Abstract
1. The chief parameters of evoked potentials recorded in response to acoustic stimulation (clicks, tones) in the acoustic nuclei of the medulla (dorsal cochlear nucleus, olivary nucleus) inRana temporaria are described. 2. The maxima of frequency sensitivity of medullary evoked potentials lie in the region 0.4–1.4 kHz. The frequency curves exhibit variability and dependence on stimulus intensity. 3. Extirpation of the columella and tympanic membrane changes the frequency curve, and the amplitude of responses to clicks and tones falls. It may be assumed that columellar transmission of sound in frogs is not the only channel of sound conduction. 4. Recovery cycles obtained during the action of paired clicks have a mean duration of 30 msec for medullary potentials. 5. An increase in duration of the front of tonal stimuli from 0 to 3 msec leads to a sharp decrease in amplitude of the medullary responses. With a further increase in duration of the fronts, the response amplitude shows a smaller change. It is also dependent on stimulus frequency.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call