Chemistry plays a big role in this phenomenon. When we face criticism, rejection or fear, when we feel marginalized or minimized, our bodies produce higher levels of cortisol, a hormone that shuts down the thinking center of our brains and activates conflict aversion and protection behaviors. We become more reactive and sensitive. We often perceive even greater judgment and negativity than actually exists. And these effects can last for 26 hours or more, imprinting the interaction on our memories and magnifying the impact it has on our future behavior. Cortisol functions like a sustained-release tablet – the more we ruminate about our fear, the longer the impact.
Positive comments and conversations produce a chemical reaction too. They spur the production of oxytocin, a feel-good hormone that elevates our ability to communicate, collaborate and trust others by activating networks in our prefrontal cortex. But oxytocin metabolizes more quickly than cortisol, so its effects are less dramatic and long-lasting.