Mason spent three months at Lorient two years ago.
"I'm not going to lie - it was probably the worst experience of my life," Mason told the London Evening Standard. "To be in a foreign country on your own and not even playing football was tough.
"I've got a close family and some really tight friends and without them I would have really struggled, but I spoke to them every day and that helped. The club put me up in an apartment about 10 minutes from the training ground. I'd finish training at 1pm every day and I'd have nothing to do.
"It was boring, it wasn't enjoyable and it made me eager to play football with a smile on my face. I don't ever want to be in that situation again. But I am strong in my mind, and coming through things like that means I appreciate playing for Tottenham a hell of a lot more than maybe others who haven't been through it."