ABSTRACT
Acquiring a second language (L2) as an adult is arguably a challenging and complex task, often resulting in a high degree of variability in learning trajectories and outcomes. In the last 20 years, there has been a significant increase in experimental studies examining L2 neurocognition using a wide range of neurocognitive methods, many of which have provided critical insight on the individual difference factors that underlie L2 acquisition and processing. This research has explored how individuals differ from one another in terms of their background characteristics and cognitive capabilities, as well as the linguistic, instructional, and contextual factors that modulate L2 outcomes and general performance. The goal of this chapter is to review empirical evidence that aims to explain, at least in part, the underlying factors behind L2 neurocognition as well as the individual variability often found in learning trajectories and outcomes in adult L2 acquisition.
