Local Synaptic Changes During LTM

Professor Eric Kandel discusses changes in synapse structure during long-term memory. Research indicates these changes are synapse-specific and not neuron-wide.

An interesting question that has emerged in the study of long-term memory is, since long-term memory involves genes and therefore the nucleus (an organelle, which is, in principle, in contact with every synapse of a neuron), does that mean a neuron must change every one of its several thousand synaptic connections in a long-term process, or, can one in the long term, restrict certain connections, alter their strengths, and not others? This is fundamental because if every long-term process is neuron-wide, the ability to store information in the brain is dramatically restricted. But if a neuron can store different kinds of information at different terminals, you obviously expand the information power of a nerve cell dramatically. All the recent studies of the last three or four years have shown that you can have long-term changes that are synapse-specific. So, you retain the informational power of the individual neuron.