Types of seizures: a question and an answer

One of the readers of my blog sent me this question.  Thank you for the same. My answer follows.



I experienced something a few days ago. Without any warning as I was getting out of my chair, I hit the floor hard. I woke up after a few seconds and I was in a cold sweat, shaking and confused. I tried to get up, but, I couldn’t move for another few seconds. I am under a Neurologist’s care and he suspects complex partial seizures due to an abnormality on an EEG, but, he is not too sure. I went to the ER and everything seemed normal. I had another episode a few days later, the same thing, except this time I was just walking from one room to another and it happened. I have no idea what this could be. I have been accused of “spacing out” and I have callouses on my left finger knuckles. I never realized I was rubbing my fingers enough to get callouses. Is this seizure or just passing out? So confused!!


Dear so confused,

thank you for writing in. The episodes do sound suspicious for seizures though as my post indicates there is a broad differential of sudden unexplained loss of consciousness. Broadly speaking there can be three types of seizures:

1. Generalized seizures: as the name suggests in primary generalized seizures, the seizure starts off from the entire brain at the same time. So for example if you were to suffer a generalized seizure while the EEG is running, the EEG will show abrupt onset of epileptiform activity from the entire brain (both the hemispheres). Primary generalized tonic clonic seizures (at times referred to as grand mal seizures) are quite dramatic. If the person is standing when the seizure strikes, he shall suffer loss of body tone and fall down. Patients usually strike the ground hard and may suffer craniofacial injury as a result. There is complete loss of consciousness (so the patient shall be amnestic for the seizure). There is an initial tonic phase where in the body stiffens. This is soon followed by a clonic phase where in rhythmic inphase jerks of the limbs are observed. The patient may suffer a tongue bite or may suffer loss of bladder control during the ictus. The seizure itself lasts for about a minute or two and is followed by a more prolonged post ictal phase during which the patient has stopped shaking but is somnolent and difficult to arouse. The past ictal phase may last for about an hour with slow recovery to complete consciousness and a return to baseline. Of note the staring spells seen in children (also called Absence Epilepsy) is a type of generalized epilepsy.

2. Focal seizures/ partial seizures: as the name suggests these are seizures which arise from a focal area in the brain. Focal seizures are not accompanied by a complete loss of consciousness. Rather there is impairment in the level of consciousness/ awareness. Let me explain further. Let us assume that you are right handed. In people who are right handed, the left hemisphere is the dominant hemisphere and in the left temporal lobe is the speech center. Let us assume you suffer a focal seizure arising from the left temporal lobe. There shall be a sudden arrest in your behavior and you may stop speaking (since the left temporal lobe is now misfiring). If I speak to you at this time, you shall not reply back to me and you may not recall that I had spoken to you later. That said unlike a generalized seizure, you do not fall down and do not convulsive. Patients do display some non purposeful movements such as lip smacking and picking at the clothes. This is referred to an automatisms.  Prior to the onset of the seizure, patients may report an aura. The typical auras which are reported including an unpleasant smell (burning rubber), rising sensation in the tummy, a spinning sensation, unpleasant taste, psychic phenomena such as fear and so forth. This type of seizure is what we doctors refer to as a complex partial seizure (complex because awareness is impaired).

3. Focal seizure with secondary generalization: I think this is simple to understand now. The seizure starts off as a focal seizure but then spreads and crosses over to the other side of the brain and very soon (in a matter of milliseconds) the entire brain is showing the epileptiform activity. So initially you have a behavioral arrest and cannot speak but then very soon your entire body tenses up and you start convulsing.

There are other types of seizures some of which occur in the pediatric age group. At present I shall not dwell on them.

I hope I have been able to explain seizures to you in very simple terms. Follow up with your doctor. My very best to you.

Personal Regards,

Nitin Sethi, MD

Absence seizures–a few questions and some answers

One of my readers wrote to me today asking me a question about Absence seizures. She is a teacher and is concerned about a student in her care. I always feel teachers pick up Absence seizures far more frequently than parents. One of the reasons for this is that they spend so much time with the children (today most parents work and have limited time to spend with children). Teachers also are astute observers of children behavior and usually have a pretty good feel if something is wrong.

Here is what Ms. Lynn says, my answers to her query follow:


Ms J Lynn

Hi Dr Sethi,
I am a teacher and I have a student who is exhibiting these types of behaviors:
staring episodes, often says he can’t remember something we just talked about 30 seconds prior, he said recently that he feels like his “brain just wouldn’t work sometimes,” he has frequent meltdowns, easily agitated (but not aggressive), social (but very sensitive and easily hurt or offended), seems to have a low threshold for frustration and emotions escalate quickly, and he seems to overly react in situations when he feels physically hurt (if a ball hits him on any part of his body he is very upset, needs time to calm and he complains of feeling lots of pain).
Could all of these symptoms be related to some type of seizure activity?
Thank you for you help.

Dear Ms. Lynn,

                               thank you for writing in. Clinically seizures in children frequently look different from seizures in adults. In the case of Absence seizures, all the child may do would be to stare (hence the name staring spells), there are no gross convulsive movements seen (the child does not shake or have jerks of his arms and legs). During the time the child is having a seizure (staring), his brain is malfunctioning and hence the child is unable to recall things said or spoken to him during that time. Children may have hundreds of these small Absence seizures during the course of a day and hence you can imagine what follows. These children start slipping in their grades as compared to their peers.

I have to add here though, that not all staring spells in children turn out to be Absence seizures. As you are well aware there can be many behavioral and developmental problems in children which at times may mimic seizures (children who have Attention Deficit Disorder too do not do well in school etc).

I would advise you to report your observations to his parents. The child can be assessed by a pediatrician and further investigations if needed can then be carried out.

I sincerely appreciate your concern for your student. Teachers lay the foundation of our society. I am what I am today because of the hard work of my teachers and my parents.

Personal Regards,

Nitin Sethi, MD

Absence seizures and staring spells

Let us talk about another kind of childhood seizures called Absence seizures or at times Petit Mal seizures. Childhood absence epilepsy as the name suggests starts off in childhood. The seizures are subtle and thus may escape detection from even doting parents. Most of the time, it is the teachers in school who first report that the child at times is noted to “stare” or “daydream”. At times the school grades start falling and this brings the child to medical attention.

Absence seizures as the name suggests are short duration seizures where-in the child is “absent”. By that I mean that for the short time (few seconds to a minute)  during which the child is having a seizure, he or she is not aware of the immediate surroundings. This is because even though an Absence seizure is brief, it is a generalized seizure (meaning the whole brain has a seizure and thus malfunctions for that few seconds). It is different from a generalized convulsion in that you do not seek the violent shaking movements of the arms and legs. Thus it is subtle and may escape detection in the earlier years.

Absence seizures need to be treated. The reason for this is that the seizures are frequent, at time hundreds in a day and these frequent seizures impair the cognitive development of the child. The diagnosis is relatively straight forward and your physician might make it on the basis of a good history. An electroencephalogram (EEG) study may shown the characteristic EEG pattern of Absence epilepsy confirming the diagnosis. An imaging study is usually not needed unless there are some atypical features in the presentation.

Once the diagnosis is made, Absence seizures can be readily controlled with anti-epileptic drugs. Two drugs are commonly used for this kind of epilepsy: ethosuximide and valproate. Children usually do not need to be on anti-epileptic drugs for prolonged length of time and they usually outgrow these seizures by the time they reach the age of 17.

Dr. Sethi