NORMAL ELECTRICAL
FIRING PATTERNS OF CORTICAL NEURONS AND THE
ORIGIN AND SPREAD OF SEIZURES
The collective electrical activity
of the cerebral cortex can be monitored by electroencephalography (EEG).
Normal
cortical electrical activity reflects the summation of excitatory and
inhibitory actions, which is modulated through feedback circuits. Thalamic inputs to the cortex can
drive electrical excitability; the
midbrain can provide inhibitory control over this process. Repetitive cortical
activation can dampen inhibition, enhance excitatory feedback circuits, and
recruit repetitive excitatory circuitry in adjacent cortical neurons. These
self-perpetuating excitatory feedback circuits can initiate and spread seizure activity.