Dr Christine Gill has challenged her parents' will
Today Rob Howard, a consultant psychiatrist, told the resumed hearing he had compiled a report about Mrs Gill's mental health based on witness statements and came to the conclusion she suffered from agoraphobia with panic disorder, which began in her childhood.
Professor Howard told the court he believed Mrs Gill would have been very anxious when faced with meeting a solicitor and would not have been able to take much in.
In his statement, he said: 'Seeing a solicitor, even with Mr Gill being present, would have been outside the set of situations within which Mrs Gill would have been expected to have been able to prevent the emergence of severe anxiety symptoms.
'My opinion would be that this would be likely to have materially affected her ability to concentrate upon and digest what was being said to her during such a meeting.'
Professor Howard agreed with Claire Royston, a consultant psychiatrist giving evidence for the RSPCA, that it was likely Mrs Gill would have conformed with the wishes of her husband when they made their wills in 1993.
The court heard previously that Mr Gill was stubborn and domineering towards his wife, who went everywhere with her husband and was dependent on him to make decisions for her.
Professor Howard's statement continued: 'Her dependence upon Mr Gill would have made it very difficult for her to express a wish to make a will that was different from one that he wished to make.'
But the two medical experts disagreed about Mrs Gill's mental state.
In a joint statement, Professor Howard and Dr Royston said: 'Dr Royston does not believe that Mrs Gill would have met criteria for any formal psychiatric disorder but should most usefully be viewed as having been an eccentric woman.'
The court has heard that Dr Gill - an only child - was given repeated assurances that she would inherit Potto Carr Farm, in North Yorkshire, when her parents died.
The university lecturer told the court she had devoted most of her spare time over a period of more than 30 years to voluntarily helping out at the farm.
When Mr Gill died in 1999, aged 82, she was left to look after her mother and run the farm, the court has heard.
It was only when her mother died in 2006, also aged 82, that Dr Gill saw the will, which left everything to the RSPCA.
The hearing is due to last until the end of the week.