Word morphology has demonstrated to be important in the lexical retrieval of information from memory. In Spanish, word gender is usually obtained adding to the stem the vowel -O for masculine (e.g. niñ-o [boy]) and the vowel -A for feminine (e.g. niñ-a [girl]). In priming studies, when the prime and the target share their stems and vary only in their gender suffix (niña/niño [girl/boy]), event related brain potentials show an attenuation of N400 (Barber, Domínguez & De Vega, 2002; Domínguez, De Vega & Barber, in press).
The present experiment tries to obtain a similar morphological priming effect using word/pseudoword pairs of stimuli. Three conditions were introduced. First, pairs of orthographically related word-pseudoword stimuli (e.g. pato/poto [duck/durk]. Second, pairs including a pseudoword target wit a morphological structure, composed of an existing stem (ran-) and an existing suffix (-o) (e.g. ran-a/ran-o [frog/rano]). This was a very informative condition, because it allows observing morphological effects at a prelexical processing stage. Finally, an unrelated prime-target condition (e.g. mesa/ruco [table/pucla) served as a base-line.
The results showed, the expected N400 attenuation for morphologically related pairs (differing significantly from the base-line condition). By contrast orthographically related word-pseudoword pairs did not show any significant effect. These differences support a prelexical, morphological (not merely orthographic) interpretation of the overlapping in the critical condition rana/rano.
References
Barber, H., Domínguez, A., & De Vega, M. (2002). Human brain potentials indicate morphological decomposition in visual word recognition. Neuroscience Letters, 318, 149-152.
Domínguez, A., De Vega, M., & Barber, H. (in press). Event Related Brain Potentials elicited by morphological, homographic, orthographic and semantic priming. Journal of Cognitive Neuroscience, 16(4).