8. Dr. Smith wants to examine whether a new
drug increases the maze running performance
of older rats. Just like aging humans, older rats
show signs of poorer memory for new things.
Dr. Smith teaches two groups of older rats to
find a piece of tasty rat chow in the maze. One
group of rats is given the new drug while they
are learning the maze. The second group is
not given the drug. One week after having
learned the maze he retests the rats and
records how long it takes them to find the rat
chow.