<qa>  What is the main challenge in the treatment of Bipolar Disorder?One of the main challenges in the treatment of Bipolar Disorder BD is to achieve better functioning outcomes after syndromal recovery. Even treatment-responsive patients, who remain symptomatically well for extended periods of time, frequently demonstrate sub-threshold symptoms and continuing psychosocial morbidity and cognitive impairment. The cognitive impairment that persists during interepisode periods stands out as a major correlate of functional impairment, and may be a core aspect of the BD pathophysiology. 