An EEG study to investigate the human mirror neuron system and its relationship to social abilities in healthy ageing.

The human mirror neuron system may play an important role in social abilities, such as our ability to empathise and understand other people. The functioning of the human neuron system in healthy ageing and its relationship to social abilities has not been previously investigated. We therefore examined age-related differences in sensorimotor mu desynchronisation as an EEG marker of the human mirror neuron system across the pre-motor cortex, motor cortex and supplementary motor area during action observation. Participants aged 18 to 86-years-old completed a hand movement observation task during EEG recording. Firstly, participants completed a 2-minute resting-state EEG as a reference period and, secondly, watched different video clips that depicted either a static hand or various hand actions, such as locking a door or clicking fingers. Participants also completed the Autism Quotient and Empathy Quotient as self-report measures of social abilities. For younger adults, we replicated previous findings of greater alpha and low beta desynchronisation during hand movement observation compared to static hand observation. We also found greater sensorimotor mu desynchronisation with increasing age. In addition, we examined how sensorimotor mu desynchronisation was related to general social abilities, including autistic traits and empathy ability. Therefore, this study reports the functioning of the human mirror neuron system across adulthood and how it may be related to social abilities.