Myoclonic epilepsy is being increasingly recognized as a late-onset complication in middle-aged or elderly patients with Down syndrome, in association with cognitive decline. We show video and EEG recordings of two patients, both aged 56 years, diagnosed with this condition. At onset, myoclonic epilepsy in elderly DS patients may resemble, in its clinical expression, the classical juvenile myoclonic epilepsy with the characteristic occurrence of jerks on awakening. It is clearly associated with an Alzheimer-type dementia, and may also occur in non-DS patients with Alzheimer's disease: hence the possible denomination of "senile myoclonic epilepsy". [Published with video sequences].