The immediate factors that provoke a given seizure are complex, and seizures are rarely predictable. Seizures may be triggered or irritated by a variety of mechanisms. The most common trigger is, whether intentionally or unintentionally, and can also influence seizure frequency.
Some studies indicate that emotional stresses such as
may cause seizures, especially if combined with fatigue or chronic sleep loss. Practicing relaxation techniques and treating disorders contributing to sleep loss (such as deep sleep apnea) may decrease seizure frequency. Melatonin has been successfully given for sleep loss in children. Unpredictable changes in metabolic factors such as :
can also contribute to seizures. In contrast, reflex epilepsy is a condition in which seizures can be provoked by an external stimulus (flashing lights) or, occasionally , by an internal mental process (mathematical calculation). Reflex seizures are fairly predictable in response to specific stimuli, and may coexist with spontaneously occurring seizures. They are epileptic, not psychogenic, and may occur as either focal-onset or primary generalized seizures. An EEG response to repetitive light stimulation is called “photo-sensitivity” and is seen in about 25 percent of individuals with primary generalized epilepsy.
Reflex epilepsy usually begins in childhood and may be outgrown by adulthood. Triggers in pattern-sensitive epilepsy may include circles, stripes or other patterns, usually of high contrast. TV and electronic screen games have caused reflex seizures. This may be due to the flicker frequency of the screen and distance from it, as well as images. European TV has a lower flicker frequency and is therefore more apt to trigger seizures. Individuals who experience their first seizure while playing electronic screen games are found to be photosensitive.
Other types of sensory stimuli, such as light touch, tapping or soaking in hot water can be associated with reflex seizures; auditory stimuli are less common triggers of seizures. Another type of reflex epilepsy that is even more intriguing and unusual is that triggered by complex actions or mental processes. This includes primary reading epilepsy, seizures induced by thinking and eating-induced seizures. For the most part, once the triggers have been identified, exposure can be limited, and that is the typical treatment, along with standard anti-seizure medications