How Memory Works

in classical ideas about how the memory records memories of events for example there's the idea that the brain processes a sequence of signals and the signals come from the perceptual regions of the brain and they sort of go in one direction to higher and higher order regions of the brain like for example the anterior temporal lobe or the anterior frontal lobe and it is there at that point that the both the most complex perceptions of complex events as well as the most complex memories of complex events are formed so the idea is that if you are listening to somebody singing or talking and at the same time seeing the person and sort of feeling yourself sitting in a chair because you are in a concert hall that those separate impressions are only going to come together in very high order regions of the brain and that's where they they are going to be perceived so that's where you have your sort of film experience with soundtrack and whatnot and that's also where the recording is going to be made and there a lot of reasons why this cannot work this way and about 20 years ago we were dealing with this problem and then we proposed the framework in which we said well first of all we now are beginning to know that everything that moves forward in terms of signaling in the brain does not move just in a forward direction but as it moves forward there's also a feedback loop that comes to the origin of the feed-forward so basically we're dealing with loops that advance but also can come back on their tracks to the original point there was something there was begin to be known in that was very interesting because it opened up possibilities about the circuitry so this is not just in one direction but in multiple directions that include both the forward and the backward and the other thing is that there was clear evidence that when you lose as a result of damage to the brain when you lose regions of the brain that are very high up like an anterior temporal lobe or interior frontal lobe lo and behold you don't lose the possibility of having a complex perception of the world in other words your filmic experience still remains nor do you lose the possibility of remembering a complex perception in fact the only thing you lose is the possibility of dating and recognizing the uniqueness of the perception so that discrepancy led us to propose this idea that there was a system of convergence that went over multiple hierarchies towards certain anchor points in the brain in that what the convergence was achieving with leading signals to a certain point the convergence divergence zone and what was being recorded there was not all that was happening in your filmmaking experience but rather the fact that something had happened back here that had happened simultaneously in this region in this region in this region and then by dint of the feedback the the the the the backward projection we would have the possibility later on of reactivating the entire experience now what this is she and that's that the notion of convergence divergence so I actually at first I only called it convergence and I remember Francis Crick telling me don't call it just convergence that's what people are going to remember they will never think about the divergence part and then I later corrected this because it was quite right and so the idea is that when you are asked to remember a certain experience that you have today in which you're talking with person a listening to the person's voice but you also are in a certain context B which is the context of a certain room in a certain building you're going to have the separate recordings of the of the voice of the person the sight of the person the place but those recordings are going to be reactivated only if another recording of the simultaneity of the event has been made in a convergence diversions so and so you you send signals forward through convergence and then divergence will allow for what I call the process of retro activation in the retro activation is going to take place in different sites at the same time approximately or in rapid sequence at those different places like for example when we when we replay music in our minds and so what this does just to finalize the story is create a solve a great problem of economy in other words in instead of having to record every event that you're going through in your life every day with every kind of person with the books you read the things you see and hear in touch and smell what you need to do is record conjunctions of the occurrence of certain events and then out of the conjunction you can replay you can reconstruct and so memory in this perspective is always reconstructive you are always trying to get at some approximation of what went on rather than an exact recording of what went on and that's where the big difference between the the recording in terms of the photograph or in terms of celluloid the picture comes we are not like that we don't have these they are all of this celluloid or polaroid pictures filed in some place and we don't just replay them in a screening room we have something that is both far far more complex but at the same time far more economic and that also to certain extent because of its fragmented nature far more prone to error all of these things come into the picture

Channel: Big Think

Views: 74,132

Keywords: bigthink, Big Think, BigThink, BigThink.com

Id: kwo2WxM87-g

Length: 7min 16sec (436 seconds)

Published: Fri Jun 10 2011