Related Experiment Video
Updated: Jun 22, 2026

Understanding the Effects of Non-Invasive Transauricular Vagus Nerve Stimulation on EEG and HRV
Published on: January 19, 2024
Measuring appetitive responding with the postauricular reflex
Arthur R Sandt1, Denise M Sloan, Kareem J Johnson
1Department of Psychology, Temple University, Philadephia, Pennsylvania, USA.
Abstract:
Recent research has provided evidence that the postauricular reflex (PAR) is potentiated while people view pleasant images relative to unpleasant and neutral images. The present study sought to extend these findings by investigating whether the PAR is more robustly modulated by the appetitive salience of the stimuli. Eyeblink startle and PAR responses of 51 participants were recorded while they viewed images that varied in valence and thematic content. Participants displayed significantly greater mean PAR magnitude during appetitive-related images (e.g., food, erotica, families) compared with non-appetitive-related pleasant images. These findings support the contention that the PAR is a useful tool for measuring appetitive responding in humans.

