Researchers at New York University have uncovered vital new clues as to why many people with epilepsy experience memory problems.BackgroundThe formation of memories requires extremely precise co-ordination of activity between the brain cortex (the brain’s folded surface) and the hippocampus (found deep within the temporal lobes). Previous studies have shown that spontaneous bursts (SBs) of epileptic activity in the brain in between seizures can impair memory, but the underlying mechanisms for this have not been fully established.Study and findingsIn a recent study, the team in New York investigated the interaction between the cortex and hippocampus, and its link to memory impairment, in rodent models of epilepsy. They discovered that SBs arising from the hippocampus were closely linked to specific changes in activity in the cortex and the hippocampus, and to a subsequent disruption in communication between the two, both during different stages of sleep and during wakefulness. In turn the presence of these ‘altered’ patterns of activity correlated with impaired memory consolidation in the animals (on standard testing).The researchers went on to examine four people with focal epilepsy, and found a very similar association between SBs and altered patterns of communication between the cortex and hippocampus.Further research is needed, but these findings, published in the journal Nature Medicine, suggest that SBs may alter the normal interactions between the cortex and hippocampus, and disrupt the process of memory consolidation, leading to memory problems.Significance This study is very important, because it has potentially linked specific patterns of activity in the cortex and hippocampus to memory impairment, and it has shown that these patterns are likely to be the result of SBs. This knowledge could, in the future, lead to interventions that prevent these changes from happening in response to SBs, protect the ‘normal’ patterns of communication between the cortex and hippocampus, and preserve the process of memory consolidation.  If successful, this would have enormous benefits upon the lives of people with epilepsy.Click here for more articles about conditions related to epilepsy.