You are seeing a 29-year-old male patient in a primary care setting who has presented with a depressed mood, a loss of pleasure in activities, weight loss, feelings of guilt and decreased concentration. Upon further questioning, the patient informs you that they have also experienced a persistently elevated mood including a reduced need for sleep, flights of ideas and excessive involvement in high risk activities. However, the patient has also been hearing voices and a lack of emotions when these mood symptoms are not present. What is the most likely diagnosis?