Breivik's sanity is the key issue in his 10-week trial. The subject was re-examined in Monday's nine-hour session, days before closing arguments on June 21-22. A verdict is expected in July or August.
The Oslo District Court will have to decide on Breivik's sanity after hearing an earlier contradictory report by other psychiatrists that found him to be psychotic.
The 33-year-old killer insists he is sane and has admitted to the killings. He denies criminal guilt, claiming his victims had betrayed their country by embracing immigration.