What is required to raise a doubt in a mental health case?

discretionary, it is clear that 'more is required to raise a doubt than mere bizarre actions [citation] or bizarre statements [citation] or statements of defense counsel that defendant is incapable of cooperating in his defense [citation] or psychiatric testimony that defendant is immature, dangerous, psychopathic, or homicidal or such diagnosis with little reference to defendant's ability to assist in his own defense [citation].' [Citation.]" (People v. Welch (1999) 20 Cal.4th 701, 742.)