Primitive nervous systems: electrical activity in the nerve cords of the parasitic flatworm, Gyrocotyle fimbriata.

  title={Primitive nervous systems: electrical activity in the nerve cords of the parasitic flatworm, Gyrocotyle fimbriata.},
  author={Larry Keenan and Harold Koopowitz and Michael H. Solon},
  journal={The Journal of parasitology},
  volume={70 1},
A large compound potential (LCP) could be evoked in the longitudinal nerve cords of Gyrocotyle fimbriata. This potential was graded and showed decremental conduction. Decrement was more pronounced in the posterior direction and was exponential with distance, dropping to 50% of its initial value in less than 5 mm. Conduction velocities in the anterior to posterior direction were greater than the reverse direction (means = 37.3 cm sec-1 vs. means = 30.3 cm sec-1). Single suprathreshold stimuli… 
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