February 2003
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February 2003 |
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He has already demonstrated that "abstract letter identity" - that is, the ability to recognise a letter in whatever form or shape it appears - rather than the shape of a whole word, is one of the major factors assisting the process of word recognition. Coltheart's Federation Fellowship, awarded in 2001, allows him to progress the project. "The key is to get the computer program to process language the way people actually do it," says Coltheart. "One of the new developments we're looking at is enabling the program to spell. At present it can read aloud and recognise words, but not spell," says Coltheart. "The trick about spelling is that if the computational model is going to be able to spell as well as a human can, it must be able to spell words it has never heard before. The challenge is to program the computer to achieve a balance between using the rules, which is essential for spelling a previously unheard word, and not using the rules, which is essential for the many words of English which do not obey the rules. "The other critical thing we're trying to do with the computer model is to understand how people give meaning to a word - no-one yet really understands how this is done." The Fellowship also enables Coltheart to further his work on monothematic delusions - a neuropsychological (rather than a psychiatric) condition caused by damage to part of the brain, in which a patient suffers from one single delusion. Examples are the Capgras Delusion, in which a person believes that someone they are very close to has been replaced by an imposter, and Mirrored-self Misidentification, where a person does not recognise their own mirrored image as themselves. "We believe the explanation of Capgras delusion is that sufferers have two distinct deficits. One is that the link between the system used for recognising faces and the system used for emotional response has been severed, so the patients are not able to respond emotionally to the face of a person who has been a familiar figure in their life. This is what suggests the delusion to them in the first place. "The second deficit is damage to a system used for evaluating beliefs; this system is in the right hemisphere of the brain. This is what prevents them from being able to reject the false belief once it has occurred to them." Coltheart will look at other monothematic delusions - such as the Fregoli Delusion in which patients believe they are being followed by a group of people in disguise, and Cotard Delusion where a person believes themselves to be dead and so do not eat or wash - to establish whether they, too, fit this "two-deficit" theory. Geologist, Dr Simon Turner Ten years ago, when Australia was recognised as one of the leading countries in earth sciences, Dr Simon Turner - a product of the University of Adelaide - decided to look overseas in order to gain experience. But in the ensuing decade, Turner has seen Australia's research reputation fall far behind that of our overseas counterparts.
"Australia has doubly suffered from the funding problems for research. Not only has it not been able to attract overseas researchers and has had to contract within the country, it's also meant that people have been less productive and have travelled less," he says. "Some overseas researchers barely even recognise that research goes on here. If I have any mission it's to try and turn that around." Turner's first overseas posting was at the Open University in Milton Keyes, researching continental flood basalts and uplift of the Tibetan plateau. He later won Royal Society funding to research the use of short-lived isotopes on magmas beneath volcanoes, which he later transferred to Bristol University. He was awarded the prestigious Lyell Award and his Bristol department is now ranked among the best in the UK. Behind it all has been a series of recent theoretical and technological advancements - such as much better understanding of uranium isotopes and new mass spectrometers which can measure them more precisely in smaller amounts of material - that have revolutionised the field. "The exciting thing about using short-life isotopes is that
you can look at very recent events," Turner explains. "Geology
is best known for things like the age of the Earth and the great
antiquity of evolution and very slow processes, but underneath that,
all the things that drive plate motions are things that are occurring
on time scales of days or years. At Macquarie Turner will continue his research on how magmas are generated and passed from the Earth's interior to the surface. As well as gaining a better understanding of the Earth's processes, Turner says his research will undoubtedly also lead to a number of spin-off applications and collaborations. "If you can say something about magma generation and transport, then you can start to talk to people about volcanic eruption prediction and hazard mitigation," he says. "There are also a whole lot of other applications for this isotope system. One is in erosion and river waters, and another is in dating materials such as archaeological remains, homonid teeth, and speliotherms in caves which can then be used to track climate change." Email the researchers: Story by Jane Mundy and Greg Welsh
Disclaimer | Responsibility: Phillipa Janos |
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