Why is someone else's bad mood more contagious than happiness? Don't let it infect you.

Some days begin with energy and motivation, but simply interacting with people who are stressed or in a bad mood can radically transform that positive state. Scientific evidence confirms that negative emotions are remarkably contagious.

According to the International Society of Substance Use Professionals (ISSP), emotional contagion is the ability of people to influence the emotions and behaviors of others, either directly or indirectly. The etymology of the word "contagion" in emotional contagion comes from the conscious and unconscious acts of sharing emotions with others through verbal or physical expression.

Although the word “contagion” may sound intimidating, emotional contagion can also be a powerful tool for social connection and learning. For example, the human brain adapts to an “emotional culture” that allows it to read the emotions of others and adjust its own responses to be socially appropriate. Neurologists have discovered that mirror neurons are responsible for this phenomenon and function as a very useful learning tool.

Some people are more sensitive to emotional contagion than others. Because this phenomenon can influence thoughts and feelings, it can cause mood swings. Furthermore, it has been observed that certain moods and personalities are more susceptible to being "contagious" than others.

Research such as that of Hatfield et al. (1994) and Goleman (1996) demonstrates that fear, anger, and sadness have a more intense effect than positive emotions. These activate brain areas such as the amygdala, which is responsible for processing threats, triggering an automatic state of alert. Prolonged exposure to complaining or hostile people increases cortisol levels and produces muscle tension, altering one's emotional balance.

While mirror neurons facilitate empathic connection and social cooperation, they also increase susceptibility to social stress. In negative environments—such as toxic offices or conflicting family dynamics—it's common to absorb the distress of others, even when one initially maintains a positive mood.

Given this situation, ISSP recommends practical strategies to protect against emotional contagion and maintain a healthy emotional balance:

- Be present: When a person finds themselves in a situation that creates emotional pressure from their peers, it's helpful to take a moment to reflect: "Is this really how I feel, or is it just how I think I should feel?" Giving yourself the opportunity to question whether the feelings you're experiencing are your own or someone else's helps you identify which emotions are authentic and which are influenced by others.

- Fake it till you make it : Everyone has bad days, but if your own or someone else's mood is polluting the air, smiling and laughing can be helpful exercises. Activating your facial muscles when you smile activates mirror neurons and facial memory, generating a feeling of happiness that, over time, could become contagious to others.

- Seek professional guidance: For those who are especially sensitive to the emotions of others, it is beneficial to evaluate their relationships and the emotional triggers they experience. Consulting with a trained professional can help them recognize thought patterns, develop healthy coping skills, and ultimately reduce emotional contagion in their lives.

In short, the influence of negative emotions is more powerful than we often imagine. However, emotional contagion, when well managed, can become a valuable tool for strengthening bonds and maintaining a healthy emotional balance.