Need information: perceptual set

[Ford Prefect]

In my psychology course at school, we've come to our big, externally assessed project, commonly known as the IP. I'm basically going to perform and experiment, write it up, and submit it. I have decided to work on perceptual set, in particular motivation. I'm currently in the process of finding prior research and such on the concept, and I was wondering if anyone could point me in the direction of anything related that they've found to be interesting.

Thanks in advance.