ABSTRACT
The problem of how a printed word is understood and pronounced has been the focus of an explosion of research in cognitive neuropsychology, experimental psychology, and computational neuroscience since the 1970s. One attraction of this topic is that the task of reading a word can be disrupted by focal brain damage in a variety of recognizable ways that seem to transparently reflect damage to a discrete cognitive mechanism. And yet, many aspects of these impaired patterns of performance can be reproduced by computational models of reading without postulating the discrete cognitive mechanisms that have been proposed to account for impaired performance. Hence, the topic remains rich in controversy and unresolved questions. Nevertheless, there is widespread agreement on the basic computations that are essential to reading aloud and comprehending a printed word. Thus, a schemata of the mental representations and processes underlying reading can help us to understand disordered reading after brain lesions, and can provide a framework for focusing therapy. Furthermore, such a schemata is essential in determining the regions of the brain that are responsible for reading. That is, there is clearly not a single area of the brain that, when damaged, causes inability to read. Rather, a number of areas are likely to carry out separate components of the reading task, so that lesions in various brain regions disrupt the reading process in different ways. Therefore, an account of the components (representations and mechanisms) that underlie reading guides our investigation of the neural substrates that subserve these components.
