The organ most closely associated with sadness is the brain. It is the center of our emotions, and sadness is one of them. The brain processes signals from the environment, as well as from our own thoughts and memories, to create feelings of sadness. A number of neurotransmitters, such as serotonin and dopamine, are involved in the pathways that lead to sadness. Certain areas of the brain, such as the amygdala, hippocampus, and prefrontal cortex, are known to be involved in the processing of sadness. Additionally, certain hormones, such as cortisol, can influence the way we process and experience sadness.