Binding and Inference

We know that color and form are processed in distinct areas of the human brain. This information must somehow be brought together. How the brain might achieve these colorform associations, as well as all other associations of this type, is one of the central themes of this dissertation. When looking at a field of poppies on a sunny day, how can we correctly associate the color red with the poppies, green with the grass, and blue with the sky, while avoiding associating the color red with the grass and the color blue with poppies? How can we associate the perception of red poppies with the name “red poppy,” and with its superordinate category “flower?” A red poppy is composed of several features, like its shape, color, texture, etc. How might a cognitive system bind these features to build a coherent whole? If we see Louise picking a red poppy, how can we correctly associate Louise with the picker and the red poppy with the picked object, without making the opposite and incorrect association? These associations may seem easy to us, but how does the brain achieve them? How a cognitive system binds a set of features together, associates a filler with a role, a value with a variable, an attribute with a concept, ... is what we mean by “the binding problem.” This thesis focuses on the neurobiological processes that enable connectionist cognitive systems to display binding abilities, on the constraints that affect the binding process, and on the cognitive consequences of these constraints. To study these processes, we developed a computer model of them. This method forces a detailed and unequivocal description of processes used by the simulation. This method is also a powerful means of generating new hypotheses. In this study we attempt to link psychological processes with the neuronal constraints that act on brain functioning. The brain is composed of approximately 10 billion highly interconnected neurons. To achieve binding it is necessary for neurons to communicate with each other because it has been shown that different aspects of a perceived object are not processed in the same cortical areas. Therefore, there must be a means for binding neurons responding to each of these different aspects. The neurons responding to