Morphological Family Size effects in L1 and L2 processing: An electrophysiological study

The present study examined Morphological Family Size effects in first and second language processing. Items with a high or low Dutch (L1) Family Size were contrasted in four experiments involving Dutch–English bilinguals. In two experiments, reaction times (RTs) were collected in English (L2) and Dutch (L1) lexical decision tasks; in two other experiments, an L1 and L2 go/no-go lexical decision task were performed while Event-Related Potentials (ERPs) were recorded. Two questions were addressed. First, is the ERP signal sensitive to the morphological productivity of words? Second, does nontarget language activation in L2 processing spread beyond the item itself, to the morphological family of the activated nontarget word? The two behavioural experiments both showed a facilitatory effect of Dutch Family Size, indicating that the morphological family in the L1 is activated regardless of language context. In the two ERP experiments, Family Size effects were found to modulate the N400 component. Less negative waveforms were observed for words with a high L1 Family Size compared to words with a low L1 Family Size in the N400 time window, in both the L1 and L2 task. In addition, these Family Size effects persisted in later time windows. The data are discussed in light of the Morphological Family Resonance Model (MFRM) model of morphological processing and the BIA + model.