This is a single-site pilot study to assess the safety, feasibility, and potential therapeutic effect of paired-taVNS cognitive training in healthy individuals and people with PD. In the longitudinal study, healthy and PD participants will be prospectively assigned to receive either the sham or active intervention based on order of enrollment in the study. In the acute study, healthy participants will receive both the sham and active intervention, where the order will be prospectively randomized based on order of enrollment in the study.