Akinetic mutism is a medical term describing patients who tend neither to speak (mutism) nor move (akinesia). It is the result of severe frontal lobe injury in which the pattern of inhibitory control is one of increasing passivity and gradually decreasing speech and motion.
An example of a cause of this disorder would be an olfactory groove meningioma. It is also seen in the final stages of Creutzfeldt-Jakob Disease (a rare degenerative brain disease), and in acute cases of encephalitis lethargica. It can also occur in a stroke that affects both anterior cerebral artery territories. Another cause is neurotoxicity due to drugs such as Tacrolimus and Cyclosporine.
Another cause of both akinesia and mutism is ablation of the cingulate gyrus. Destruction of the cingulate gyrus has been used in the treatment of psychosis. Such lesions result in akinesia, mutism, apathy, and indifference to painful stimuli.[1]