Vagus nerve stimulation (VNS) has been used to address the symptoms of treatment-resistant depression (Rush et al., 2000) and is proposed to also alleviate anxiety effects (George et al., 2008). Transcutaneous VNS (tVNS) offers a less invasive treatment mechanism for clinical populations; however, little is known about tVNS effects on mood and anxiety in a non- clinical adult population. Using auricular tVNS, the present study showed that 10 minutes of tVNS immediately preceding second-language learning across three consecutive days reduced state negative affect, somatic anxiety, and cognitive anxiety, dependent on task performance and/or trait mood/anxiety.

The acquisition of the grammar of a second language requires a variety of cognitive mechanisms, including inductive reasoning. In the current study, we examine the cognitive underpinnings of grammar learning with an explicit-inductive (rule search) learning task, designed to capture more of the complexity associated with grammar learning than purely deductive tasks. Research in language aptitude has shown that working memory capacity (WMC) is a key predictor of grammar learning outcomes. Inductive reasoning and grammatical sensitivity are other established aptitude factors. The goal of the present study was to determine the degree to which relevant variables predict learning on an explicit- inductive grammar learning task. Our results indicate that both WMC and inductive reasoning ability predict learning over three days of grammar training.