Processing of Spanish Preterite regular and irregular verbs: the role of neighborhood density

Research into lexical processes shows that frequency and phonological similarity (neighborhood density) affect word processing and retrieval. Previous studies on inflectional morphology have examined the influence of frequency of occurrence in speech production on the inflectional verb paradigm in English. Limited work has been done to examine the influence of phonological similarity in languages with a more complex morphological system than English. The present study examined the influence of neighborhood density on the processing of Spanish Preterite regular and irregular verbs as produced by thirty native speakers of Spanish. The results of a naming task showed that regular verbs were processed faster and more accurately than irregular ones. Similar to what has been observed in English, a facilitative effect of neighborhood density for -ir verbs was observed in both regular and irregular verbs, such that -ir verbs with dense neighborhoods were produced faster and more accurately than -ir verbs with sparse neighborhoods. However, no neighborhood density effects were observed for -ar verbs (regular and irregular) in reaction times and accuracy rates. Thus, the activation of a specific -ir verb was facilitated by similar sounding verbs regardless of being regular and irregular. Implications for models of morphology language processing are discussed.