Maria has had a week of extreme "ups and downs." On Monday, after a wonderful weekend of homecoming events, she noticed herself feeling a bit blue and saddened. At first, she suspected it was just the letdown after all of the activities; however, her mood darkened until Friday when she found herself "over the moon" for no apparent reason. She was happy, care-free, full of energy, and exceedingly optimistic about her career. She even managed to whip out a 25-page research paper for her Research Methods class before nightfall. She loved these periods of boundless energy as they allowed her to accomplish much work with little need for sleep or eating. Given this overview of Maria's behavior during the week, what might be a clinical descriptor for it?