Vagus Nerve Stimulation May Enhance Language Learning, DoD Study Reports

Transcutaneous cervical vagus nerve stimulation (tcVNS) may have applications in accelerating second-language acquisition, according to results of a study published in Scientific Reports. The data demonstrate that tcVNS stimulation using the gammaCore (electroCore, Rockaway, NJ) device enhanced second-language vocabulary acquisition while reducing fatigue and improving focus for linguist participants. This study was conducted by the US Department of Defense’s (DoD’s) Defense Language Institute (DLI) with support from the Defense Advanced Research Projects Agency (DARPA) and the Air Force Research Laboratory (AFRL).

The study included 36 participants who were participating in a 5-day Arabic language learning curriculum at the DLI. On day 1, participants were assessed for mood and baseline knowledge of a list of Arabic vocabulary words prior to administration of tcVNS. On days 2 through 4, participants were randomly assigned to self-administer either sham stimulation or active tcVNS using the gammaCore device before and after an Arabic vocabulary learning session; participants subsequently completed vocabulary recall and recognition tests to assess language acquisition. On day 5, participants received language instruction and completed the recall and recognition assessments without the use of stimulation to assess carry-over effects.

People who received tcVNS performed better in the 5-day DLI course:

• Active tcVNS was associated with better overall performance on Arabic vocabulary recall assessments compared with sham stimulation (P=.025).
• The improvement demonstrated on days 2 through 4 was maintained on day 5, indicating that the recall advantage continued after the discontinuation of tcVNS.
• According to results obtained from mood questionnaires completed by the participants each day, receipt of active stimulation was associated with a significant shift from fatigued to energized mood compared with those who received sham stimulation.
• Participants who received active stimulation scored higher energy (.036) and focus (.001) scores on the mood questionnaire each day compared with those who received sham.

“We are pleased to have successfully published the first randomized, double-blind sham-controlled trial demonstrating the ability of nVNS to accelerate the learning of Arabic vocabulary in students at the Defense Language Institute,” said Study Author Richard McKinley, PhD of the Air Force’s 711th Human Performance Wing and the Human Effectiveness Directorate. “Equally impressive were the improvements in the subject’s energy and mood despite the rigors of the training program.”