Is the shape below rotated to the right or the left?
How about this one?
The process by which our nervous system converts physical stimuli to neural activity is referred to as sensation, but making sense of that information is referred to as perception. The field of studying how physical differences in stimuli affect perception is called psychophysics, and one of the research techniques for studying this is signal detection theory. The ideas behind signal detection theory occur frequently in user research, so they’re worth reviewing here. Whether we’re trying to detect whether a product change influences user satisfaction, or trying to measure preference for a product design, having a good understanding of signal detection theory serves as a foundation for future research method discussions. Most importantly, the same scientific rigors used to measure perceptions can be used to measure preferences. After all, isn’t preference just a type of perception, as in, perceived benefit, or perceived value?