structures: the cerebrum, the brain stem, and the cerebellum. The cerebrum is the largest of the three structures and is responsible for thinking feeling and action. The brainstem is responsible for functions that are responsible for life including consciousness, heart beat, respiration, etc. The cerebellum is responsible for balance and coordination.

The cerebrum is the highly folded, neuron-rich outer layer of at the top of the brain that is referred to as gray matter. The grey matter can be further divided into four functionally distinct lobes: frontal, parietal, occipital, and temporal. The frontal lobe is most often associated with personality, motor function, and execution of activities; the parietal lobe is involved in sensory interpretations and in creating associations among experiences; the occipital lobe processes visual information; and the temporal lobe is involved in memory, speech, and auditory and olfactory functions.Seizures can occur anywhere in the brain, and symptoms manifest depending on where they occur. A seizure that begins in the region of the frontal lobe that is responsible for motor control may cause rhythmic jerking movements of a finger, a hand, an arm, a leg, or the face. Seizures originating in the region of the parietal lobe responsible for sensory perception in the extremities may cause a burning or tingling sensation in the arms, hands, legs, or feet. Seizures originating in the temporal lobe may cause sudden abdominal discomfort, palpitation, flushing of the face, and feelings of fear. Seizures originating in the occipital lobe may cause flashes of light to be seen. These are all called partial seizures as they occour in one part of the brain.

Partial seizures are seizures that begin in one area, or focus, of the brain. They may or may not affect consciousness, depending on where in the brain they occur and the specialized brain structures they might involve. A partial seizure that does not affect consciousness is called a simple partial seizure. A partial seizure that alters consciousness is called a complex partial seizure.

All these manifestations of seizures are transient and last for a few seconds to a few minutes (usually less than 5 minutes).   They do not affect consciousness and the affected person is fully aware of what is happening. However, seizure activity that begins in one part of the brain can spread through the vast networks of neurons in the brain, producing more widespread seizure activity which involves the entire brain. When this happens, the person loses consciousness, falls to the ground and has convulsions involving the entire body.  A seizure that begins focally, meaning in one area, and progresses to involve the entire brain is classified as a partial seizure that becomes generalized.

Complex partial seizures may begin as simple partial seizures and then progress, or spread, to other areas of the brain, where they may affect consciousness or cause staring, confusion, or loss of alertness. In some cases, they also cause aimless movements, such as lip smacking or picking at clothes, the repetition of words or phrases, or inappropriate laughter etc.,

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