The Mirror System (MS) may facilitate emotional processing, including the experience of empathy. We explored MS involvement in emotional processing using a novel affective startle paradigm and examined whether results were associated with empathy levels in a group of healthy participants.

Participants (n=69) viewed pictures that were divided into emotionally positive, neutral and negative categories. Pictures were preceded by emotionally congruent primes: half the primes consisted of a videoclip showing hand-object interaction designed to recruit the MS and half consisted of a control sequence showing static images of the interaction. Acoustic startle probes were presented during picture viewing and startle eyeblink responses were recorded. Participants were divided into high and low empathy groups based on their responses for the empathy subscale of the I7 questionnaire.

Startle amplitude was inhibited during positive picture viewing and potentiated during negative picture viewing when pictures were primed with moving videoclips compared to static controls. The biggest difference between amplitude associated with moving and static primes was found in the positive condition (p=0.009). The high empathy group exhibited a greater difference in startle amplitude between the moving and static conditions than the low empathy group for positive pictures (p=0.04).

Our results suggest that the MS modulates emotional processing, as reflected by enhanced startle reactivity when pictures were primed with moving videoclips designed to recruit the MS. This effect was more marked in the high empathy group, suggesting that high empathisers may be more sensitive to MS involvement in emotional processing.