Posted on 27 August 2003
Dr Gaskell's research demonstrates how people's ability to process familiar words is slowed down when they learn new words that are similar. So, crossword addicts beware, learning all those words could actually make you slower at understanding speech!
The research trial has focused particularly upon learning new spoken words. This is because reading is an acquired skill, whilst learning spoken words is a basic human instinct, and is the way in which children first acquire words. This ability to learn new words is a skill we seem to have for our whole lives.
Participants in Gareth's study (carried out with Nicolas Dumay at York) were introduced to a range of novel non-words based upon a familiar word. These words shared a beginning, for example, ‘cathedral' and the non-words ‘cathedruke' and ‘cathedruce'. The participants were exposed to the non-words to see if learning them affected the time it took for them to recognise the familiar word.
The results of the study showed that when exposed to the new words for a short period of time (half an hour), the ability to recognise familiar words was not affected. However, over the course of a week, the speed at which familiar words were recognised was slowed because the new words had begun to compete with them in the brain. This effect was only seen with words that had similar beginnings, not with words that diverged from the start, for example, ‘yothedral' and ‘cathedral'.
"It would seem that there are two different areas of the brain that are involved in word recognition," said Dr Gaskell. "In the short term a word which is encountered a number of times is held in a part of the memory in which it does not compete with other, already familiar, words. A few days later, however, the word becomes located in the mental lexicon where it competes with other words. This mental lexicon is, in effect, like a large database. The more items it contains, the longer it takes for a precise word to be found. But thankfully for our participants, the recognition delays induced by these experiments are small – little more than a fiftieth of a second."
"This research helps us to understand the way in which people process and learn spoken language, and may help us find better ways to learn words. In collaboration with colleagues in the department, we have begun to look at how dyslexia affects word learning, and the findings may also be applicable to areas like language development and recovery from brain damage."