Individual differences in foreign language attrition: a 6-month longitudinal investigation after a study abroad

While recent laboratory studies suggest that the use of competing languages is a driving force in foreign language (FL) attrition (i.e. forgetting), research on "real" attriters has failed to demonstrate such a relationship. We addressed this issue in a large-scale longitudinal study, following German students throughout a study abroad in Spain and their first six months back in Germany. Monthly, percentage-based frequency of use measures enabled a fine-grained description of language use. L3 Spanish forgetting rates were indeed predicted by the quantity and quality of Spanish use, and correlated negatively with L1 German and positively with L2 English letter fluency. Attrition rates were furthermore influenced by prior Spanish proficiency, but not by motivation to maintain Spanish or non-verbal long-term memory capacity. Overall, this study highlights the importance of language use for FL retention and sheds light on the complex interplay between language use and other determinants of attrition.