Marín, J. 1 , Pérez, M. A. 1 , Pagán, A. 2 , Stadthagen, H. 3 & Izura, C. 4
1 University of Murcia. Murcia. Spain
2 Laboratoire CeRCA, Université de Poitiers - CNRS, France
3 ESRC Centre, University of Bangor, Bangor, UK
4 Swansea University, Swansea, UK
Words that are acquired earlier are processed quicker o more accurately than words that are acquired later (Carroll & White, 1973). This Age of Acquisition (AoA) effect has been the topic of various debates about its independence of frequency effect, and its locus, nature, and singularity. There are also metrical and methodological problems to precise the time at what a word is acquired and the isolation of AoA effect from the effect of other factors with it is highly correlated.
Isolation of effects usually requires laboratory control techniques but this stratagem faces the problem that the natural learning process (which requires massive and long periods of practice) is not properly reflected. On the other hand, correlational designs can afford the natural phenomenon but here we have the inconvenient of multiple colinearity.
We present a new approach in which we approximate the typical controls of experimental design but keeping the word learning process as it happens in normal life. First, we have developed a corpus with all words in the texts that students of psychology use to prepare the subjects and exams. With this corpus (PsyLex) we have selected words that have a frequency in Lexesp lower than 0.72 per million, but that have a high/moderate PsyLex frequency. The list of selected words has been further selected to obtain three lists of 24 words that don't differ in Lexesp frequency, length, PsyLex frequency and N. Each list has words that appear mainly in the first, second or third course. These words have been used to generate a paired list of pseudowords by changing two letters. With this material we tested 4th grade psychology students with a lexical decision task. Obtained results confirm the order of acquisition effect observed in previous research.