Strabismus disrupts binocular convergence in cat nucleus of the optic tract

Rendering kittens strabismic by surgical section of the medial rectus muscles results in disruption of binocular convergence in the nucleus of the optic tract. Visual input through the ipsilateral eye of strabismic cats does not influence cells in this nucleus although nearly one half of the cells encountered in normal cats receive inputs from both eyes. The results provide a basis for the deficits in optokinetic nystagmus found in strabismic cats and suggest a new mechanism underlying competition between inputs from the two eyes during postnatal development.