Paroxysmal alien limb phenomena due to epileptic seizures and electrical cortical stimulation.

Alien limb phenomena (ALPs) are characterized by limb movements, which are subjectively experienced as involuntary or alien induced. ALPs regularly remain unchanged and occur as a consequence of frontal, callosal, or posterior cerebral lesions. The authors present two patients with paroxysmal ALP proved to be focal seizures by using video-EEG monitoring. In another two patients, ALP could experimentally be induced by electrical cortical stimulation. Based on the stimulation results, the authors suspect a functional disconnection of 1) sensory cortical areas providing information about the extrapersonal space; and 2) areas of the frontal and/or limbic cortex that are regularly involved in the processing and executing of intentional motor activity as a pathophysiologic substrate for ictal ALP.