Anders Behring Breivik, on trial for killing 77 people in Norway last year, stunned the Oslo courtroom on Wednesday when he drew a parallel between his own "trauma" and that he inflicted on the victims' families.

After hearing two psychologists describe the devastating effects the 22 July twin attacks have had on survivors and families of the victims, Breivik said it was "a shame they didn't talk about the trauma of seeing your ethnic culture and religion being taken away and not being able to do anything about it".

"It's traumatising to see your sisters raped by Muslims and your brothers beaten up," he said after he was given permission to address the court.

"This matter concerns the future of Norway and Europe. It's traumatising to be labelled a rightwing extremist" and to be "demonised", he said, ignoring the objections of chief judge Wenche Elizabeth Arntzen.

Breivik's comments prompted murmurs in the courtroom, where families of the victims were seated, some of whom chose to leave.

Earlier on Wednesday, after several days of testimony focusing on psychiatric questions, two witnesses described to the court the pain they still feel 11 months after losing loved ones in Breivik's bombing of government offices in Oslo and his shooting rampage on Utoeya island.

"It's like each of us has been broken and the family has also been torn apart," said Kirsten Vesterhus, who lost her 21-year-old son Haavard on Utoeya.

Fighting back tears, Tor Oestboe, whose wife Tove Knusten was killed in the Oslo bombing, said meanwhile he could not help wishing the "killer would burn slowly in Hell".

Breivik sat emotionless throughout their testimony, as he has throughout the trial, as sobbing was heard in the courtroom.

The trial has largely focused on determining whether or not he is criminally sane, as psychiatric evaluations of the 33-year-old rightwing extremist have sharply contradicted each other.

Breivik himself wants to be found sane — even though he would face a long prison sentence — in order to ensure that his Islamophobic ideology is not written off as the ravings of a lunatic.

If he is found insane he will be sent to a psychiatric ward.

Prosecutors are to present their closing arguments on Thursday, to be followed by those of the defence on Friday.

The verdict is expected on either 20 July or 24 August.