A storage apparatus includes memory devices each having a storage element
with a characteristic that the application of an electric signal not
lower than a first threshold signal allows the storage element to shift
from a high resistance value state to a low resistance value state, and
that the application of an electric signal not lower than a second
threshold signal, which has a polarity different from that of the first
threshold signal, allows the storage element to shift form a low
resistance value state to a high resistance value state, and a circuit
element connected to the storage element in series to be a load; wherein
the memory devices are arranged in a matrix and one terminal of each of
the memory devices is connected to a common line; and wherein an
intermediate potential between a power supply potential and a ground
potential is applied to the common line.