Functioning of the Mirror Neuron System in Children with HFA during Observation and Imitation of a Precision Grip: An EEG Study

Background: During passive observation of actions performed by others, cortical brain regions that are also involved in the execution of actions, become activated. These regions form an observation/execution matching system, the so-called mirror neuron system, which contributes to action comprehension and imitation by translating visual input into motor understanding. Previous research has suggested that a dysfunction of this system may underlie the characteristics of autism, such as deficits in imitation, theory of mind, empathy and pragmatic language. In addition, studies have shown that the reduced power of the mu frequency EEG oscillations (8-13 Hz) during action performance and observation of human movement indicates MNS activity.
Objectives: To investigate the MNS activity in children with high-functioning autism (HFA) during imitation, execution, and observation of a goal/object-oriented movement.

Methods: Normally intelligent children (9 to 13 years) with HFA were compared with age-matched normally developing peers. The children were asked 1) to observe a picture of a manipulandum, 2) to observe a precision grip of a manipulandum, 3) to observe a simple hand movement, 4) to imitate a precision grip and 5) to self-initiate the previous seen precision grip. During these conditions, 128-channel EEG was recorded.
Results: Preliminary results indicate that mu suppression is comparable between the HFA and the control group in action-imitation/execution conditions, as well as in action-observation conditions. Further analyses are currently in progress.

Conclusions: These preliminary findings give no support to the hypothesis of an impaired MNS in school-aged children with HFA.