A lecture will explore how the Tudors and Stuarts believed the Devil was responsible for planting thoughts in people's minds.
Darren Oldridge, Professor of Early Modern History at the University of Worcester, will explore attitudes in that period and how our perspective has changed at an upcoming free public lecture.
"It was widely believed in Tudor and Stuart England that evil spirits could hijack human consciousness," said Professor Oldridge, who will speak at The Hive, on Wednesday, May 3.
"They could whisper dreadful temptations into a person's imagination or, worse, plant alien thoughts inside their mind."
The lecture, entitled Demons of the Mind: Madness and Temptation in Tudor and Stuart England, will explain how people then would not have viewed such experiences through the prism of our modern understanding of mental health.
Professor Oldridge said: "On the contrary, the Devil's "injections" were viewed in the sixteenth and seventeenth centuries as an expected but unpleasant aspect of Christian life."
Professor Oldridge says writing from the time shows the pastors of the Church of England offered guidance on how to identify these demonic thoughts " and what to do about them.
"Demonic thoughts were sudden, horrible and irresistible. But those who received them were not responsible, as long as they did not enjoy them or act on them," he added.
Famous sufferers, he says, included John Bunyan, the author of the classic Christian adventure, The Pilgrim's Progress.
Prof Oldridge's talk starts at 6 pm.