"My emotions have changed. Somehow I can't help that," he said.

"Being a Jungian psychologist, I would describe myself as less intuitive.

"More of a thinking, more rational, less intuitive person.

"Less sure if I can do things by inspiration."

Houghton, 68, is an experienced grief counsellor -- a major reason why he was selected for a clinical trial in 2000 for a new artificial heart implant.

He became the first patient to have the Jarvik 2000 ventricular pump implanted permanently.

The surgery undoubtedly improved his physical health -- after recovery, his workload included writing books, travelling the world giving speeches, and taking part in a 91-mile charity walk.

But the contrast in his emotional interactions became starkly obvious to him.

He found himself struggling to cultivate a relationship with his grandsons due to a lack of emotional connection.

Poets and philosophers have posited the heart as the seat of emotion for centuries.

But Broughton's background as a psychologist makes him fall back on his professional expertise for an explanation.

"The procedure lands you in a position that no one has ever pioneered -- what it does to a person as a person.

"You're an invented person trying to cope with it, trying to deal with the emotional context of it."