On the development of eye-head coordination in freely moving rabbits during the first month of life.

Eye and head movements were recorded in unrestrained spontaneously behaving alert rabbits during the first postnatal month with the search coil technique using phase angle detection in a rotating magnetic field. In the first postnatal week saccadic eye movements occurred seldom and were of small amplitude. After an increase in frequency, amplitude, and velocity of saccadic eye movements the rabbits achieved an effective intersaccadic stabilization of eye position in space during active movements at the end of the third postnatal week. However, the characteristic adult pattern of alternate saccadic eye movements accompanied by head movements and slow eye movements compensating head movements was already observed at the time of eye opening (around the 12th postnatal day). Saccades initiated while the head was stationary occurred for the first time during the second postnatal week. It is concluded that the coordination and the dynamics of active eye and head movements in postnatally developing rabbits already considerably contribute to the reduction of retinal image slip velocity at the time of the postnatal opening of the eyes.