Facial activity will be recorded with bipolar MRI-compatible electrodes attached over the zygomaticus major (involved in happy facial expressions) and corrugator supercilii (involved in fearful and anger expressions). EMG signal will be recorded at a sampling rate of 1024 Hz and band-pass filtered (20-500 Hz). Comparison between different stimulus conditions will be computed for mean peak of activities as well as at each time point to reveal the amplitude and temporal profile of the EMG response.4. Innovative research tools. In addition to the state-of-the-art but already established methodologies described above, we will use two emerging research tools that are particularly adept to investigate social interactions.