| Abstrakt: |
The conduction of nerve impulses within the pineal system of the frog has been investigated. Uninterrupted transmission of nerve impulses was seen after electrical stimulation of the intracranial pineal tract and recording of action potentials from the extracranial portion of the pineal nerve. The conduction velocities were at 2-9 m/sec (medullated fibres of 3-8 μ diameter), 1-2 m/sec (intermediate group, 1-3 μ) and 0.2-0.9 m/sec (unmyelinated fibres, 0.2-0.8 μ). The highest speed of conduction was observed in R. catesbyana where the slowest fibres were conducting at velocities of the same range as the fastest nerve fibres in some specimens of R. temporaria and R. esculenta. It was concluded that the conduction of afferent impulses from the frontal organ to the posterior commissure of the midbrain is based mainly on unmedullated fibres. [ABSTRACT FROM AUTHOR] |
