A mood swing is an extreme or sudden change of mood. Such changes can play a positive or a disruptive part in promoting problem solving and in producing flexible forward planning. When mood swings are severe, they may be categorized as part of a mental illness, such as bipolar disorder, where erratic and disruptive mood swings are a defining feature.
To determine mental health problems, people usually use charting with papers, interviews, or smartphone to track their mood/affect/emotion. Furthermore, mood swings do not just fluctuate between mania and depression, but in some conditions, involve anxiety.
