XIX Physiological, behavioral and anatomical correlates of the development of hearing in the mouse

1. The initial Preyer reflex was observed in the mouse 9 to 14 days after birth with a mode of 12 days. 2. The onset of the cochlear potential was observed on the average of 11.6 days after birth. 3. The onset of the N₁N₂ was observed on the average of 12.5 days after birth. 4. The onset of the Preyer reflex was found to be associated with both the initial cochlear potential and the N₁N₂. 5. The N₁N₂ of the immature mouse had a greater latency and smaller amplitude than that of the mature mouse. 6. There were no gross differences found in the organ of Corti in those animals with and without a Preyer reflex. 7. There were no differences found in the organ of Corti in those animals who had or did not have the cochlear potential and an N₁N₂.