It often happens that, when we move from one place to another, we forget what we were going to do .

This often happens when we trace routes to which we are already accustomed: going to work, to school, etc. We realize, then, that we have subconsciously taken the route to our office when in fact we want to go visit a friend, just because both routes share the initial stretch and we are more used to going to work than to visiting the colleague’s apartment.

Thinking about doors

This is because, having gone through the same place so many times, our brain codes this route as the default way to go, hits the “autopilot” button and, while our feet are quietly taking us down the wrong path, we can devote ourselves to thinking of other, more interesting things. However, at other times we forget completely what we were going to do when we are in our own house , a place we frequent so much that there is no “default route”.

In these cases, the only thing that remains in our consciousness is a feeling of having had a very clear objective seconds ago, a purpose that no longer exists except as an inexplicable disorientation. Furthermore, as a consequence of this daze, we find it difficult to mentally recapitulate the actions we have carried out just before finding ourselves where we are, and perhaps for this reason, we do not realize that the last thing we have done before our destiny disappeared from our mind is… to pass through a door.

Cut sequences

Surprisingly, the key to these little everyday mysteries could be right there, in the doors . There are indications that passing through one influences our memories unconsciously and that, in reality, the simple fact of imagining that we passed through a door can cause these memory erasures (Radvansky et al, 2011) (Lawrence & Peterson, 2014). That is, that thinking about doors can make it easier for us to forget the thread of what we were doing . The explanation is problematic, but could be the following: doors act as dividers of our memories.

Perhaps as a matter of performance, our brain splits our flow of experience into smaller portions. In that sense, the mental representation of a door would act as a trigger for one of these divisions exerted on our mind, cutting unconsciously the “narration” of the facts that we are living. We can think of these fragments as the film shots that divide any given film. Fortuitously, important aspects when developing a plan of action can get lost in this “cutting” process and not move on to the next fragment: that is why we often get up from the sofa and end up paralyzed by uncertainty a few meters further on.

Does it only happen when you think of doors?

However, by this same logic there are other elements that can have the same effect on us. For example, we have observed how phrases that introduce a temporal discontinuity produce the same effect . Thus, when we read something like “a week later…”, our capacity to associate memories is less for those memories that are on either side of that time division if we compare them with memories that are in a single fragment (Ezzyat et al, 2010).

It is also because of this mechanism of division that it is so easy to have the need to reread the last lines after realizing that the narrative we are reading has taken a leap in time or space (and is therefore different from the last one we remember). It is not the book’s fault, nor does it have to be because what we are reading lacks interest. It is the memory assembly system operating in our brain that is responsible for these things happening.

The latter is interesting because it highlights the symbolic nature of this process. It is not that we are biologically predisposed to forget when thinking about doors, it is that this is a side effect of the symbolic charge of these artifacts . This means that practically any other perceptive phenomenon can produce in us the same effect if we subconsciously assign a similar meaning to the one doors usually have. Do you hear that? It’s the psychoanalysts, who are already sharpening their pencils.