Imitation behavior is sensitive to visual perspective of the model: an fMRI study.

Imitation behavior and accompanying brain activity can be affected by the perspective of the model adopted. The present study was designed to understand the effect of a model's perspective in terms of the view (1st person vs. 3rd person) and the anatomical congruency of the limb between the model and the performer (congruent vs. incongruent). Eighteen young participants observed video clips of a model's finger-lifting behavior and lifted the same finger on their right hand as quickly as possible. Half of the video clips were filmed from the view of the participant (the 1st person view), whereas the other half were filmed from the perspective of facing a mirror (the 3rd person view). Each video clip depicted the finger lifting of the model's right (congruent) or left (incongruent) hand. Comparisons of the latency to imitate among the four perspective conditions showed significantly shorter latency for the 1st person-congruent and 3rd person-incongruent conditions. Hemodynamic measurements with functional magnetic resonance imaging showed that shorter latency was explained with less involvement of the brain areas that are activated when a task is relatively complex. The brain areas considered to be a part of neural substrates of imitation were significantly activated under the 1st person view conditions regardless of the hand congruency. These findings suggest that, although the latency to imitate finger lifting was determined by the complexity of the task induced with the model's perspective, imitation behavior seemed to be more effectively guided with the models filmed from the 1st person view.