This dissertation executed a novel rare word learning paradigm to investigate whether learning words via different modalities (ie, auditory vs. visual) influences subsequent word knowledge. The study was split across two days. On day one, adult participants learned the definitions or pronunciations of 90 rare words via different modalities. On day two, participants read these 90 learned words in semantically congruent and semantically incongruent contexts, while behavioral and neural measures of word knowledge were collected. Additional factors that were expected to influence the relationship between word learning modality and subsequent word knowledge, like reading comprehension ability, phonological decoding skills, phonological recoding skills, and orthographic transparency, were examined. Behavioral results indicated word learning modality influenced word identification accuracy and orthographic transparency influenced word identification speed. Further, the interaction between phonological recoding skills and word learning modality impacted word identification speed. Preliminary ERP results are discussed. This dissertation provides information on how word learning modality as well as person and word characteristics impact vocabulary learning and subsequent word processing during sentence reading.