Epilepsy is one of the common diseases that we see in everyday life. It is not uncommon to see a person getting an epileptic fit/ convulsions in a public place or to see parents/teachers rushing to the physician to report such cases in children.

In epilepsy, there is a sudden transitory disturbance in brain, leading to sudden generalized convulsions of the whole body, involving all the four limbs, including the face, all at once (i.e. disturbance in motor function of the brain), called generalized/major/grand mal epilepsy. Or, there is convulsion of a part of the body, e.g. one of the limbs, or a part of the limb, say an arm, hand, foot, etc., or muscles of the face/ eye only. In some cases, however, these convulsions may spread first on the same side of the body, followed by similar symptoms on the other half of the body. In which case, the whole body gets involved, and this is called focal or Jacksonian epilepsy.

In many cases, especially in children, there may be only momentary / transitory unconsciousness (i.e. disturbance of consciousness in the brain) called petit mal epilepsy.

Likewise, some disturbance may occur to affect special sensations in the brain, i.e., sensation of sight (when the patient experiences dots or momentary bright lights), of hearing (when he hears odd noises), of smell or taste (i.e. abnormal/ unpleasant sensations of smell or taste etc.) Even sensations in the internal organs (visceral) may be involved in epilepsy, and the patient may feel discomfort in the upper and middle part of his abdomen (epigastrium), and this may also be associated with nausea/vomiting. Sensory sensations may also be involved, and the patient may feel pricking, burning, tearing etc. sensations in any part of the skin of the body.

In still other cases of epilepsy, say temporal lobe epilepsy, there may be emotional disturbances so that the patient may feel markedly frightened or terrorized etc. Or, there may be a disordered sense of the body, so that he feels as if one of his limbs, such as his arm, is getting smaller and smaller. He/she may even feel that the whole limb has disappeared. Likewise, the patient may feel that a part of the body is becoming larger and! or appearing in different forms/ shapes. There is a feeling of unreality, depersonalization and the patient may sink into a dream-like state. There may even be hallucinations of smell or taste in a case of temporal lobe epilepsy, which is one of the common focal epilepsies.

In general, any of the above clinical manifestations relating to the involvement of special senses or consciousness etc. may occur alone, or may be quickly followed by generalized/focal convulsion/ s, involving the motor function of the brain.

When such manifestations occur immediately before an attack of convulsions these are called 'aura'. These clinical manifestations are highly significant as they give a clue to the involvement of a specific area in the brain represented by them. The patient must in such a case be questioned, and symptoms must be confirmed so that the lesion in the brain can be diagnosed clinically. It is often seen that when convulsions occur, these important symptoms get masked, and the patient remembers convulsions only, they being a major manifestation. Hence, awareness of such symptoms is of great importance so that the patients themselves reveal such vital information to facilitate the physician's task.

In a nutshell, in epilepsy, there is a disturbance in various functions of the brain relating to motor function, consciousness, sensation, emotion etc., and its various clinical manifestations occur when any / some of the above functions an~ disturbed. And once one function is disturbed, disturbance of other functions may follow, depending upon the resistance/threshold of the patient concerned.

The resistance/threshold of the patient plays an important role in the involvement of various functions of the brain relating to epilepsy. In case the threshold/resistance is very high, none of the functions of the brain may be disturbed, i.e. there will be no attack of epilepsy, although the person is prone to epilepsy. However, in case the resistance is moderately high, only one function of the brain may be involved with no involvement of any other function of the brain. When the threshold/resistance is low/very low, disturbance of a function of the brain may quickly be followed by the involvement of other functions of brain, i.e., there may be an involvement of the functions of sensation, consciousness, motor function, etc. almost at the same time. The patient, after experiencing some disturbance relating to special senses (sight, smell, hearing etc.) may become unconscious, followed by generalized convulsions of the body (i.e. disturbance of motor function).