Subjectivity of typical experiments used to investigate the existence of mirror neurons - biomed 2011

Biomed Sci Instrum. 2011:47:294-9.

Abstract

Typical experiments used in investigating the mirror neuron theory involve a person executing a task, and an animal (usually a rhesus or nemestrina macaque primate), instrumented or under observation in some other manner, that is supposed to imitate the task. To evaluate if in fact the animal imitates the person and not the opposite, we asked a group of 70 first year veterinary medicine students with no experience with these type of experiments to evaluate two publicly available movies of two such experiments and to answer a multiple-choice questionnaire. They were asked to judge if, in their opinion, the animal imitated the person or if it appeared that the person imitated or followed the animal. The order of the multiple choices was randomized to avoid biases. In one movie, the majority of the subjects found that the person seemed to follow the animal and not the opposite as it should have been. For the other movie, about 14% of the subjects also answered that the person followed the animal. This suggests there is a great deal of subjectivity in how these experiments are conducted and evaluated that might affect the conclusion of the investigations, raising doubts on their validity. We also raise some other questions about the validity of the experimental model in relation to other experiments used investigations about the hypothesized mirror neurons. This work is an invitation to caution with regards to proposing and accepting the mirror neuron theory based on the experiments conducted thus far.