Electric Fish Study
                 Investigations have been in progress on the species of electric fish,
              Sternarchus albifrons, and S. leptorhynchus, for 7 months.  Now, having
              sufficient equipwent, and with techniques developed over some months, we see
              good prospects for success in several lines of investigation.
                 Our initial work'was directed at the respon2ses of these fish to magnetic
              fields. Investigators using other species of electric fish have observed  strong,
              overt responses to extremely weak magnetic fields. It seems likely that  such  fistp,
              jith proven ability to perceive extremely weak electric fields, must be  responsivc
              to current induced in them by changing magnetic fields. However, our  investigatJ.ODS
              indicate that for Sternarchus at least, ther2e is no response to strong  (100  gauss),
              steady fields. Investigations with progressively weaker fields  continues  in  effoxt
              to eliminate the possibility of the blanking effect of too powerful stimulus.  Ttic
              case with the magnet may well be analagous to that reported for applied current
              on these fish: the smaller the applied stimulus; the greater the  relative  response.
                 A concurrent study will proc2eed using a  pulsed  magnetic  field,  Sternarchus  is
              Teported to respond to applied A.C. currents and fields far more readily than  to
              stimulation by currents and fields of D.C.
                  Also in progress is a study of threshold perception for A.C.  and  D.C.  current.
              There are several reports in the literature already on this topic.  However,  the
              data is reported in such a way as to render the work of question2au e usefulness to us.
              The threshold values are reported in Volts/distance.  Data on resistance of the syster
              must be obtained before such figures are useful.
                  The abo-@e experiments have a possible practical.application in  that  electric
              fish may find use as or as a model for energy detection in the  water.  The  electric
              field navigation system may also be practical and furt.ier baseline studies of  its2
              natural originators, the-elect@ric fish, will be invaluable.
                  The electrlc field of the electric fish is easily monitored by means of an
              amplifier and oscilloscope. As such, the fish provides what amounts to  a  living
              nerve preparation.  We feel that monitoring the free swimming animal provides a
              I'window" on nervous activity. As such, this animal could provide a useful  model
              for drug study. 3With the current,emphasis on the breakthrough  in  the  treatment  of
              Parkinson's disease with dopamine, we saw an opportunity to test this theory.
              Investigations are preliminary, but electrical activity and  physical  behavior  have
              been observed to be altered after several hours in, L-ROPA solution.