In choosing to play the tournament, which starts on Thursday, the 42-year-old will miss the premiere of a film based on the life of his father, Milkha Singh, known as the Flying Sikh, who finished fourth in the 400 metres at the 1960 Rome Olympics.
However, Singh, who won in a playoff against Italy's Francesco Molinari last year, said he had arrived in Scotland with his father's blessing.
"We did discuss it and being a sportsman himself, he wanted me to defend this championship," Singh told the European Tour website.
"The director did a show for the family before I flew out. I've seen the movie and I think it's a fantastic movie," he added.
Singh will need to shake off a finger injury and some indifferent form, having missed the cut in his last four starts, if he is to overcome a field that also includes world number eight Phil Mickelson and number 13 Ernie Els.
"The right index finger is not 100 per cent, and I just feel that I'm going to stop thinking about it now," Singh said. "It just hurts when I hit shots, but I've got to go with the flow."
Four-times major winner Mickelson is using the Scottish event as a warm-up for next week's Open Championship at Muirfield, a tournament he has never won.
"I think it would be one of my greatest accomplishments to be able to conquer links golf and to win an Open championship over here," said Mickelson. "Although I've come close maybe twice, I have not really played my best golf."
The left-hander is also keen to shake off the disappointment of his final round at last month's US Open when he started with a one-shot lead but ended up tied fourth, two strokes behind winner Justin Rose.
"I don't want to diminish it, because it takes a while, and it hurt," said Mickelson.
"But part of professional golf is dealing with losing and dealing with disappointment and being resilient and using it as a stepping stone.
"And so rather than look at it as a failure, I want to use it as an opportunity to take advantage of where my game has got in these last few months and try to have a great second half of the year, starting here in the Scottish Open and the Open as well as the US PGA Championship and our FedEx Cup back in the US."
South African Els will also have one eye on the Open when he tees off at Castle Stuart for what he hopes will be the perfect preparation for the defence of his title.
"I was not going to play, but I always had in the back of my mind that it is tough to go into a major with a three-week break, said Els who twice won the Scottish Open when it was held at Loch Lomond.
"I think I might have done it in the past but I feel a little awkward doing that.
"Obviously playing an Open the week after the Scottish Open is perfect preparation to play some kind of links form," he added.