Abstract idealized mental visualization improves motor task performance I practice martial arts (Aikido), which involves a lot of rotation.

When practicing, I find that holding an abstract image in my head, instead of thinking about the actual technique, improves my performance of the technique.

For example, when rotation is required, my mental image is essentially a vertical spiral pulled tight in the middle (as if constrained by a belt), in that one comes in to the axis of rotation and must stay on it before moving off into the rest of the technique.

The question, then is:
What explains why an abstract mental image can improve adherence to an ideal set of movements?  

And, can this be explained neuro-biologically and, if yes, how?

(I suspect that the two questions have similar, if not the same, answers - hence why I've included both instead of separating them)

If you prefer to not answer those questions, believe that I should be answering these myself, or believe that this is not high-enough quality for CogSci (I apologize for any improper terminology), please offer a direction in which I can start my research into this phenomena, as at the moment I am at a loss for where to begin.
I would hazard a guess that some type of motor system interference is taking place when you visualize the movement versus visualizing an abstract shape.

For example, Kilner et al. (2003) found that actions that are observed can interfere with incongruous executed actions.  They had subjects make arm movements that were either similar or dissimilar to those of another human or a robot.  Movements that were not similar caused a greater amount of error in the arm movement of the subject. Since motor visualization can recruit many of the same areas of cortex as actual observation and execution (Kosslyn et al., 2001), this could cause similar interference.

Other papers, such as Rémy et al. (2010), have shown that there is reduced motor learning when two movements were acquired at the same time.  Their hypothesis was that the two movements both recruited similar areas of cortex, which caused a form of competitive interference. Visualizing a movement before execution could generate competition between similar, but not identical, movement representations.

Finally, there is evidence that varied practice, or learning a motor movement in several different ways, can cause a short-term degradation of motor learning, but can cause long term increases in retention and generalization of a motor movement.  Magill and Hall (1990) had a nice review of this effect, called contextual interference.  Visualizing the movement could be causing reduced performance now, but it could be argued that it may be beneficial in the long-term.

Wikipedia has some surprisingly good articles on motor learning and task interference if you are interested in learning more:
Motor learning: http://en.wikipedia.org/wiki/Motor_learning
Interference theory: http://en.wikipedia.org/wiki/Interference_theory


 Kilner JM, Paulignan Y, Blakemore SJ. (2003) An interference effect of observed biological movement on action. Current biology, 13(6), 522–525.
Kosslyn SM, Ganis G, and Thomson WL. (2001) Neural foundations of imagery. Nature Reviews Neuroscience, 2, 635-642.
Magill RA and Hall KG (1990) A review of the contextual interference effect in motor skill acquisition. Human Movement Science, 9, 241-289.