The role of ectopic grey matter in neuronal migration disorders is still a matter of debate. Using fMRI we studied the activation pattern of ectopic and regular cortical neurons in a female patient with subcortical bilateral laminar heterotopia (double cortex syndrome) performing a simple motor task. We demonstrate a synchronous activation pattern of the motor cortex and the adjacent subcortical ectopic grey matter layer during finger-tapping. We also observed activation in the cerebellum ipsilaterally and in the basal ganglia contralaterally. The present findings are consistent with the hypothesis that ectopic neurons may be functionally integrated in motor circuits during repetitive voluntary movements.