Combining action observation with motor imagery, in brief doing AOMI, meaning to imagine a motor action whilst observing it, is currently a highly researched topic to which we’ve contributed just recently.
David Wright did a study using TMS during AO, MI and AOMI of a basketball free throw, me being part of the collaborative team. Results showed highest excitability for AOMI, with excitability for AO and MI not different to that of the control group. The study was just published, see here.
Corticospinal excitability was facilitated significantly by combined action observation and motor imagery of the basketball free throw, in comparison to both the action observation and control conditions. In contrast, the independent use of either action observation or motor imagery did not facilitate corticospinal excitability compared to the control condition.
And for the discussion on mental representation structures as they might develop by way of AOMI:
By combining the two techniques, AOMI interventions may develop the mental representation of a skill by enhancing both the sequencing between basic action concepts and the associated sensory consequences, and this in turn may lead to improvements in motor skill performance and learning.