SKILLED PERFORMANCE, PRACTICE, AND THE DIFFERENTIATION OF SPEED-UP FROM AUTOMATIZATION EFFECTS - EVIDENCE FROM 2ND-LANGUAGE WORD RECOGNITION

Practice on cognitive tasks, in general, and word recognition tasks, in particular, will usually lead to faster and more stable responding. We present an analysis of the relationship between observed reductions in performance latency and latency variability with respect to whether processing has merely become faster across the board or whether a qualitative change, such as automatization, has taken place. The coefficient of variability (CV) - the standard deviation of response time divided by the mean latency - is shown to be useful for this purpose. A cognitive interpretation of the CV is given that relates it to issues of skill development. Data from second language learners' word recognition performance and from a simple detection task are presented which confirm predictions drawn from this interpretation of the cognitive significance of the CV. Initial improvement in a second language word recognition task was interpreted as involving more efficient controlled processing, which later gave way to automatization. The implications of this index of skill are discussed in relation to second language development and the general issue of automaticity of processing components in cognitive skills.