This is slightly more advanced than changing your memories.
In the early 20th century, a man named Hermann Minkowski first proposed the concept
of a space-time continuum. Using his idea, everything creates a 'world line'.
Basically, it's like every instant, from the beginning of time on, is like a single frame of film. We start at one point on the film, and work are way up, until the point of our death.
Looking at it from a physcial point of view, it would look like this:
-----+-----
---+-------
------+----
---+-------
----+------
The "+'s" would be you, and the "-'s" would be the 'frames of film.' In this diagram, up and down is the time axis, and left and right is the space axis.
As you can see, if you were to 'connect the dots', you would form a line, that starts at your birth, and ends at your death. This is called a world line.
Your mind (consciousness) travels from frame to frame.
I think that when people have visions of the future, or deja'vu or the like, what has happend is that their minds skipped ahead to a future point of the film, like fast forwarding to the end of a movie.
I think this is because of the subconscious. After reading some psychology texts, I have learned that whereas the consciousness measures time in past and future, the Sub-c is timeless. Everytime, to the Sub, is now.
I think it is this ignorance of time that allows it to occationally slip up.
The device will augment this effect.