 Hi, and welcome back to this biological psychology video course. In this section, section 4, we're going to talk about memory. Now, this is section 4.1, the introduction to section 4, so we're going to start with some reading and as for the other sections of this video course, we're going to use the free textbooks from OpenStacks, which you can download from OpenStacks.org. And in this case, we're going to use from the psychology textbook chapter 8 on memory. Now, I always like to recommend also a more accessible textbook for the interested viewer. And in this case, I would like to recommend the book Thinking Fast and Slow by Daniel Kahneman, this book. I don't have to cover, but normally it looks as you see here on the screen. Daniel Kahneman is the only, so far, the only psychologist ever to win a Nobel Prize. He won it in the field of economics, actually, because there is no Nobel Prize for psychology, but his work on essentially human factors in economics has won him a Nobel Prize. And in this book, he talks about the distinction between system one and system two, as he describes it. So this distinction between, on the one hand, the way that we make decisions based on our gut feelings, sort of without actually consciously thinking about our decisions. And on the other hand, are the way that we sometimes in other situations make decisions based on conscious introspection. So when sort of our analytical thinking, right, these according to him, these are different systems. They are, I think, different systems to some extent. So this is really a good book, well written. He's a very, he's a great scientist, really. I should say that it is partly outdated because some of the chapters rely on studies from social psychology, mostly, that have during the so-called replication crisis in psychology, been shown to be non reproducible, to be essentially not real, right? So take a few, that is a shame. And I kind of feel bad for Daniel Kahneman, that his great book suffers from this, from this, from this replication crisis. But keep that in mind while you, when you're reading, thinking fast and slow, that not all of the findings that he describes are probably true. But as a whole, I think the book is still very much worth reading. Now, so what are we going to take a look at in this section? In video 4.2, we're going to take a very brief look at what memory is. And in 4.3, we're going to take a look at sensory memory, sort of the most basic form of memory that we have. Sort of a trace that, that perceptual impressions leave in our brain. Then we're going to take a look at working memory, sort of the type of memory that you use, for example, when you're keeping a phone number in mind, right? When someone tells you a phone number and you sort of keep that, you're rehearsing that in your working memory to not forget it. Now we're going to take a look at working memory. So we're working memories, essentially every form of memory that lasts for a very long time and does not require active rehearsal. And finally, we're going to take a look at a very fascinating subject, namely the reliability of memory. And we're going to take a look at the various ways in which memory can be distorted or lost. Now with that, let's move on to video 4.2, in which we're going to take a look at what memory is.