Are you scared? I hope so. Apparently that will help you grasp the broad details of Mad Science Monday #3!
Mad Observations: Studies had shown that emotion (particularly fear) makes people see better, but the details of this sensitization were not investigated.
Mad Reference: "Emotion Improves and Impairs Early Vision." Bocanegra and Zeelenberg. Psychological Science Volume 20 Issue 6, Pages 707-713 (5 May 2009).
Mad Hypothesis: The emotional benefit to vision is limited in scope; some things will be easier to make out while in a state of enhanced emotion, other things will be harder to make out.
Mad Experiment: I had high hopes going into this one that the experiment might be truly mad, but it wasn't nearly as bad as it might have been. The researchers briefly showed people pictures of "fearful" faces and "neutral" faces, and then showed those people other images for the people to evaluate. This methodology relies on our mirror neurons causing us to feel a little bit of the fear we observe being experienced by a fellow human, without requiring that the test subjects actually get scared themselves. Again, I'm very disappointed; this was so close to really being mad.
They all laughed, but: The researchers found that the "scared" group had higher sensitivity to the orientation of "low-spatial-frequency stimuli" (ie, figuring out whether thick stripes were vertical or slightly tilted), but lower sensitivity to the orientation of "high-spatial-frequency stimuli" (figuring out whether thin stripes were vertical or slightly tilted).
The team's interpretation for this makes sense. When we're scared, we can notice details about coarse-grained features (things like movement of large objects), but noticing the exact texture of those large objects, for example, or the color of their eyes... that's less important.
Mad Engineering Applications: I could see a mad engineer using this to create some sort of invisibility-to-people-who-are-afraid device, although it'd probably only "work" in a TV movie vaguely referencing this research.
If you have any other ideas for mad engineering applications, let me know in the comments.