How can a physician detect vagal stimulation on a depressed person?

A physician can detect vagal stimulation in a depressed person by observing physiological responses such as heart rate variability, which may indicate heightened vagal tone. They may also assess symptoms related to vagal responses, such as changes in gastrointestinal function or levels of anxiety. Additionally, monitoring responses to specific therapies, like deep breathing exercises or mindfulness techniques, can provide insights into vagal activity. However, definitive assessment often requires specialized tools like heart rate monitors or imaging techniques.