While it is well established that sensory cortical regions traditionally thought to be unimodal can be
activated by stimuli from modalities other than the dominant one, functions of such foreign-modal
activations are still not clear. Here we show that visual activations in early auditory cortex can be
related to whether or not the monkeys engaged in audio-visual tasks, to the time when the monkeys
reacted to the visual component of such tasks, and to the correctness of the monkeys’ response to the
auditory component of such tasks. These relationships between visual activations and behavior
suggest that auditory cortex can be recruited for visually-guided behavior and that visual activations
can prime auditory cortex such that it is prepared for processing future sounds. Our study thus
provides evidence that foreign-modal activations in sensory cortex can contribute to a subject’s ability
to perform tasks on stimuli from foreign and dominant modalities.