Suspense is constantly used throughout momento and is used to keep us the audience on the edge of our seats which is accomplished very well by Christopher Nolan. The movie starts with a strange but somehow engaging scene where the protaganist is shaking a photo and it is returning to a blank state, the orchestra music used here helps the suspense to build at a slow steady pace. The use of this creates a huge amount of suspense, aswell as the concious talking and black and white effect used.
The use of the bomb theory later in the film also creates huge suspense as we waait for the characters to realise what we know. Once the audience recognise something the character doesn't it leads to a constant build in suspense. There is alot of sounds used to build suspense in the scene, heavy breathing and a heart beat sound are the main suspense building sounds.
Also the audience are lured into a false plateau and this is a huge reason for the rise in suspense. The audience believe something is going to happen but as the film comes to a twist of an end we realise the truth about the characters. This is a good tool as the audience are constantly waiting for something to happen but it never does this is very suspense building as every close encounter will up the suspense a bit more.