The problem: visual memory

Our research is focused on determining the neural correlates of visual memory in the context of well-defined tasks that have parallels in humans and animals. We are inspired to do this work, in part, to lay the groundwork required to understand memory to the degree that we can treat memory dysfunction. Another thing that inspires our work is the remarkable visual memory capabilities of humans, which have been documented in a number of ways.

Massive capacity, single-trial memory for pictures - We store memories of the objects and scenes that we have encountered after viewing thousands, each only once and for a few seconds. Early illustrations of this include a classic 1973 paper by Lionel Standing, "Learning 10,000 pictures". More contemporary work by Aude Oliva's group at MIT has determined that these memories are stored with considerable visual specificity. This type of memory is often probed with the the question, "Have you seen this before?" and it is commonly called "recognition memory". Our recent work (e.g. here and here) has focused on understanding how the brain supports massive capacity, single trial learning.

Image memorability - It turns out that all images are not equally memorable, but instead we find some images easier to remember than others. Intriguingly, these memorability differences are not primarily driven by individual differences, but rather, we all tend to find the same images memorable and forgettable. While the answer to the question "What makes an image memorable?" is complex, computer algorithms are very good at predicting how memorable images will be and some can even enhance the memorability of images. Our recent work and has focused on understanding how memorability variation is reflected in the brain as well as models of visual processing.

The "Memory Palace", also called the "Method of Loci" - This memory technique was employed by the Greeks and Romans and it continues to be used in memory competitions today. The technique involves enhancing our ability to remember things we are typically bad at (such as strings of numbers) by mapping them onto something we are really good at - remembering pictures! Joshua Foer's "Moonwalking with Einstein" is a wonderful account of both the history of the technique as well as his personal experience with it.

Our everyday experience - We have all had the experience of walking down the street, encountering someone, and remembering that we know them but not being able to recall any other details (at least for a few moments). This experience illustrates the distinction between the percept of "familiarity" and the "recollection" of facts, and considerable evidence suggests that these percepts do in fact map onto different memory systems in the brain. We also experience the percept of familiarity during déjà vu, but in that case we have the eerie, conflicting feeling that something is both familiar to us and that cannot be true.