Bipolar disorder (BD) is a frequent and lifelong recurrent mood disorder with
treatment-resistant depressive episodes. Importantly, depressive symptoms and cognitive
decline are major determinants of functionality and quality of life in this clinical
population. There is robust evidence that individuals with BD have neurocognitive deficits
(especially in memory and executive functioning domains) compared to the healthy population.
These deficits are present in all mood states and can greatly affect patients' functional
capacity, often more so than mood symptoms themselves. Many pharmacological treatments for BD
adversely affect cognition, and those that are beneficial can be difficult to use. There is
thus a pressing need to identify a safe, easy-to-use medication that can target both
cognitive deficits and depressive symptoms in BD. It is expected that Brexpiprazole
adjunctive treatment will be efficacious in treating BD type I depression by improving mood
symptoms, as well as cognitive capacity and global functioning, and that such changes will be
accompanied by concurrent alterations in associated brain structures.