Lasting nature of both transfer and interference in amygdaloid kindling in cats: observation upon stimulation with 11-month rest following primary site kindling.

Eleven months after the completion of primary site amygdaloid (AM) kindling, three cats experienced kindling of the secondary site AM. At the secondary site, animals developed kindled seizure with a mean of eight stimulations, which was significantly fewer than the 29 required at the primary site, indicating a presence of a positive transfer effect. However, the ictal architecture of the secondary site-kindled seizure was significantly different from that of the primary site: in the former, there was a marked delay in secondary generalization, with individual kindled seizure having a significantly prolonged seizure duration. Both the transhemispheric positive and negative transfer effects observed with the secondary site AM kindling reflect the lasting nature of the neural remodeling induced by the primary site AM kindling. This finding may have clinical relevance.