The subject in the study was a dead salmon. Researchers placed the fish in a brain imaging device. Next, they showed it pictures of a human in various social situations. They then asked the salmon what emotion the human must have felt. The researchers in turn discovered that the salmon's brain showed neural activity when confronted with the pictures.
This is a funny study that demonstrates that even when you have the best tool, if you don't know how to use it properly, you're going to get meaningless results. Click the link below to read the study. On the same page you will find a link to the audio if you would prefer to listen to it.