David Tarloff, a man with schizophrenia who bludgeoned and stabbed a psychologist to death during a botched robbery six years ago, was found guilty of her murder on Friday by a Manhattan jury that rejected an insanity defense.

The verdict in State Supreme Court came in the third attempt to convict him. A year ago, a mistrial was declared after the jury announced it was deadlocked. The first trial, in 2010, stalled during jury selection when Mr. Tarloff became unstable.

Mr. Tarloff, who appeared with long, scraggly hair in a dingy sweatsuit, betrayed little emotion as the jury forewoman rose to read the verdicts, reached after seven hours of deliberations.

The jury found him guilty of first-degree murder in the attack, with a meat cleaver and a rubber mallet, on the psychologist, Kathryn Faughey. He was also found guilty of assault and attempted robbery for maiming Dr. Kent D. Shinbach, a psychiatrist who shared an office with her.