ACHE and bipolar disorder: Interestingly some authors described, as clinical variant of LOBD, a bipolar type VI disorder, which is characterized by mixed-labile mood symptoms and cognitive dysfunction associated with hyperthymic/cyclothymic/irritable temperament, family history of bipolar disorder, refractoriness to antidepressants, and acetylcholinesterase inhibitors but favourable response to mood stabilizers and/or atypical antipsychotics [4].