One of Netlab's synapse
mechanisms and structures is based loosely on a silent-synapse hypothesis of long- vs short-term memory, in which short and long both occur at the same connection-point (synapse). Netlab includes a learning method
based on this as well, called weight-to-weight learning
. The silent synapse phenomenon has been observed for quite some time in biological studies, and there has been very good evidence to explain some of the underlying mechanisms responsible for the observation. Still there have been many missing pieces to the puzzle.
Recently there has been a development that seems to give evidence and details to a related theory/hypothesis of how synapse strength may be mediated through a molecular motor called Myosin II on the post-synaptic
side. So suggests one study out of The Scripps Research Institute
It has been thought for some time now (see background information below) that molecular motors resembling those used to produce movement in muscle tissue, may be a major player in the processes mediating the transfer of memory-connections from short-, to long-term on the post-synaptic side. We now seem to be getting to more detailed understanding of the mechanisms underlying these phenomena. Like so many brain constructs, there does seem be a great deal of variety.
The vernacular that seems to be emerging is that these mechanisms "stabilize" the connection strengths. This might still be jumping the gun on the conclusions, but it is not a bad way to think about it for now.