A psychiatrist says that a significant mental disorder was a contributing factor to the death of a 55-year-old woman.

Stephen Ball, 32, was arrested after his mum Susanne Galvin was badly injured at their shared flat on Pear Avenue in Bury on September 16 last year.

Mrs Galvin was taken to Salford Royal Hospital where she died two days later.

Home Office pathologist Dr Philip Lumb gave the cause of her death as “blunt force head injury".

When Ball was arrested that evening a pair of Asics trainers were seized, and examination of the patterns matched those on Ms Galvin’s face.

Last week, prosecutor Gordon Cole KC told Bolton Crown Court said this was “consistent with stamping” on her face or head.

Ball is on trial after admitting to manslaughter but denying murder.

Yesterday, Monday, psychiatrist Dr Nikhil Khisty said he thinks that at the time of Mrs Galvin’s death, Ball was suffering from a serious relapse of schizoaffective disorder.

Read more: Bury man accused of killing mother at Bolton Crown Court

Dr Khisty believed Ball had been suffering from schizoaffective disorder for a number of years as well as using psychoactive substances which was also aggravating his mental state.

Dr Khisty said he believes he does meet the criteria required for "diminished responsibility".

Ball came to the attention of mental health services in 2012, and the court heard this was said to be the likely onset of the schizoaffective disorder.

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Following Ball’s arrest for the death of Ms Galvin, he was remanded in custody, taken to HMP Forest Bank and transferred to Ashworth High Secure Hospital after being described as "unwell" and "aggressive" until being treated with anti-psychotic medication.

Dr Khisty believes Ball’s mental health worsened in the months and weeks prior to the offence.

In July and August last year, his behaviour was described as agitated and erratic.

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His dad had tried to get him help on a number of occasions but with no result, the court was told.

On the day of the incident, Ball was described as being “in a state of panic” and officers described him as “erratic".

He also claimed to not have any recollection of the incident when asked about it and Dr Khisty believes Ball was suffering a relapse of schizoaffective disorder at the time.

The trial before the Honorary Recorder for Bolton Judge Martin Walsh continues.