Statistical Language Learning and Vagus Nerve Stimulation: A Pilot Study

Abstract

Applying transcutaneous stimulation to the auricular branch of the vagus nerve (tVNS) has been shown to enhance associative learning in humans. The main goal of the project is to investigate the effect tVNS has on procedural learning, specifically implicit statistical language learning. The aim of the experiment reported in this paper was to determine which statistical language learning paradigms would be appropriate to use with tVNS. Since we would be looking at within-subject changes between two sessions (one session with, one session without stimulation), we tested the test-retest reliability of two statistical learning paradigms.  We also tested the correlation between a explicit phonological memory task and the implicit statistical learning tasks to determine whether phonological memory was involved in the statistical learning tasks. Our results showed a high test-retest reliability for the word segmentation and adjacent dependencies statistical learning task. However, the second statistical learning task dealing with non-adjacent dependencies had low test-retest reliability, meaning it would not be appropriate for future studies incorporating tVNS. There was a high correlation between the phonological memory task and both statistical learning taks, indicating implicit statistical learning may recruit phonological memory.