The influence of repeated rotations on decerebrate and on blinded squabs.

Abstract

The experiments were made on young pigeons which had never had the opportunity to fly. The head nystagmus occurring during rotation (rotation-nystagmus) and that which followed cessation of rotation (after-nystagmus) were recorded graphically. It was found that the rotation nystagmus decreased but slightly in 7 days'' practice; the reduction of the rotation nystagmus is practically alike in normal and in decerebrate birds; the after-nystagmus is markedly reduced in normal birds, and suffers much less reduction in decerebrate birds; repeated rotation of blinded birds causes a greater reduction of the rotation-nystagmus than in normal birds, but less reduction of the after-nystagmus than in the decerebrate birds. The experiments indicate that retinal stimuli have more influence on after-nystagmus than on rotation-nystagmus, and this influence comes into play in part at least through the functioning of the cerebral hemispheres.