Binocular eye movements form a finely-tuned system that requires accurate coordination of the oculomotor dynamics
and supports the vergence movements for tracking the fine binocular disparities required for 3D vision, and are
particularly susceptible to disruption by brain injury and other neural dysfunctions. Saccadic dynamics for a population
of 84 diverse participants show tight coefficients of variation of 2-10% of the mean value of each parameter.
Significantly slower dynamics were seen for vertical upward saccades. Binocular coordination of saccades was accurate
to within 1-4%, implying the operation of brainstem coordination mechanisms rather than independent cortical control of
the two eyes. A new principle of oculomotor control - reciprocal binocular inhibition – is introduced to complement
Sherrington’s and Hering’s Laws. This new law accounts for the fact that symmetrical vergence responses are about five
times slower than saccades of the same amplitude, although a comprehensive analysis of asymmetrical vergence
responses revealed unexpected variety in vergence dynamics. This analysis of the variety of human vergence responses
thus contributes substantially to the understanding of the oculomotor control mechanisms underlying the generation of
vergence movements and of the deficits in the oculomotor control resulting from mild traumatic brain injury.