It doesn't have to be stress to erase the short term memory. Almost
anything, verbal or visual distractions, can erase this memory. In a class
for Check Airmen, we have a module on the checklist and why it is SO
important. One task of the checklist is a memory aid. I ask, "How many of
you have been headed in to a room and on the way, your spouse stops you and
asks a question. You answer it and continue on your way only to wind up in
the room asking yourself, 'why was I coming in here???'". Everyone has done
this and it is a vivid example of how short term working memory vanishes.