TexasDude forgot to post this.
Mystery of Permanent Memory Revealed
dailynews.yahoo.com
Wednesday May 16 5:22 PM ET
By Will Boggs, MD
NEW YORK (Reuters Health) - For the first time, scientists have
identified a protein in the brain that is required for turning short-term
memories into permanent ones.
Initial learning takes place in one part of the brain, the hippocampus, but
these first experiences become permanent memories only after
reinforcement in the brain's outermost layer, the cortex, according to Dr.
Alcino J. Silva from the University of California at Los Angeles and
associates.
Until now, little was known about the processes involved in making that
translation.
The authors tested mice that had only half the normal levels of a protein
called alpha-CaMKII. The total absence of this protein results in learning
and memory problems. The model they used enabled the scientists to
separate the short-term learning functions of the hippocampus from the
permanent memory functions of the cortex.
Mice with less alpha-CaMKII learned tasks as well as normal mice, the
authors report in the May 17th issue of Nature, but--unlike normal
mice--they forgot the tasks within a few days. The timing of this memory
loss, they say, matches the shift in the memory function from the
hippocampus to the cortex.
Using sophisticated measurements of the electrical activity of the brain,
the researchers also showed that mice deficient in alpha-CaMKII have
disruptions in the type of activity usually associated with the development
of memories. Again, these disruptions were present in the cortex, but not
in the hippocampus.
``We have uncovered new insights into the function of this protein (it is
involved in the formation of permanent memories in the cortex), but our
work also speaks to the sites and mechanisms required to establish
permanent memories in the brain,'' Silva told Reuters Health. ``This
information will be essential to design therapies to memory disorders.''
``Our article reports the first molecular and cellular information into one of
memory's most mysterious processes: how we establish the memories
that the brain retains, the ones that become our oldest memories,'' Silva
concluded. ``These are very specific (and hopefully important) clues into
this mysterious and wonderful process.''
SOURCE: Nature 2001;411:309-313,248-249. |
