How can the physician distinguish between simple partial seizures and complex partial seizures?

In most cases, the two basic types of partial seizures are easy to differentiate.

Simple partial seizures

The signs or symptoms of simple partial seizures depend on the location of the seizure focus. Seizures involving the motor cortex usually are not difficult to diagnose. They commonly consist of rhythmic or semi-rhythmic clonic activity of the face, arm, or leg.

Seizures with somatosensory, autonomic, and psychic symptoms (hallucinations, illusions, déja vu) may be more difficult to diagnose. Psychic symptoms more often are a component of a complex partial seizure.

Complex partial seizures

Complex partial seizures (CPS) are one of the most common seizure types encountered in both children and adults.

By definition, all patients with CPS have impaired consciousness. The patient either does not respond to commands or responds in an abnormally slow manner. Simple staring and impaired responsiveness alone may characterize a CPS, but usually behavior during the seizure is more complex. Automatisms (involuntary motor activity) are common during the period of impaired consciousness. This behavior is quite variable. Common activities include:

  • facial grimacing
  • gesturing
  • chewing
  • lip smacking
  • snapping fingers
  • repeating phrases

The patient does not recall this activity after the seizure.

The length of CPS varies. They usually last from 30 seconds to several minutes. Their length helps to differentiate them from absence seizures, which usually last less than 15 seconds.

Most patients have some degree of postictal impairment, such as tiredness or confusion, after CPS.

Complex partial seizures may be preceded by a simple partial seizure (aura), which can serve as a warning to the patient of a more severe seizure to come. The nature of the aura may enable the physician to determine the cortical area in which the seizure is beginning.

Authored By: 
Gregory L. Holmes MD
Authored Date: