In fact, modern scientific research suggests, unsurprisingly, that people who believe they are less biased are in fact more prone to make decisions tainted by such biases. Conversely, judges are public figures, and most are acutely aware that their decisions are subject to harsh criticism from appellate courts, not to mention the media and public as a whole; could judges therefore overcompensate for biases that they suspect to be subject to public scrutiny?
Judges also often do read through the existing record before trial or argument and already form a tentative idea of the decision. Therefore, before even the first witness is sworn in at trial, or the first sentence is formed at appellate argument, a judge is already influenced by the beliefs they have formed before the main show:
Paul: Might it be fair to say that sometimes before oral argument the bench has votes in mind or you may ask an attorney to rebut the presumption you or a colleague already has in mind?
(Judge) Stabile: Well, I wouldn’t use the word presumption. When we go to argument, yes, most judges, many times, have formed a tentative opinion in your case. We already read your briefs, looked at cases and reviewed select parts of the record. It would be unrealistic to assume the court does not have at least a tentative opinion of your case if your brief presents your case well. Now, there are some cases where we say we really need to sort this one out. Then there are others where it’s pretty clear where the case is going.
Interview With the Judge, Theodore C. Tanski, Inder Deep Paul, The Pennsylvania Lawyer, March/April 2016 ed.
Knowledge and experience of psychology and bias usually cannot push a loser case into winning territory, but it can tip a close case towards one's favor by presenting the facts and the law most favorably towards the judge's biases and helping a judge find the legal justification for the result both the lawyer and the judge desires. Alternatively, if a lawyer recognizes a negative bias towards their case even before trial, it very well may serve the client greatly to either seek a jury trial (the proportion of bench to jury trials perhaps also an indicator of judge quality, or at least an indicator of how well a judge is able to either, or both, address and hide biases), or even pursue a more extreme measure, such as seeking the removal of the judge from the case.