Stress and anxiety are normal body responses when facing imminent or perceived danger. They generate the activation required to cope with these dangers or threats and seek solutions. However, a problem occurs when they become too intense or disproportionate to the stimulus that precipitated them, too long lasting (once the danger or challenge is gone or due to an inability to cope), or too frequent. The warning and activation response that is triggered, which aims first and foremost to mobilize resources for survival, is incompatible with sleep. That is why, when these emotions are sustained over time, they end up generating psychophysiological problems, such as insomnia.