Ideomotor apraxia is a disorder affecting patients with stroke and a variety of other brain lesions. The disorder involves problematic timing, sequence, and spatial organization of gestured movements. As a result, patients suffer from incorrect temporal and spatial components to movements as evidenced during pantomime of transitive and intransitive movements. The errors can be seen in left and right hemisphere damaged patients during intransitive movements, but lesions predominate in the left hemisphere for inability to pantomime transitive movements. Thus far, damage to parietofrontal circuits has been implicated in significantly contributing to this disorder. These circuits, which pave the way for sensorimotor processing, are of clear interest in the nature of praxis.

In the present study, we plan to evaluate further the parietofrontal circuits in these patients. Using EEG, we will analyze the movement related cortical potentials (MRCP) in these patients compared to controls to evaluate any cortical planning differences. We will analyze how the circuits play a role in transitive and intransitive movements in normal subjects and patients with Ideomotor apraxia. Each patient will make a series of movement during 64 channel EEG and EMG recordings. Following recordings, analysis will be made of the event related desynchronization (ERD) and the MRCP. Further analysis will look at the activation of the parietofrontal circuitry in patients using correlation and coherence methods. For the same purposes, MEG studies will be performed to assess similar measures.