They genetically modified some mice to lack a gene that codes for PKR formation, and subjected the mice to some memory tests. A spatial memory test required mice to use visual cues to find a hidden platform inside a circular pool, for instance. Regular mice had to repeat the task a few times over a few days to remember where the platform was located, but the PKR-deficient mice figured it out after just one training session, according to a Baylor news release. Dr. Mauro Costa-Mattioli, assistant professor of neuroscience at BCM and lead author on the paper, said the researchers found that another immune enzyme, gamma interferon, took over some of PKR's memory functions. It increased synaptic communication among neurons and gave the mice a sort of "super-memory," Costa-Mattioli said.