Also known as seizure-induced synaesthesia. Both terms are used to denote a type of "synaesthesia (i.e. a member of the group of perceptual phenomena exemplified by "colour hearing) which falls into the class of "non-idiopathic synaesthesias. Pathophysiologically, epileptic synaesthesia is associated primarily with partial epileptic seizures affecting the limbic system or temporal lobe. As such, epileptic synaesthesia is also classified as an experiential phenomenon.
References
Cytowic, R.E. (2002). Synesthesia. A union ofthe senses. Second edition. Cambridge, MA: MIT Press.
Dictionary of Hallucinations. J.D. Blom. 2010.