A stereotaxic headholder for visual neurophysiology.

A stereotaxic headholder is presented that offers the following advantages: 1. It is especially suitable for visual neurophysiology, because the eye and surrounding orbit are not affected by bars or clamps. 2. It is easy to handle, because the ear bars are mounted on movable slides above the main frame. 3. It is versatile and can be used without additional adapters for different species of animals.