The ability of visual and muscle-proprioceptive information to elicit simultaneous sensory illusions and motor responses has been utilized to study some interactions between these two types of kinesthetic information. The effects of double stimulation (visual and muscular) have been analyzed in terms of the sensations and EMG activities induced and compared to the effects of the same stimuli employed singly. The parameters manipulated concerned chiefly the conflicting or non-conflicting character of the double stimulations as well as their organization in time. The results obtained demonstrate an absence of dominance of one or the other of the two kinesthetic inputs as well as a diversity of types of interaction.