The locus of frequency effects in word recognition

One of the major tasks facing cognitive psychologists is to understand how humans recognise words. Models of word recognition are influenced heavily by experimental research, and one of the most robust findings is that frequently used words (eg "house") are recognised faster than rare words (eg "larch"). However there is debate over the exact nature of this 'frequency effect', particularly whether it reflects the earliest stages of word perception. Related to this issue is the question of whether word recognition competes for attention with other tasks (eg driving a car). Many theories assume that word recognition can occur automatically, and therefore it should not matter if we are engaged on another task. However, recent research has suggested this may not be the case and that word recognition does require attention.
This project uses a "dual-task" method where participants perform two tasks in quick succession, one of which involves word recognition. Through manipulation of the frequency of the words involved, the technique will be used to demonstrate the role of frequency at different stages of word recognition and the degree to which word processing places demands on attention. The results will have implications for the development of models of word recognition.