Studies on the effects of external pacing of heart sug-
gest  that the organ, like the nervous system, possesses the pro-
perties of ``memory'' and adaptation patterns persist long  after
the  agent  that  induced those changes is removed. After the ef-
fects of stimulation have disappeared, response to  the  stimulus
applied  for  a  second  time  is  much  greater than the earlier
response. Motivated by such results, this paper further  explores
the  possibility of a ``cardiac memory''. In particular, we point
out that communication via gap junctions  in  cardiac  tissue  is
similar  to  synaptic  conductance  in  nervous tissue and demon-
strate, with the aid of a mathematical model,  that cardiac  tis-
sue  can  exhibit  memory-like behavior if gap-junctional conduc-
tances are allowed to adapt according to a  Hebbian-like  mechan-
ism.

electrical activity of the heart, cardiac  memory,  con-
nectionist modeling, oscillations, Hebbian learning.