Professional and Linguistic Assessments Board (PLAB) Practice Exam

What symptoms characterize Jacksonian seizures?

1. Spreading sensory loss

2. Marching motor activity

3. Vision disturbances

4. Generalized tonic-clonic activity

The correct answer is: Marching motor activity

Jacksonian seizures are characterized primarily by "marching motor activity." This phenomenon involves a sequence of muscle contractions that typically starts in one part of the body and then spreads to adjacent areas, following a specific pattern. For example, a seizure might begin in a finger or hand and then progress to the arm, shoulder, and even the face on the same side of the body. This sequential activity reflects the organization of the motor cortex, where neighboring areas control adjacent body parts. The concept of Marching motor activity illustrates that Jacksonian seizures exhibit a clear and observable progression, helping both the patient and the healthcare provider understand the seizure's focal nature. It highlights that while the seizure's effects initially appear localized, they can expand in a stereotypical manner as it progresses, which is an important feature of these kinds of seizures as observed in many clinical presentations. These focal seizures may also evolve into more generalized seizures; however, the defining characteristic remains the "marching" aspect of motor activity.