Dunleavy was today jailed for for nine years for burying her dismembered body in a shallow grave.
He killed his 66-year-old mum following a row at his flat in Edinburgh in spring 2013.
The thug, 41, who originally came from Dublin, was convicted of culpable homicide due to diminished at Edinburgh High Court in January 2014.
A jury heard how Dunleavy beat and strangled Philomena before cutting off her head and legs. Her remains were found on a clearing on Corstorphine Hill by a horrified cyclist
Judge Lord Jones sent the labourer to the state hospital in Carstairs, Lanarkshire, in order for his mental health to be assessed by psychiatrists.
On Wednesday, the judge ordered that Dunleavy serve his time in a conventional prison.
He made his decision after hearing evidence that Dunleavy was a psychopath who cut his mother open because he suspected she was a “reptile”. He wanted to look inside her to see if she was impersonating a human.
From their time with Dunleavy, medics concluded that Dunleavy was suitable for life in a normal jail.
Passing sentence, Lord Jones also ordered him to be supervised by the authorities for nine years following his release from prison.
He added: “I will impose an extended sentence of 18 years. The custodial element will be nine years.”
Mrs Dunleavy, from Marino, Dublin, had been visiting her son in the days leading up to the fatal attack. He had been working on the Edinburgh trams project.
Her remains were discovered in early June 2013 by ski ing instructor Aaron McLean-Foreman who was cycling on the hill.
Police launched Operation Sandpiper and appealed for help to identify the dismembered body.
They eventually identified Philomena’s body and arrested Dunleavy in July 2013.
At his trial, three psychiatrists told the court that Dunleavy had mental health problems but they needed time to assess him.
A jury acquitted Dunleavy of murder but convicted him on the lesser charge of culpable homicide due to diminished responsibility.
He was sent to Carstairs for his mental health to be assessed.
On Wednesday, consultant psychiatrist Khuram Khan told the court that he had assessed Dunleavy and believed him to be suffering from paranoid schizophrenia.
He told the court that Dunleavy had been responding positively to medication.
But the court heard that Dunleavy had been responsible for a number of anti-social incidents during his time in the state hospital.
He added: “He is engaging positively with the treatment. He has stopped engaging in anti-social behaviour.”
Talking about the examples of anti-social behaviour that the killer has engaged in, Dr Khan added: “Mr Dunleavy attacked another patient in the state hospital who he believed was trying to harm him and ridicule him. He has been experiencing suicidal thoughts.”
Mr Khan also told the court that Dunleavy told medics that he killed his mother because he thought she wasn’t human.
He added: “He believed his mother was a reptile and the only way to check was to look inside her body.”
Dr Khan believed that Dunleavy’s condition could be treated with medication and supervision from the authorities.
Dr Isabelle Campbell, a consultant forensic psychiatrist, told the court that Dunleavy had scored exceptionally high in tests to establish whether he was a psychopath.
The 59-year-old medical health professional said: “He has a psychopathy scale of over 30. It is extremely rare for patients in Carstairs or the general prison population to have a score that high.”
Dr Campbell told the court that she believed Dunleavy could not be treated for being a psychopath.
She added: “It is my professional opinion that psychopathy is not amenable to treatment.”
Consultant psychiatrist Gordon Skilling, 37, told the court that he believed Dunleavy posed a “continuing” and “high” risk to people who came into contact with him.
Dr Skilling told the court that he didn’t believe that Dunleavy suffered from paranoid schizophrenia.
He added: “He is better suited for the criminal justice system and not the hospital system.”
After hearing evidence, Lord Jones ruled that Dunleavy should be sent to prison and be supervised by the authorities following his release from jail.
On leaving court, Dunleavy’s father, Seamus told reporters that he was glad his son was being sent to prison.
But he said that he was convinced that his son wasn’t responsible for ending his late wife’s life.
He added: “He’s innocent.”