A mini-lesson in Spanish vocabulary was taught to undergraduates unfamiliar with the language using one of two predominant L2 teaching methodologies, the grammar-translation approach or the communicative approach. Both experimental groups showed significant improvement in learning the target language over the baseline measure set by the control group, but no significant differences were observed between the two experimental groups. Working memory efficiency appeared to be related to L2 learning. Two weeks later, there were no significant differences between the performance of the any of the groups. A subset of participants who underwent a neuroimaging procedure while performing the experimental tasks showed higher overall cerebral blood flow velocities under the condition based on the grammar-translation approach compared to the condition based on the communicative approach. In the interview component of the present study, participants from the United States and Spanish-speaking countries were questioned about their experience with foreign language education, revealing a significant difference in age at which they learned their first second language and age of second language instruction in their countries. Taken as a whole, these results form a mosaic of the mechanisms and variables involved in second language learning, providing insight into the process of second language acquisition in undergraduate students. Appended are: (1) Informed consent form for main task component; (2) Pre-screening quiz; (3) Demographic survey; (4) Bilingual vocabulary sheet; (5) Graphic vocabulary sheet; (6) Bilingual worksheet; (7) Graphic worksheet; (8) Metacognitive survey; (9) Short-term post assessment; (10) Debriefing form for main task component; (11) Informed consent form for follow-up component; (12) Long-term post assessment; (13) Debriefing form for follow-up component; (14) Informed consent form for neuroimaging component; (15) Debriefing form for neuroimaging component; (16) Informed consent form for multicultural component; (17) Interview questions; and (18) Debriefing form for multicultural component. (Contains 1 footnote, 4 figures, and 1 table.) [BA Thesis, Washington College.]