Nages Nagaratnam, MD, FRCP, FRACP, FRCPA, FACC, Consultant Physician, Geriatric Medicine, formerly Blacktown-Mount Druitt Health, Blacktown, New South Wales, Australia.
Gowrie Pavan, MBBS, FRAGP, General Practitioner, The Surgery, Plympton Road, Beecroft, New South Wales, Australia.

Mutism in older adults is not uncommon. It is often confused with severe depression, locked-in syndrome, and persistent vegetative state, but it is important to distinguish among them as the management and prognosis are different. The family physician is the most consulted professional and so is the most helpful in making this distinction. Mutism is a neuropsychological disorder with marked heterogeneity among patients, raising the possibility of conditions such as advanced Alzheimer’s disease, Jacob-Creutzfeldt disease, frontotemporal dementias, and certain psychiatric and psychological conditions. It is both a symptom and a syndrome, and is often associated with akinesia when the term akinetic mutism is used. Akinetic mutism has a number of causes with varied pathology and is characterized by a marked reduction in motor function, including facial expression, gestures, and speech output, with awareness being preserved. All of the disease manifestations can be explained by damage to the frontal lobe or interruption of the complex frontal subcortical circuits and the frontal diencephalic brain stem system by focal lesions or diffuse brain damage.
Key words: mutism, akinetic mutism, frontal-subcortical circuitry, locked-in-syndrome, persistent vegetative state.