Geoffrey Melvill Jones has done work notable for its conceptual clarity, soundness and originality, on the physiology of the vestibular system, the control of movement, and the adaptive plasticity of the vestibulo–ocular reflex.

The evidence for plasticity is based on experiments with humans and animals which show that large adaptive changes can be induced in the vestibulo–ocular reflex arc by systematic alterations of the relationship between visual and vestibular responses to movement. He has analysed these changes quantitatively, and this remarkable discovery is now being energetically investigated in many other laboratories as well as his own.

He has done much work on the semicircular canals, including an intriguing allometric analysis of the results of measurements of their size in a wide range of species. Recently, he has embarked on a study of the ways in which the human bipedal locomotor system controls trajectory direction. He has also made valuable contributions to the solution of important practical problems in aerospace medicine such as spatial disorientation and long-duration flying stress .