Figure 6.

Effects of acoustic stress on gastrointestinal migrating motor complex (MMC) (A) and heart rate viability (B) in conscious dogs. Acoustic stress almost completely abolishes gastric MMC (body and antrum) without affecting intestinal MMC (duodenum). During acoustic stress loading, heart rate and sympathetic tone (low frequency component; LF) are increased, while parasympathetic tone (high frequency component; HF) is reduced. As a result, the ratio between sympathetic tone and parasympathetic tone (LF/HF) is increaed by acoustic stress. Adapted from Taniguchi et al.⁸³