Watching object related movements modulates mirror-like activity in parietal brain regions

More proof of action observation. See how long before your doctor and therapists give you stroke protocols based upon this. 10-20 years I bet. No self-prescribing, you know how dangerous it is watching videos of muscle movement.
http://www.clinph-journal.com/article/S1388-2457%2813%2900120-X/abstract

Highlights 

•The observation of goal-directed movements leads to stronger event-related desynchronization (ERD) in alpha, beta and gamma frequency bands over parietal compared to central brain regions.

•Both the type of grasping and the type of object induced an ERS over sensorimotor areas in the upper alpha and lower beta band, respectively.

•Beside the often cited MNS linked mu rhythm there is further cortical rhythmicity over parietal sites, which might be part of an “extended” human MNS.

Abstract 

Objective

We studied the activation of cortical motor and parietal areas during the observation of object related grasping movements. By manipulating the type of an object (realistic versus abstract) and the type of grasping (correct versus incorrect), we addressed the question how observing such object related movements influences cortical rhythmicity, especially the mu-rhythm, in the context of an “extended” human mirror neuron system (MNS).

Methods

Multichannel electroencephalogram (EEG) was recorded during the observation of different object-related grasping actions in twenty healthy subjects. Different movies were presented, showing sequences of correct or incorrect hand grasping actions related to an abstract or realistic (daily life) object.

Results

Event-related de/synchronization (ERD/ERS) analyses revealed a larger ERD in the upper alpha (10–12Hz), beta (16–20Hz) and gamma (36–40Hz) frequency bands over parietal brain regions depending on the type of grasping. The type of object only influenced ERD patterns in the gamma band range (36–40Hz) at parietal sites suggesting a strong relation of gamma band activity and cortical object representation. Abstract and realistic objects produced lower beta band synchronization at central sites only, whereas depending on the type of grasping an ERS in the upper alpha band (10–12Hz) was observed.

Conclusion

Depending on the type of the grasped object and the type of grasping stronger parietal cortical activation occurred during movement observation.

Significance

Discussing the results in terms of an “extended” human mirror neuron system (MNS), it could be concluded that beside sensorimotor areas a stronger involvement of parietal brain regions was found depending on the type of object and grasping movement observed.