Because individuals with autism have difficulty communicating socially and understanding the emotions and intentions of others, it has been hypothesized that they may have a dysfunction in their mirror neuron system. This hypothesis has received a tremendous amount of attention in both the popular and scientific literatures following a number of studies that reported weak mirror neuron system responses in individuals with autism. The issue of movement-selectivity, however, had not been addressed.
To further test this influential theory, the researchers asked individuals with autism and a control group to observe and execute different hand movements while being scanned with functional magnetic resonance imaging (fMRI). The fMRI measurements allowed the researchers to infer the strength of neural responses in mirror system areas of each group during movement observation and execution. Their results showed that mirror system areas of individuals with autism not only responded strongly during movement observation, but did so in a movement-selective manner such that different movements exhibited unique neural responses. The mirror system responses of individuals with autism were, therefore, equivalent to those commonly reported (and observed here) for controls.
These results, they conclude, argue strongly against the “dysfunctional mirror system hypothesis of autism” because they show that mirror system areas respond normally in individuals with autism. The authors, therefore, suggest that it may be more productive to re-focus autism research in more promising directions.