"The many faces of sorrow": An empirical exploration of the psychological plurality of sadness.

Sadness has typically been associated with failure, defeat and loss, but it has also been suggested that sadness facilitates positive and restructuring emotional changes. This suggests that sadness is a multi-faceted emotion. This supports the idea that there might in fact be different facets of sadness that can be distinguished psychologically and physiologically.

Gratitude facilitates behavioral mimicry.

Recent theorists argue that gratitude, besides encouraging social exchange, serves an important function of relationship building. However, there is a lack of research exploring the specific behaviors through which gratitude promotes relationship building. Given that behavioral mimicry serves important affiliative needs, we explored whether gratitude promotes behavioral mimicry.