Recent studies in the second language acquisition of negation have focused on polarity items and their licensing contexts. Although several studies show a correlation between higher degrees of second language (L2) proficiency and the acquisition of the target L2 structures, less attention has been given to the relation between the acquisition of polarity sensitivity and different types of lexical polarity items. This study addresses this gap in the literature by measuring the processing of polarity-sensitive items under the scope of negation in L2 Spanish. Our findings indicate that learners' acquisition of polarity sensitivity differs across different types of lexical polarity items.