This aptitude-treatment interaction study investigated the extent to which explicit and implicit cognitive abilities are differentially related to learning outcomes under two corrective feedback conditions. One hundred and thirteen intermediate English learners of Spanish were randomly assigned to an implicit feedback (recast), explicit feedback (explicit correction), or control group after completing tests from two aptitude batteries (High-Level Language Aptitude Battery [Hi-LAB] and LLAMA). Linguistic improvement on noun-adjective gender agreement and Differential Object Marking was assessed using grammaticality judgment and oral production tasks. Results showed that implicit but not explicit abilities were relevant for the acquisition of gender agreement under implicit feedback as measured by grammaticality judgments. In contrast, explicit but not implicit abilities were relevant for the acquisition of object marking under explicit feedback as measured by oral production. These results lent support to a double dissociation, but they also suggested higher-order interaction effects between the type of cognitive ability, outcome measure, and target structure.