Researchers at a trio of universities have found that reactivating a specific memory does not affect associated or related memories, adding to our understanding of how memories are stored and influenced. The study appears in the latest issue of the Proceedings of the National Academy of Sciences.
The study's authors are Jacek Debiec and Joseph LeDoux of New York University's Center for Neural Science, Valirie Doyhre of NYU and Universiti Paris-Sud, and Karim Nader, a psychology professor at McGill University.
Memories are made in stages. These initial stages involve learning followed by consolidation--a process during which the memory trace is formed. Unconsolidated memories are susceptible to disruption. Therefore, various pharmacological agents or interfering tasks applied before consolidation occurs prevent a memory from persisting. However, once consolidation occurs, memories may be long lasting--one experience may create memories that last a lifetime.
For years it had been believed that consolidated memories were resistant to drug manipulations, which are effective in the early stages of memory formation. However, increasing number of data indicate that reactivation of consolidated memories renders them susceptible to treatments, which may result in either impairment or enhancement of the reactivated memory. This process is often referred to as reconsolidation, which has been proposed as a possible way of treating traumatic memories. Yet, several concerns have been raised that reactivating and disrupting a single memory may also affect other associated memories. Debiec and colleagues found that only directly but not associatively reactivated memories are vulnerable to disruption.