WHEN YOU read these words or recognise someone's face, some of the same parts of the brain are involved. Psychologists in the UK are investigating this with the aim of trying to understand and even help those with reading problems caused by dyslexia.
Prof Padraic Monaghan of the University of Lancaster, speaking at the BA Festival of Science in Liverpool, explained how neuroimaging studies have revealed that the brain processes visual images of faces in an area of the right hemisphere known as the "occipitotemporal cortex" (OTC), while visual words are processed in a corresponding area in the left hemisphere. "We know from the structure of the brain that . . . this visual word form area and this face processing area are directly connected via a set of neural fibres in the middle of the brain called the corpus callosum," explained Prof Monaghan.
As well as this structural similarity, there is also "activation overlap" when processing faces and words. For example, Prof Monaghan cited a 2003 study which showed that both the left and right OTC became active when dyslexic adults viewed faces.
While most people know of the developmental reading problem dyslexia, not many know of a problem affecting the ability to recognise faces. Known as "developmental prosopagnosia", the prevalence of this disorder is unknown. This is "typically because people don't recognise they have it".
Prof Monaghan and colleagues aim to gain a clearer understanding of the complexity of both developmental dyslexia and developmental prosopagnosia by using techniques including behavioural studies, the creation of computational models and brain imaging.
Prosopagnosia may not greatly impair someone's day-to-day life, but dyslexia can have major educational and vocational consequences.