Using plasticity-related changes after brain damage to reveal the nature of the neurocognitive systems underlying language: evidence from neural networks and neuropsychology and functional neuroimaging of reading

Abstract

The way in which the brain supports language is a major question in neuroscience. Language is central to our everyday activities, pursuits and professions and when language is affected by brain damage, serious disability results. The traditional approach to understanding how the brain supports language has entailed studying each type of language activity (e.g., reading, speaking, repeating, etc.) in relative isolation and, from this, specifying the underlying processes for each. In our recent work we have tried to take a different approach. Our working hypothesis is that the brain supports a small number of “primary” systems – the meaning of words and concepts (semantic memory), the sounds of words (phonology), and vision (which is used for recognition of written words as well as other visual objects). These three primary systems work together in order to support a whole range of language activities. This means that in order to understand how the brain supports language, we need to work out how each system learns to process the information required for each language activity and how the connections between each system are adjusted until the correct balance is achieved.

This project will use two neuroscience methods to provide converging evidence to answer these key questions: computational models (mathematical models that mimic the processing that occurs in the brain) and behavioural investigations of patients (neuropsychology). The nature of each of the primary systems and their interconnections is perhaps most apparent when the global system is changing in response to environmental pressures. We will, therefore, study the changing system during recovery after damage using the two different neuroscience methods. The study of computational models and patients during recovery after damage has been overlooked by previous research in this area. By developing these methods we will allow future neuroscience studies to glean a novel and powerful source of information about the neural basis of language.

Duration of the project

August 2006 - Dec 2010

Funding body

• Gatsby Charitable Foundation