Categorical phonotactic knowledge filters second language input, but probabilistic phonotactic knowledge can still be acquired.

Probabilistic phonotactic knowledge facilitates perception, but categorical phonotactic illegality can cause misperceptions, especially of non-native phoneme combinations. If misperceptions induced by first language (L1) knowledge filter second language input, access to second language (L2) probabilistic phonotactics is potentially blocked for L2 acquisition. The facilitatory effects of L2 probabilistic phonotactics and categorical filtering effects of L1 phonotactics were compared and contrasted in a series of cross-modal priming experiments. Dutch native listeners and L1 Spanish and Japanese learners of Dutch had to perform a lexical decision task on Dutch words that started with /sC/ clusters that were of different degrees of probabilistic wellformedness in Dutch but illegal in Spanish and Japanese. Versions of target words with Spanish illegality resolving epenthesis in the clusters primed the Spanish group, showing an L1 filter; a similar effect was not found for the Japanese group. In addition, words with wellformed /sC/ clusters were recognised faster, showing a positive effect on processing of probabilistic wellformedness. However, Spanish learners with higher proficiency were facilitated to a greater extent by wellformed but epenthesised clusters, showing that although probabilistic learning occurs in spite of the L1 filter, the acquired probabilistic knowledge is still affected by L1 categorical knowledge. Categorical phonotactic and probabilistic knowledge are of a different nature and interact in acquisition.