Please put a door between them

[Added November 2011]
The method of loci so well described by the book Moonwalking with Einstein
by Joshua Foer is based on remembering hundreds of loci . There are rules on
how to create them in such a way that they can be easily remembered. These include
the fact that they should have all about the same size, be well illuminated , well separated, … These rules are obvious since they make more easy the
recollection. New research by Radvansky and others
make more clear what means “well separated” and how it works. I couldn’t get
the original paper but a previous paper on the same subject:
Walking through doorways causes forgetting:Situation models and experienced space describes very well the experimental protocol. The experiments are done using computers and virtual reality techniques: you are requested to walk a space
containing many desks with objects on them. You carry an empty box and you
should pick an object and put it in the box. Than you carry it to another
desk. This will go on for some time and different objects. From time to time
you are asked what you have in the box. It is as simple as this. You have
to remember only what is the last object that you picked. Here the interesting
result is the following : if you use the same space and the same desks layout
but put one or more walls and doors between them, the number of times you
forget the object’s name increases. In the last paper Radvansky has demonstrated
that there is real forgetting because the person doing the experiment will
return after passing a few doors in the place where he picked the object and
there is no recovery of memory:i.e. the fact of passing a doorway will produce
a permanent forgetting. Radvansky explains this “the act of passing through a doorway serves as a way the mind files away memories”.

From this research it is also apparent another striking feature of our brain: it works in the same way in real world, in virtual reality, reading
about a scene, looking at the scene in a movie and of course imagining
the scene as they do in the method of loci. This may seem surprising but it
isn’t if you just replace our brain with a computer trying to move in
real world. Of course the computer doesn’t interact with real objects but only
with a stream of 2D images and other data. Using these it must create a 3D
model of the unknown real world. It is exactly what the brain does but it
does it so effortlessly that we may think that we are interacting with real
objects. This instantaneous simulation of reality is also done by our brain
when it reads a text , sees a movie or imagines a walk in a memory palace.

Now coming back to the method of loci. The essence of the method is that you
store all the information you want to remember in the loci of the memory palace.
Then you get this information back walking from locus to locus. As you do this,
it is important also, that, after you extract the information from a locus
(something like picking an object from a desk), this information shouldn’t bother you any more (since you have already used it) and so, to forget it, you
just imagine that you pass a doorway and you arrive at the next locus ready
to pick a new object.

Instead in real life you may want exactly the opposite when you have forgotten what you needed from the refrigerator. Before passing the doorway
use for example some hand gesture to remember and reverse the door’s effect
on memory. Or just keep repeating the name of the thing you need…

In which conditions you remember best

[Added December 1998]
I try to recall from time to time long lists of items learned with the
method of loci. I have got some experience on the best
conditions to remember things.

  • During walks in a peaceful, natural setting.
  • In bed after the night sleep, when you feel relaxed but no longer
    fall asleep.

  • Always in bed when you are not very tired by hearing a special relaxing
    sound produced by computer.I use the program Cool Edit of Syntrillium to produce the stereo
    waveform that I listen through stereo headphones. You can find the details in the manual.

Move your hands to remember!

[Added December 1998]
Why do we gesture when we speak? To this question Robert Krauss has,after a long research, the following surprising answer. The main purpose of hand gestures is not to communicate but to facilitate access to the mental lexicon.Krauss tells a story about this:
two friends walk together in a icy cold day. One of the two speaks and speaks moving the hands;the other remains silent with his hands kept in the pockets.
“Why are you so silent today?” asks him the always talking friend.”I forgot to take the gloves with me”, answers the silent one.

Perfect recall and perfect oblivion are impossible

[Added May 1997]I have “experimented” for many years
with learning and recollecting long lists of words (around 1000 items).
What you discover with this exercise,that apart from the initial effort
to learn the list,once you know it by heart,you have to rehearse it
regularly to keep it in memory. In my case I found that I had to rehearse
every month, otherwise the list would start to lose its pieces.
The “damage” was proportional to the time passed without recollection:after
for example, one year, re-learning the list was a big job, although not like
the first time. Until now, I have found no way to ensure a perfect recall
of a list without periodic recollections. On the other end ,it is also
true that a list never goes really away. For example,around 20 years ago,
I learned by heart a list of 1000 movies titles but I didn’t rehearse it
any more, after the initial learning. Now , when I see the title of
a movie, I can easily remember that it was in the list.

Sometime it would be nice to have something like perfect oblivion.
Think about all those sad memories haunting you from the past. Unfortunately
this proves impossible because of the way our memory system works.
Not only are our memories scattered everywhere in the brain, but part of them are
outside the control of our consciousness. In fact our brain seems to have
two systems that work in parallel,each one with its memory:the unconscious
one is based on the inner brain and ensures a quick reaction to dangerous
situations. The other one is under our consciousness and will examine
later the situation. So if we see something looking like a snake on our way,
we first jump to avoid it and then we look more carefully to discover that
it is only a stick. It is possible that the memories used by the inner
brain are impossible to erase.