Defense witness testifies at Knox's Italy murder trial

A neurologist testifying Friday at the trial of an American student accused of killing her British roommate said stress could have caused the defendant to have false memories about the night of the killing, news reports said.

The expert was called by the defense team of Amanda Knox, who is on trial with her former boyfriend Raffaele Sollecito for the 2007 slaying of Meredith Kercher, 21. They deny wrongdoing.

In the days after the slaying, Knox gave authorities conflicting statements, at one point saying she was in the house the night Kercher was killed there.

Neurologist Carlo Caltagirone told the court in the city of Perugia that Knox was under stress after long police questioning, which might have led to her confusion, the ANSA and Apcom news agencies reported.

"To be questioned for long hours in a foreign country without fully realizing the situation one is in ... can lead to a lot of stress," Caltagirone said, according to ANSA.

Knox initially accused Diya "Patrick" Lumumba, a Congolese man who owns a pub in Perugia where she worked, of being the killer. As a result of her accusations, Lumumba was briefly jailed. He was later cleared and is seeking defamation damages from Knox.

Knox, 22, of Seattle, Washington, has since maintained that she spent the night of the murder at Sollecito's house.

In June, the American testified in court that she was beaten by police and was confused when she was questioned. She said it was the pressure that led her to accuse Lumumba.

Police have denied any misconduct.

The trial began in January.