Scientists at Edinburgh University have identified the role played by a protein - called BDNF - and say the discovery could lead to the development of new drugs.
They analysed the way cells communicate when the brain is most active, such as in the seizures.
They found the BDNF molecule has the harmful effect of blocking a process known as activity-dependent bulk endocytosis (ABDE). By doing this during a seizure, BDNF increases the release of neurotransmitters and causes heightened electrical activity in the brain.
Since ADBE is only triggered during high brain activity, drugs designed to target this process could have fewer side effects.
The researchers, however, warned that since ABDE is also implicated in a range of brain functions, more research is needed to establish what the effects of manipulating this molecule might be on these processes.